    [From the U.S. Government Printing Office, www.gpo.gov]

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                                                  CITY OF EUREKA                                                      2 -1 -
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                       CALIFORNIA COASTAL CONSERVANCY

                                          PALCO MARSH
                          ENHANCEMENT PLAN
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                    1884 MYRTLE AVENUE EUREKA, CA 98501 (7073 443-866                                            j/44s_E4a3

                                     PROJECT INFORMATION

              Project Name: Palco Marsh Wetland Enhancement Plan

              Project Sponser: City of Eureka
                                 Eureka, CA 95501
                                 (707) 443-7331 ext. 309

              Landowner: City of Eureka

              Assessor's Parcel Numbers:   7-031-01
                                           7-013-03
                                           7-051-01
                                           7-041-01  (Portion)
                                           7-051-03  (Portion)
                                           7-061-01
                                           7-071-10

              Project Size: 86 Acres

              Zoning: Natural Resource (City of Eureka    LCP Adopted July, 1984)

              Project Location: Sections 28 & 33, T5N,    RIW,.H.M.

              City of Eureka City Council Approval September 29, 1987

                                         TABLE OF CONTENTS

                                                                            Page
               1.0  ENHANCEMENT PLAN SUMMARY

                    1.1 Introduction                                        1-1
                    1.2 Description and Location                            @1-2
                    1.3 Site Analysis                                       1-2
                    1.4 Enhancement Plan                                    1-3

               2.0  PROJECT DESCRIPTION

                    2.1 Introduction                                        2-1
                    2.2   Site Definition                                   2-3
                    2.3   Related Projects and Properties                   2-5

               3.0  SITE  CONDITIONS

                    3.1   Topography & Geology                              3-1
                    3.2   Soils                                             3-2
                    3.3   Hydrology                                         3-4
                          3.31 Tidal Influence / Surface Runoff             3-4
                          3.32 Flooding                                     3-6
                          3.33 Water Quality                                3-9
                    3.4   Vegetation                                        3-13
                          3.41  Overview                                    3-13
                          3.42  Vegetative Description                      3-14
                                3.421 Salt Marsh                            3-14
                                3.422 Brackish Marsh                        3-15
                                3.423 Freshwater Marsh                      3-15
                                3.424 Riparian Wetlands                     3-16
                          3.43  Rare Species                                3-16
                          3.44  Invasive Species                            3-16
                          3.45  Influencing Factors                         3-19
                    3.5   Wildlife                                          3-21
                          3.51 overview                                     3-21
                          3.52 Salt/Brackish Marsh    Area                  3-21
                          3.53  Freshwater/Riparian   Marsh                 3-25
                          3.54  Use by Mammalian Species                    3-25
                    3.6   Mosquito Vectors                                  3-26
                    3.7   Land Use/Access                                   3-28
                          3.71 Site History                                 3-28
                          3.72 Current Land   Use                           3-29
                          3.73  Access                                      @-31

                                           US Department Of Commerce
                                       NOAA Coastal Services Center Library
                                            2234 South Hobson Avenue
                                             Charleston, SC 29405-2413

              4.0 ENHANCEMENT PLAN

                    4.1  Introduction                                      4-1
                    4.2  Site  Analysis and Goal Development               4-1
                         4.21   Topography, Geology, Soils                 4-1
                         4.22   Hydrology                                  4-2
                         4.23   Vegetation                                 4-2
                         4.24   Wildlife                                   4-3
                         4.25   Public Access                              4-4
                         4.26   Maintenance                                4-4
                    4.3  Proposed Enhancement Plan Summary                 4-5
                         4.31 Palco Marsh Complex                          4-5
                         4.32 Paved Drying Shed Area                       4-5
                         4.33   Area West of Railroad Tracks               4-6
                    4.4  Alternatives Considered                           4-6
                    4.5  Proposed Enhancement Plan -
                           Construction Aspects                            4-7
                         4.51 Palco Marsh Complex                          4-8
                         4.52 Paved Dry Shed Area     / Railroad Marsh     4-15
                         4.53 West of Railroad Tracks                      4-16
                    4.6  Operations/Maintenance                            4-17
                    4.7  Monitoring                                        4-18
                    4.8  Permit Requirements                               4-20
                    4.9  Future Enhancement Work                           4-21

              REFERENCES                                                   R-1

              LIST OF APPENDICES

              Appendix A - Notes on Circulation and Sedimentation          A-1
                        B - Vegetation Description/Species List            B-1
                        C - Estimated Construction Costs                   C-1

              MAP 1 Enhancement Plan                          Back Cover

                                        FIGURES AND TABLES
              FIGURES                                                      Page

               1   Project Site Location                                   2-2
               2   Palco Marsh Project Area                                2-4
               3   Tidal Exchange Area                                     3-5
               4   Watershed Areas                                         3-7
               5   Water Levels in Marsh
                      present conditions                                   3-10
               6   Rare Species                                            3-17
               7   Invasive Species                                        3-18
               8   1939 Aerial Photo                                       3-30
               9   Enhancement Plan - Tidal Prism/
                     Storm Runoff
                   a. Tidal Prism                                          4-9
                   b. 2-year Storm                                         4-9
                   C. 100-year Storm                                       4-10
                   d. Feb. 1986, Water Levels                              4-10
              10   Enhancement Plan - Tidal Exchange Areas                 4-11
              11   Enhancement Plan- Conceptual Phase Two                   4-22

              TABLES

               1   Soil Salinities/PH                                      3-3
               2   Drainage Areas                                          3-8
               3   Water Quality                                           3-11
               4   Avian Species List                                      3-22
               5   Mammals List                                            3-23
               6   Enhancement Plan -
                   Response to Tide                                        4-12
               7   Enhancement Plan -
                   Response to Runoff                                      4-12

              RAPS

               I Enhancement Plan                                   Back Cover

               The following maps are available for review at the City of
               Eureka and are at a scale of 1 inch equals 100 feet.

               I Enhancement Plan
               2 Topographic Map
               3 Vegetation Map

             1.0    SUMMARY

                  1.1 Introduction

             The Palco Marsh has been a focus of concern for enhancement
             activities by a number of agencies; the Army Corps of Engineers
             designated the site as an "Area of Importance" to the functioning
             of the Humboldt Bay ecosystem; the California Coastal Commission
             included the Palco Marsh on its list of priority public acqui-
             sition sites; and the City of Eureka designated this site in its
             Local Coastal Plan for acquisition and enhancement activity, and
             requested funding from the Coastal Conservancy for acquisition
             and eventual enhancement improvements.

             The Coastal Conservancy agreed to provide funding to acquire,
             plan and restore the Palco Marsh site with three primary
             objectives:

                  1.  Enhance tidal action in the Palco Marsh.

                  2.  Remove fill in drying shed area and restore to marsh
                      habitat.

                  3.  Assemble land in the project area to improve future
                      management.

             The development of the following Enhancement Plan takes into
             account agency goals, site condition, and subsequent discussions
             with the City of Eureka, the Coastal Conservancy and other
             interested agencies.

             Section 2.0 describes the project site location and its
             relationship to other projects. Section 3.0 includes a site
             inventory and identification of Marsh enhancement opportunities
             and constraints. Section 4.0 contains the principal findings,
             opportunities, constraints and goals developed from this
             information.

             Information compiled in this report was gathered from September,
             @986 through February, 1987. Technical information has been
             included, where appropriate, but for brevity's sake, is
             referenced as separate studies available from the City of Eureka.
             Development of goals and objectives proceeded from the Coastal
             Conservancy's initial goals and were influenced by opportunities
             and constraints inherent to site conditions. These goal  s were
             further defined through discussions with the City of Eur*eka, the
             Coastal Conservancy and the California Department of Fish and
             Game.

                 1.2 Description and Location

            The Palco Marsh project site is located on the eastern shoreline
            of Humboldt Bay at the western edge of the City of Eureka. It is
            surrounded by urban development of three sides: 1) Del Norte and
            Hawthorne Streets and adjacent commercial/industrial uses to the
            north; 2) Broadway Avenue with commercial uses to the east; and
            3) the newly constructed Bayshore Mall to the south. Wes-t of the
            Palco Marsh project site are Humboldt Bay mudflats, central chan-
            nel and the Samoa Peninsula. The Crown Simpson pulp mill is
            located directly across the Bay channel on the Samoa Peninsula,
            1/2 mile west of the subject property.

            The project is bisected by the Northwestern Pacific Railroad
            right-of-way, which traverses north-south across the project
            site. The east half of the site consists of approximately 45
            acres which includes a six acre developed area and a 39 acre
            marsh complex, consisting of approximately 17 acres of salt
            marsh, nine acres of brackish marsh, eight acres of freshwater
            marsh, and five acres of riparian habitat. The western half of
            the project site, 41 acres, consists of tidal flats, a shoreline
            strip of salt marsh and a four acre upland peninsula located just
            south of the end of Del Norte Street.

                1.3 Site Analysis

            Marsh topography, soils and off-site hydrologic conditions have
            not changed much from historical conditions. Vegetation is more
            sensitive to changing environmental conditions, and thus reacts
            more quickly to changes. Because of this, opportunities are
            available to improve the vegetation and consequently wildlife
            habitat values. There are certain factors causing the marshes to
            be under stress and affecting the marsh vegetation density.
            These include poor tidal circulation and retention of storm run-
            off which causes hypersalinity and dissolved oxygen depletion.
            The unhealthy condition of the salt marsh is evident by the lack
            of diversity of the vegetation. Under an improved tidal regime,
            salt marsh areas could be returned to a higher functioning value.
            Information gathered at the drying shed area indicates that,
            depending on the amount of fill removed and the availability of
            future water sources, this area could support wetland vegetation.
            The major problem with the Palco Marsh with regard to wildlife
            use is the lack of tidal circulation in the salt marsh and the
            lack of significant amounts of open water habitat in the brackish
            and freshwater marshes. This results in reduced food production
            for all species of water-related birds and in a lack of water
            surface for landing and take-off for certain waterfowl species
            (e.g. ruddy ducks, greater scaups, cootst and grebes). The
            outcome is both reduced numbers and diversity of wildlife.

            Improving the circulation of tidewater throughout the salt marsh
            will improve its value to wildlife. The lack.of circulation in
            this area causes low food availability for wildlife. organisms

                                          1-2

             normally associated with salt marsh (and good circulation) are
             present in limited areas within the Palco Marsh. These include
             invertebrates which are critical for foraging by shorebirds,
             snowy egrets, etc. An increase in tidal flows would allow the
             redevelopment of this invertebrate fauna; subsequently the
             diversity and numbers of wildlife in the area should increase.

             If a deep water pond (six to nine foot depth) was developed in
             the freshwater/brackish marsh area, there would be an appreciable
             increase in both diversity and numbers of wildlife using the
             area. The important submerged aquatic plants necessary for the
             development of a food base in the pond are present in the resi-
             dual pond left in the freshwater marsh. This would allow water-
             fowl, grebes, coots and mergansers to land, forage and have the
             safety of deeper water for escape from potential predators.
             Herons and egrets would have a foraging area on the edges of the
             pond and would roost near this new feeding area.

             Since mixed commercial/industrial land uses surround the project
             site, adequate buffers are needed to protect/enhance the
             integrity of the marsh environments. The site, at present, has
             uncontrolled access and is used in ways contrary to wildlife
             values. As the project site is restored for wildlife, increased
             interest and subsequent use by the public is anticipated.
             Providing controlled access for compatible public uses will be
             necessary to maintain wildlife values for the site.

                  1.4 Enhancement Plan

             The improvements necessary to accomplish the project goals
             include both improving conditions in the existing marshes as well
             as creating wetlands in non-marsh areas. Control of water within
             the marsh will be accomplished by the placement of larger
             diameter culverts at a lower elevation and channel excavation
             within the marsh. Water levels in the marsh will be adjustable
             by weir structures on either end of the culvert. This will
             increase tidal circulation, and run-off drainage out of the
             marsh. Clearing a one and a half acre area of cattails and
             excavating a deep open water area will provide a more diverse and
             much needed addition to the surrounding marsh habitats.

             The RR Marsh will be graded with channels connecting into the
             Palco Marsh drainage. Portions of the paved area, as well as the
             railroad spur, will be graded to wetland elevations.

             The remaining paved area will be enhanced as a "Phase 2" for this
             project at a time when adjacent water sources become available
             and/or as part of wetland mitigation for development of an
             adjacent coastal dependent industrial parcel (Parcel 4).

             Riparian vegetation will be utilized to screen and buffer
             adjacent land uses, road edges, and parking areas. Public access

                                            1-3

          will be encouraged on the site in ways compatible with wildlife
          needs. Access to the site will include two main entrance
          locations, connected to each other by a pedestrian trail.
          Viewing areas, benches and a picnic site are included in the
          improvements. Access barriers will be provided in necessary
          locations and signs will provide both educational information and
          site use regulations. Riparian vegetation will be utilized to
          screen and provide a buffer from adjacent land uses.

          Project maintenance will be minimum and consist of inspecting and
          maintaining water circulation improvements and public access
          areas. Completion of the construction phase is only the
          beginning phase of this project. Monitoring hydraulic,
          vegetation and wildlife changes, as a result of this project, is
          an important aspect to the project, both in research value and
          for fine-tuning the marsh to ensure a "successful" enhancement
          project. Completion of base data will be necessary prior to
          construction.

                                         1-4

             2.0 PROJECT DESCRIPTION

                  2.1 INTRODUCTION

             Humboldt Bay has experienced a loss of approximately 90% of its
             wetlands. Out of a total of 6t5OO acres in existence in the
             1800's only 600 acres of salt marsh and 40 acres of freshwater
             marsh remained as of 1980. Recent restoration efforts,@funded
             for the most part by the State of California, have increased
             these figures to approximately 700 acres of salt marsh and 100
             acres of freshwater marsh.

             Several agencies have been involved in direct efforts to restore
             wetland areas or enhance degraded wetlands around Humboldt Bay.
             These include the California Coastal Conservancy., California
             Department of Fish and Game, and the U.S. Fish and Wildlife
             Service. Other agencies, such as the California Coastal
             Commission, California Department of Fish and Game, Army Corp of
             Engineers, and locally, the Humboldt Bay Harbor, Recreation and
             Conservation District as well as local municipalities regulate
             development affecting wetland or marine resources.

             The project area has been an area of concern to.a number of agen-
             cies. In 1980, the Army Corps of Engineers comp  leted an
             exhaustive inventory of Humboldt Bay wetlands and designated
             areas into categories based on their resource values
             (Humboldt Bay Wetlands Review and Baylands Analysis, Shapiro,
             1980). The Palco Marsh project area was designated in this
             report as an "Area of Importance" because of its importance to
             the functioning of the Humboldt Bay ecosystem. The California
             Coastal Act mandates wetland protection and enhancement where
             feasible. As a result, the Coastal Commission included Palco
             Marsh on its list of priority public acquisition sites and sup-
             ported the City's application for funds to acquire and enhance
             the site.

             The City of Eureka's Local Coastal Program identifies specific
             areas for wetland restoration projects within City limits. The
             objectives of the program include enhancing the biological
             productivity of the wetlands, minimizing or eliminating conflicts
             between wetlands and adjacent urban uses and providing stable
             boundaries and buffers between upland habitat areas. The Palco
             Marsh project site is specifically mentioned for wetland restor-
             ation.

             The California Coastal Conservancy had been interested in pur-
             chasing the marsh complex for a number of years. Discussions
             with,representatives from Pacific Lumber Company (the landowner)
             @ed to an agreement to preserve the integrity of the marsh. This
             included Pacific Lumber Company (PALCO) divesting their entire
             land holdings in the project area.

                                            2-1

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                                                                                                                                                                  PROJECT SITE LOCATION

                                                                                                                                   2-2                                                                     Figure

              In 1986 the Coastal Conservancy provided the City of Eureka with
              the funding to purchase the Palco Marsh project site. Following
              acquisition, the City of Eureka dedicated an open space easement
              over the Palco Marsh project site to the Conservancy or a manage-
              ment entity approved by the Executive Officer of the Conservancy.

              In addition to providing funding for acquisition of the Palco
              Marsh project site, the Coastal Conservancy will be inVolved in
              funding a project that enhances this area. Enhancement, as out-
              lined by the Coastal Conservancy, would include improving tidal
              action to the 39 acre marsh complex, removing fill on a six acre
              parcel, and assembling parcels of land to improve the resource
              management of the project area. To this end, the Conservancy
              provided funding to the City of Eureka to develop an Enhancement
              Plan. Omsberg & Company and Rising Sun Enterprises were
              contracted to complete a site analysis and develop the Enhance-
              ment Plan for the area. A project team was compiled to assist in
              this endeavor consisting of Dr Robert Willis and Dr Mac McKee as
              project hydrologists, Gail Newton and Associates as project
              botanists and Dr Kitchen as wildlife specialist.

              This Enhancement Plan involved a process beginning with
              identification of preliminary project goals by the Coastal
              Conservancy. Based on this initial direction, a site analysis
              was conducted to identify opportunities for enhancement
              planning. Information compiled in this report was gathered from
              September, 1986 through February, 1987. Further definition of
              goals and objectives were influenced by opportunities and
              constraints inherent to site conditions. Discussions with the
              City of Eureka and the Coastal Conservancy led to a definition of
              goals and objectives which are listed in Section 4.2 of the
              Enhancement Plan.

              This Enhancement Plan, after the City's approval, will be sub-
              mitted and reviewed by both permitting and reviewing agencies
              (California Coastal Conservancy, Humboldt Bay Harbor District,
              California Coastal Commission, Army Corps of Engineers,
              California Department of Fish and Game). The review and
              permitting sequence offers several opportunities for public
              review and hearings.

              The City is currently establishing a non-profit organization that
              would manage the Palco Marsh project, as well as other enhance-
              ment projects planned in the City of Eureka. If the City is
              unable to establish a nonprofit organization to perform this
              function, then the Department of Fish and Game has expressed an
              interest in managing the project area.

                  2.2 Site Definition

              The Palco Marsh project site is located on the eastern shoreline
              of Humboldt Bay at the western edge of the City of Eureka. It is
              surrounded by urban development on three sides: 1) Del Ncrte and
              Hawthorne Streets and adjacent commercial/industrial uses to the

                                             2-3

                                                                                 BROADWAY

                                                                                         RIPARIAN

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              north;  2) Broadway Avenue with commercial uses to the east; and
              3) the  newly constructed Bayshore Mall to the south. West of the
              Palco Marsh project site are Humboldt Bay mudflats, central
              channel and the Samoa Peninsula. The Crown Simpson pulp mill is
              located directly across the Bay channel on the Samoa Peninsula,
              1/2 mile west of the Palco Marsh site.

              The project is bisected by the Northwestern Pacific Rai;71road
              right-of-way, which traverses north-soutb across the project
              site. The east half of the project site consists of approxi-
              mately 45 acres which includes a six acre developed area and a
              39 acre marsh complex consisting of approximately 17 acres of
              salt marsh, nine acres of brackish marsh, eight acres of freshwater
              marsh, and five acres of riparian habitat. The western half of the
              project site, 41 acres, consists of tidal flats, shoreline strip
              of salt marsh and a four acre upland peninsula located just south
              of the end of Del Norte Street. See Figure 2 for location and
              nomenclature used throughout the report.

                   2.3 Related Projects and Properties

              Several other projects, not a part of the Palco Marsh project
              site, are related to the project and addressed in other portions
              of this report. These include: 1) "Parcel 4", a 15 acre parcel
              zoned for Coastal Dependent Industrial Use which was acquired at
              the same time as the Palco Marsh project site; 2) Maurer Marsh, a
              10 acre freshwater marsh between Vigo and Mill Streets, is cur-
              rently in private ownership. The City of Eureka with the Coastal
              Conservancy is currently negotiating title to this wetland
              portion of the parcel 3) a railroad spur and a 1/2 acre triangular
              shaped "RR Marsh", which is currently owned by the Northwestern
              Pacific Railroad but is being acquired by the City of Eureka,, arid
              4) "Wetland Restoration Areas A and B", adjacent to the paved
              drying shed area and belonging to General Growth Inc., are wetland
              mitigation areas constructed as part of the Bayshore Mall project.

                                               2-5

             3.0 SITE CONDITIONS

                  3.1 Topc>graphy and Geology

             The City of Eureka is situated on the edge of a gently sloping,
             broadly rolling terrace that rises from 20 to 250 feet above the
             central part of Humboldt Bay and surrounding tidal flats. Por-
             tions of the City, including the project site, extend onto the
             lowland areas that form the Bay margin (City of Eureka, Human
             Safety Technical Background Study, 1977). According to mapping
             of the California Department of Mines and Geology (1962), the
             project site is underlain by recent alluvium. The upland terrace
             area, east of Broadway, is underlain by the Pleistocene non-
             marine sedimentary deposits of the Hookton Formation, made up of
             loosely-aggregated gravel, sands and clay.

             The project site, located on partially reclaimed tidelands and
             estuarine deposits, is within a mile of the existing mouth of the
             Elk River. The tendency of north coast estuary areas to undergo
             changes in configuration with fluctuating current, runoff and
             sediment deposition characteristics, suggests that sediments on
             the site were influenced by such estuarine movements. Materials
             underlying the project site could be expected to be bay
             sediments, river alluvium and sand dune materials.

             Topographic information was compiled for the project site from
             various existing sources of information. Additional elevations
             were obtained during the site analysis phase of the project. All
             elevations throughout the report will be to City of Eureka's
             datum. Mean lower low water equivalents will be given in paren-
             thesis where noted.

             The topography of the site gently slopes upward from 1.7 feet
             (2.1 MLLW) at the tide gate structure to 10+ feet at Broadway.
             The salt-brackish marsh complex is located between 5.1 feet (5.5
             MLLW) and 6.1 feet (6.5 MLLW) elevation. The freshwater marsh
             area is generally at 6.3 feet (6.7 MLLW) elevation. The filled
             and paved upland area containing the drying sheds is generally
             between 8.0 feet and 10.6 feet elevation.

             Indications for Enhancement Planning

             The location and influence of Humboldt Bay and the Elk River has
             varied throughout the site's history causing site conditions to
             be conducive to re-establishment of wetland habitats. The
             majority of the site remains unfilled; portions are still
             influenced by tidal input or from upland drainages. The-rela-
             tively low gradient of the Marsh, sensitive to small changes in
             water surface elevations, dictates that careful planning will be
             necessary to maintain or enhance the site for a particular type
             of wetland. Elevations present on-site are conducive to an
             increased yet still muted tidal prism. Grading in some areas
             will be necessary to provide channels to distribute tidal input
             or provide adequate drainage.

                                            3-1

                  3.2 Soils

             Lowland areas around the Bay have been subject to extensive dis-
             turbance since the settlement of the area in the 1850's, making
             the nature of native materials underlying the filled and paved
             areas of the site difficult to determine from surface evidence.
             The 1854 U.S. Coast Survey of Humboldt Bay (Bache, 1854) indi-
             cates that the site at that time encompassed higher areas of
             sandy grasslands and lower marsh areas subject to tidal 7inun-
             dation. Though unmapped, a correlation can be made with soils
             found near the mouth of the Elk River. Soils in the Elk River
             area are composed of two mapping units: Sand Dunes (SD) and
             Bayside Silty Clay Loam (Ba6). The "Sand Dunes" classification
             consists of wind-deposited, fine-grained sands. The Bayside
             soils have high clay content and are derived from reclaimed tidal
             marshes at elevations near sea level (McLaughlin and Harradine,
             1965).

             on-site soils data was analyzed by CalTrans during explorations
             in connection with the proposed Eureka freeway in 1965 and 1971.
             CalTrans' investigations include a series of b  'ore holes on a
             north-south trending line through the site. These bore holes,
             ranging in depth from 16 to 55 feet, penetrated extensive layers
             of saturated sands, clays, organic and marine layers, tending to
             confirm what is thought to be the original conditions on the site
             (sand dune, river mouth and bay deposits). Very.wet soils (free
             water present) conditions were encountered at or near ground
             surface for the majority of the holes located on the site.

             Surface soils in the Palco Marsh wetland area were analyzed for
             texture, salinity and pH (see Table 1). These samples exhibited
             a range of texture varying from clay to organic soils. Signs of
             anaerobic decomposition and hypersaline conditions were found in
             the clays associated with the unvegetated salt marsh areas, indi-
            .cating poorly flushed tidal areas; thick organic layers were
             found in the fresh/brackish marsh area.

             Aerial photographs dating back to 1931 and historic maps were
             examined to identify areas where fill in the paved drying shed
             area may exist. It appears that higher upland areas were leveled
             to fill lower tidal areas. Several exploratory holes, dug in
             1986 with a backhoe, indicated that the paved area consists of an
             average of four inches of paving. Sandy grassland soils, as well
             as imported river run gravel, served as the source of fill.
             Bayside silty clay loam was encountered two to three feet below
             the surface in some locations. Groundwater was present
             approximately five feet below the surface, which is consi    stent
             with adjacent wetland elevations (5.0 foot elevation).

                                             3-2

                                            TABLE 1

                                       SOIL PH/SALINITIES

             soil                     Elevation             PH        Salinity (ppt)

             Bay - cordgrass              n/a               6.6             15

             Bay - pickleweed             n/a               6.4             25

             Marsh - pickleweed           6.0               6.4             15

             N. Marsh - mudflat           5.3               6.7             60

             N. Marsh - mudflat           5.3               6.9             50

             Saltgrass - rear             5.3               6.5             30
                         inlet

             Northend - pickleweed        5.5               5.8             25

             Southend - pickleweed        6.1               6.8             25

             Historic slough              5.0               6.5             65

             Brackish marsh               5.7               5.0               5

             Freshwater marsh             4.6               4.7               0

                                              3-3

         01

             indications for Enhancement Planning

             Soils in the existing wetland areas exhibit characteristics that
             would normally be expected, given the present hydrologic
             influences and vegetative cover. Surface soils in the salt marsh
             area could be improved with an increase in tidal flushing, there-
             by reducing salinities and providing suitable conditions for
             natural revegetation by existing salt marsh species. Rdmoval of
             the paving, and a minimal amount of fill in the area surrounding
             the drying sheds, would provide habitat for willows and alders,
             if planted. Other upland species would also expect to colonize
             in the area. Removal of all the fill, as well as 2-3 feet of
             native soil would be necessary to subject the area to enough
             tidal action to establish salt marsh habitat. Freshwater ponds
             could also be established in this area provided an adequate
             source of water is available.

                 3.3 Hydrology

             The Palco, Marsh project site is physically separated from
             Humboldt Bay hydraulics by the existing Northwestern Pacific
             Railroad right-of-way and the City of Eureka's maintenence dike.
             The principal hydrologic inputs to the Palco Marsh include tidal
             influx, urban runoff from areas east of the site, direct preci-
             pitation and ground water discharge.

                      3.31 Tidal Influence/Surface Runoff

             A tidegate, located on the bay-side of the railroad right-of-way,
             has historically limited tidal influence into the Marsh. The
             existence of established salt marsh vegetation in the Marsh indi-
             cates that the tidegate has not been kept in proper working
             order. At present, sediment and debris are keeping the tidegate
             partially open. A 24 inch culvert extends from the tidegate to
             the inland side of the railroad tracks. From this point, tide
             waters empty into a 10 x 20 foot "pool" (see Figure 3). The
             Palco Marsh drains into this pool and receives tidewaters, via
             two 12-inch PVC pipes located on the City of Eureka's maintenence
             dike. Tides in excess of 4.0 feet enter the pool area and fill
             the lateral ditches. Only tides in excess of 5.4 feet enter the
             Palco Marsh, and only for a brief period of time.

          ..During summer months, tidal influence on Palco Marsh is limited.
             Water surface elevation changes of 0.2 feet were measured during
             a tidal range that varied eight feet. This represents an extremely
             muted tidal cycle. This combined with evapotranspiration results
             in hypersaline conditions, soil shrinkage/subsidence and algal
             mats. During winter months, tidal influence is similarly limited
             but influence of surface runoff, as a result of precipitation,
             causes more dramatic changes in water elevations. Observations
             indicate that a one inch rainfall caused water levels in the
             marsh to increase as much as six inches and took several days to
             drain out. (see Figure 5).

                                           3-4

                                                                                                            a)

                                                                                                                                                                                       P
                                                                                                       Railroad
                                                                                                                                                                          Ra Iroa
                                                                                                       Tracks

                                                                                                                                                                         01

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                                              rn        19
                                              <        0
                                          Ox  >
                                                                                                        Fence                                                 Fence...
                                              z                                                                                        >
                                                                                                                                       Z                      Top of Bank
                              36" Sewer        Line
                                                                                                                                                             36"Sewer Line

                                        18" Sewer        Line.
                                                                                      _0               0
                                                                                    I.G.               00
                                                             b                        CD               0- <
                                                                                               M
                              >
                              r-                                                               FO

                              rn
                                                                                                                                                             12"Water Line
                              x            12"Water Line
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                                                           ine,-,

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                              m
                                                                                0          do

                                                                                U)

                              m

             The area of the Palco Marsh is approximately thirty-nine acres.
             Hydrologic systems in the vicinity of the Palco Marsh include 13
             watershed areas (see Figure 4). Of these thirteen areas, only
             input from Drainage Areas 2 through 9 (a total of 197.5 acres)
             drain into the Palco Marsh. Of the total 197.5 acres, drainage
             from approximately 150 of the acres flow into the Maurer Marsh
             (Drainage Area 7) and subsequently into Palco Marsh.

             Drainage Areas 10 through 13, though adjacent to the project,
             drain into Humboldt Bay without entering the Palco Marsh.
             Drainage area acreage, elevations and relevant drainage
             structures are listed in Table 2 for each of the watershed areas
             depicted in Figure 4.

             Groundwater data for the project site are limited. CalTrans test
             borings near South Broadway have indicated shallow (unconfined)
             groundwater resources in the east portion of Palco Marsh at
             approximately 5.0 feet elevation. Backhoe pits, dug in the
             drying'shed vicinity also indicated similar groundwater levels.
             Springs also occur at the base of the bluff-east of Broadway,
             adjacent to the Palco Marsh. The marsh vegetation in the eastern
             portion of Palco Marsh consists primarily of freshwa 'ter species
             supported from these high groundwater sources. The magnitude and
             temporal variation in the groundwater discharge occurring at the
             project site remains unknown.

                       3.32 Flooding

             The existence and severity of flood hazards in the City of Eureka
             were investigated by the Federal Emergency Management Agency
             (FEMA). The study covered all significant flooding sources
             affecting Eureka. As the Management Agency concluded:

                  "Eureka is protected by the Samoa Peninsula from flooding by
                   the open ocean; however, areas of Eureka adjacent to
                   Humboldt Bay are subject to tidal flooding. The highest
                   estimated tidal elevation recorded at Eureka occurred on
                   February 4, 1958. The estimated storm surge height was
                   approximately ... 10 feet above mean lower low water. (MLLW)"

             This elevation was determined in the FEMA study to represent the
             100-year storm tide elevation. Flood-prone areas, as mapped by
             FEMA, lie immediately west of the Northwestern Pacific Railroad
             right-of-way. Within the project site, only the Del Norte Street
             pier and adjacent peninsula, and the shoreline strip of salt
             marsh are mapped as being in the 100-year flood zone.

             Although the Palco Marsh does not appear to be directly affected
             by storm surges, a mathematical model was developed to determine
             the probable variations in marsh water levels resulting from
             extreme hydrologic and tidal events. A combination of a 10 foot
             storm tide and a 100-year precipitation event (3.0 inches of
             rain) resulted in a water level in the marsh of 7.5 feet. This
             would indicate the highest water surface elevations expected in

                                             3-6

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                                                                                                                                                               t
                                                                                                                                                                      tA

                                                             :7.7.

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                                                                                                                                                                                    4*P

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                                                                                   gJ
                                                                                                                                     Mx,
                                                                                                                                                 .. ...     .. ...

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                                                                                                                                                                  !14W44.X

                                                                                                                 .... ........
                                                                                                       . . .....     ....

                                                                                                        a ::::.j

                                                                                                                                                       WATERSHED AREAS

                                                                                                         3-7                                                          Figure 4

                                               TABLE 2

                                    PALCO MARSH DRAINAGE AREAS

                      Area of
          Drainage Drainage Flow
            Area      (acres)    into         Via           Elevation*      Notes

                      38.74    pool       2-12" culverts         5.1       Palco Marsh Area

            pool        -      Bay        24" culvert            3.7       Flow to Bay

              2        3.7       1        18" culvert            6.4       Pocket Marsh #7

              3        6.6       1        1-18" culvert          6.2       runoff drainage
                                          2-8 " culverts                 from City Garbage

              4        3.4       1        surface runoff                   Harbor Lanes
                                                                           Bowling Alley

              5       10.4       1        30" culvert                      enters marsh
                                                                �10.0      adjacent to
                                                                           bowling lanes

              6        4.4       1        surface runoff                   urbanized area
                                                                           north of Vigo

              7       19.0       1        20" culvert                      Maurer Marsh
                                                                 3.6       (10.5 acres) +
                                                                           urbanized area

              8      150.0       7        36" culvert                      Henderson Street
                                                                 11.2      drainage

              9        6.0     Pool       surface runoff                   asphalt/drying
                                                                  -        shed area

            10         7.0     Bay        25" culvert                    Bayshore Restora-
                                                                 6.7       tion Area A

            11         7.2       9        adjustable weir                Bayshore Restora-
                                                                 �7.0      tion Area B

            12        26.4     11         2-18' culverts                   drainage from
                                                                 11.4      Har ris St. south

            13        15.2     9,  11     direct surface                   north parking
                                          runoff                  -        area of Bayshore
                                                                           Mall (partial)

            City of Eureka Datum

                                                  3-8

             the marsh from this single storm event.

             On February 18, 1986, (after a sequence of high rainfall, com-
             bined with a sequence of high tides reaching up to 6.5 MLLW),
             water 'levels in the marsh were above what was produced by the
             mathematical model. These elevations, from observation, were
             estimated to be approximately one foot below the street surface
             at Hawthorne and Felt Streets, making the water surface- elevation
             approximately nine feet. A simulated storm event, representing
             conditions prior to February 18, 1986, was placed into the hy-
             draulic model; results approximated field observations. Approxi-
             mately six inches of rain fell in a seven day period. Although
             none of the individual storms were of a significant nature, the
             cumulative effect on the Palco Marsh was significant. High
             tides, as well as constricted outflow, severely limited discharge
             of fresh water from the marsh. Fluctuation in water levels
             occurring in the marsh, caused by tidal influence and storm
             events are depicted in Figure 5.

                       3.33 Water Quality

             Water quality data have been compiled which attest to the extreme
             variability in water quality factors in Humboldt Bay. Nutrient
             levels, salinity, temperature, and dissolved oxygen levels vary
             with periods of ocean upswelling, tidal changes'l seasonal temper-
             atures and storm runoff. The Humboldt Bay Wetlands Review and
             Analysis (Shapiro, 1980) discusses these general relationships
             and their significance in more detail.

             Land use factors which affect water quality in Humboldt Bay and
             associated tidal marshlands include-discharge from the Arcata and
             Eureka sewage treatment plants, agricultural, silvicultural and
             urban runoff. Restrictions on the harvest of shellfish from the
             Bay result from bacterial contamination from agricultural, sewage
             collection and treatment facility sources. Suspended sediment
             deposition and turbidity in the Bay results primarily from influx
             of turbid ocean water into the Bay, as well as erosion and
             sediment transport from upland watersheds.

             The Palco Marsh is primarily influenced by both surface runoff
             from urban areas and tidal influx. Runoff from urban areas may
             contain toxic chemicals and sediment contributed by residential
             and commercial areas. On-site wetland areas are influenced by
             bay salinity to varying degrees as indicated by the distribution
             of marsh vegetation described in Section 3.4. Although salini-
             ties generally decline with distance from bay discharge outlets,
             localized areas subject to limited inundation, poor drainage and
             flushing, combined with seasonal evapotranspiration, tend to have
             higher salinities than bay waters.

             Six basic water quality parameters were measured during this
             study: temperature, pH, dissolved oxygen (DO), salinity, bio-
             logical oxygen demand (BOD) and suspended materials.
             These water quality parameters are summarized in Table 3.

                                             3-9

                                                          PRESENT CONDITIONS IN MARSH
                                                          WITH VARIOUS PRECIPITATION EVENTS

                       <                                      .......
                                                                        '00 YEAR
                                                                          -------------
                                7                                                                      ------
                                                                        1-0 Y LE

                       ul                                              2- YEAR

                       ILL

                       w

                               4-                                                                    . ................

                                                  20             40              60              80             100

                                                                 TIME IN HOURS

                                                                                   WATER        LEVELS IN MARSH
                                                                                   PRESENT CONDITIONS

                                                                   3-10                                  Figure 5

                                                TABLE 3

                                             WATER QUALITY

          Sample                   Temp.                  Salinity         Suspended      BOD
                     Location        0C      pH    DO         Ppt       Material mg/1     mg/l

            I       Bay            15.5      5.7   5.6        90            .007          31.6

            2       Inlet          16.0      5.9   4.0        55            .008          30.0

            3       500' E.        17.5      6.0   2.7        40            .104          50.7
                    of Inlet

            4       500' E.        17.0      6o2   6.5        60            .003          40.5
                    100' N.
                    of Inlet

            5       Middle of      18.5      6.1   2.4        110
                                                                            .015          40.0
                    N. Marsh

            6       Fresh Water    15.0      5.8   4.0          1           .028          44.6
                    Marsh

            7       Middle of      18.0      6.3   5.5         2.5          .003          29.5
                    S. Marsh

            8       Maurer Marsh   18.0      4.0   3.7         2.5          .001          30.0
                    Drainage

                                                 3-11

           The results indicate some of the important processes occurring in
           the marsh. As would be expected, water temperatures increased
           relative to distance from the bay inlet. An exception to this
           was the sample taken within the freshwater marsh area. Lower
           temperatures would indicate the presence of surface groundwater
           flow. High temperatures and salinity toward the north end of the
           Palco March indicate hypersaline conditions due to poor circula-
           tion and excessive evapotranspiration. Areas subject to poor
           circulation had a high BOD value indicating a lack of oxygen.
           High suspended solids values were found in vegetated areas where
           organic decomposition was occurring.

           Indications for Enhancement Planning

           One of the facotrs that limit enhancement opportunities is the
           high elevation (4.1 MLLW) of the culvert underneath the railroad
           tracks which brings tidal waters from the bay to the marsh.
           Though it would be possible to install a new culvert at a lower
           elevation under the railroad tracks, this alternative is not
           feasible for two reasons. First an 800 foot channel would have
           to be dredged from the main bay channel to the culvert. Second,
           since the Palco Marsh is, for the most part well above 4.0 MLLW,
           major grading and drainage reconfiguration would be necessary to
           take advantage of the extra tidal variation. This would require
           excessive costs and environmental degradation beyond what was
           intended in the original project goals.

           Increasing tidal circulation into the marsh can be accomplished
           by removing existing constraints, including removing the tidegate
           and modifying the area where marsh runoff and tidal influx inter-
           change. Results from the mathematical model indicated that
           either enlarging and/or lowering the elevation of the exchange
           pipes under the maintenance dike, removing the tidegate, or modi-
           fying channel configuration, would not, in themselves, signifi-
           cantly change the conditions in the marsh. A combination of all
           the above would be necessary to effect such a change.

           Surface runoff from the surrounding watershed areas dramatically
           changes the hydraulics of the Palco Marsh during the rainy
           season. The majority of surface runoff entering the Palco Marsh
           is contributed by runoff from 150 acres that enters via the
           Maurer Marsh. During storm conditions, not only does water back
           up into Maurer Marsh due to higher water elevations in the Palco
           Marsh, but outflow is restricted from vegetation surrounding the
           connecting culvert under Vigo Street.

           Flooding problems in the Palco Marsh are a result of constric-
           tions on freshwater discharge from the marsh, rather than tidal
           influx. Increasing the rate of run-off leaving the Marsh,-with-
           out appreciably increasing the volume of tide waters entering the
           marsh, would reduce flooding problems. Modeling results indicate
           that increasing the capacity of the exchange area (Figure 3) will
           improve tidal exchange and drainage without significantly increa-
           sing the intake volume of tide waters during flood conditions.
           This is due mainly to the short period of tidal peaks, restricted
           inflow through the culvert under the tracks and the relatively
           high elevations of the marsh.

                                          3-12

                3.4 Vegetation

                     3.41 Overview

           Wetlands around Humboldt Bay.can be categorized into salt marsh,
           brackish marsh, freshwater marsh, riparian and swamp habitats.
           These classifications occur around the Bay in varying degrees of
           distinction and health.

           In general, the vegetation of the site is typical of marshlands
           around Humboldt Bay (Koplin, et. al. 1984; Newton 1984, 1985a,
           1985b; Seeman 1985, 1986). The salt marshes west of the
           railroad tracks are healthy and diverse. The salt marshes east
           of the railroad tracks are degraded and low in plant diversity.
           Extensive riparian woodlands with diverse understories and fresh-
           water marshes are located on higher elevations toward the east
           side of the marsh complex. Between the riparian woodlands and
           the salt marshes, a large zone of freshwater brackish marshes
           occurs. The assortment of brackish marsh vegetation is unique in
           that most types of brackish marsh located around Humboldt Bay can
           be found within this one marsh complex. This  'is due in part to
           the gradual elevation increase and the inland extent of the
           wetland. As a result, the gradient changes from salt to brackish
           to freshwater marsh.

           The vegetation of the Palco Marsh complex was sampled late in the
           flowering season, between September 29 and October 15, 1986. Due
           to the timing of this study, species composition, quantitative
           variations, and strata height are biased toward the late blooming
           species and/or those species that are distinguishable at that
           time of year. A compiled species list can be found in Appendix
           B.  This species list is representative of the season of this
           study.

           The vegetation patterns of the site were mapped in detail,
           especially the vegetation of the salt marshes located east of the
           railroad tracks. Location and extent of the rare species
           Humboldt Bay gumplant was mapped along with the location of
           invasive exotic species. Figures 6 and 7 depict the location of
           rare species and invasive species, located on the site,
           respectively.

           The Vegetation Descriptions (Section 3.42) describes the general
           factors influencing the current vegetation of the Palco Marsh.
           Each specific vegetation type is described in detail in Appendix
           B; codes used correspond to the 1" = 1001 vegetation map which
           accompanies this study.

           The site contains a large population of the rare plant species
           Humboldt Bay gumplant. Any activity necessary to increase the
           diversity of the salt marshes will not adversely affect this
           population of the rare gumplant. These plants, for the most
           part, occur at high elevations along the west side of the rail-
           road right-of-way. only one specimen was found in the Marsh
           complex.

                                          3-13

            There are four other species of concern that were found on the
            site. The berms surrounding the marshes contain three invasive
            exotic species, scotch broom, french broom, and pampas grass. In
            addition, an invasive plant, the common reed, native to Cali-
            fornia but uncommon around Humboldt Bay, is also found on the site.

                      3.42 Vegetative Descriptions

            The vegetation of the site is briefly descri bed in the following
            discussion. The complete description of each vegetation type (or
            plant assemblage), based on species composition, quantitative
            variations, and structure, has been placed in Appendix B.

                           3.421 Salt Marsh -- SK

            The salt marshes on the site are located both in a shoreline
            strip west of the railroad tracks and in Palco Marsh, east of the
            tracks. The salt marshes west of the tracks contain the usual
            diversity of vascular plants typical of salt marshes around
            Humboldt Bay. Jn this narrow strip of marsh, the three dominant
            salt marsh species, pickleweed ('Salicornia virginica),.cordgrass
            (Spartina densiflora), and salt grass (Distichlis spicata) occur
            together in varying amounts., Occasional throughout these marshes
            are sea lavender (Limonium californicum var. californicum),
            jaume,a (Jaumea carnosa), and arrow grass (Triglochin spp.). The
            rare Humboldt Bay gumplant (Grindelia stricta ssp. blakei) is
            found along the upper edges of this marsh and the salt marsh
            snail (Ovatella myosotis) is common in this location.

            The salt marshes and extensive mud flats east of the tracks are
            degraded and lack much of the diversity common in healthy salt
            marshes on Humboldt Bay. With the exception of the three main
            salt marsh species -- pickleweed, cordgrass, and salt grass --
            none of the other salt marsh species occur in this area. The
            only location that contains a gumplant and a modest population of
            jaumea is a small portion of pickleweed marsh adjacent to the
            inlet channel.

            Orache (Atriplex patula) and brass buttons (Cotula coronopifolia)
            are common in many of the areas east of the tracks, becoming
            dominant in small areas away from the inlet channel. These
            species are typically found in areas that are disturbed or
            severely stressed, likely from oxygen starvation and hyper-
            salinity due to evaporation during the summer months.

            Several areas east of the tracks are dying back at an accelerated
            rate. Aerial photos show that the majority of the die-back has
            occurred since 1981, with significant differences between 1983
            and 1986. Tufts of salt grass from which the substrate has been
            eroded still persist in this area.

                                           3-14

             Since the health of the existing salt marsh east of the tracks is
             one of the main concerns of the enhancement project, the vegeta-
             tion was mapped in detail. Other marshes on Humboldt Bay located
             at similar elevations are usually dominated by pickleweed and
             Jaumea. More detailed vegetation descriptions and codes relate
             to the vegetation map of the site are listed in Appendix B.

                            3.422 Brackish Marshes -- BM

             Brackish marshes form at the interface between the salt marshes
             and the freshwater marshes, therefore exhibiting a wide range of
             salinities that change seasonally. The species composition
             slowly changes as one moves from the areas near the salt marshes
             to the areas near the willow swamps or riparian woodlands. Three
             species of plants which are common throughout these brackish
             marshes are salt rush (Juncus lesueurii var. lesueurii, pacific
             silverweed (Potentilla iigedii ssp. grandis), and water parsley
             (Oenanthe sarmentosa).

             In general, the brackish marshes found on the.site are typical of
             other such marshes around Humboldt Bay. Two types of marshes
             located on the site that are uncommon around Humboldt Bay are the
             pacific rush (Juncus effusus var. pacificus) and the common reed
             (Phragmites communis var. berlandieri) stands. -,The pacific rush
             marsh represents a unique resource;%the common-reed marsh could
             represent a threat to Humboldt Bay marshes. Though none of the
             brackish marshes, or species therein, are rare, the uniqueness of
             this site lies in the quantity and diversity of the marshes
             represented. Within the project site, most of the common types
             of brackish marshes can be found.

             The brackish marshes on the site are separated by species compo-
             sition and structure. The brackish marshes vary from very short
             areas dominated by grass species to the tall stands of slough
             sedge (Carex obnupta).

                            3.423 Freshwater Marshes -- FM

             The marshes included in this section range from the upper edge of
             the brackish marshes to the riparian habitats (or willow swamps).
             The freshwater marshes include two tall, emergent dominated
             marshes and one emergent/floating-leaved marsh. These marshes
             are typical of Humboldt Bay. Some have previously been described
             by Monroe (1973), Newton (in Koplin, et. al. 1984), and Newton
             (1984, 1985a, 1985b).

             These freshwater marshes are extensive within the site and inter-
             grade heavily with adjacent riparian areas. Similar freshwater
             marshes can be found around Humboldt Bay but are usually in
             grazed pastureland areas.

                                             3-15

                            3.424 Riparian Woodlands (or Willow Swamps) -- R

             The riparian woodlands are present in abundance around the east
             edges of the site. Two riparian vegetation types are delineated
             based on the herbaceous layer; one contains typical freshwater
             marsh*species in the understory while the other contains dense
             blackberry hedges and various grass species in the understory.

                       3.43 Rare Species

             The three rare salt marsh species, which commonly occur around
             Humboldt Bay, are Point Reyes' bird's beak (Cordylanthus
             maritimu   sp. palustris), Humboldt Bay owl's clover (Orthocarpus
             castille-loides var. humboldtiensis), and Humboldt Bay gumplant
             (Grindelia stricta ssp. blakei). of these species, only the
             gumplant was found during the surveys conducted between September 29
             and October 15. The bird's beak and the owl's clover are both
             annual species and are not possible to locate at this time of
             year.

             The population of the gumplant is located almost solely along the
             west side of the railroad berm and the adjoining are-as. (See
             Figure 6). only one individual of gumplant was',located in the
             marsh east of the railroad tracks. The total population on the
             site is 4,061 individuals. The current degraded-condition of the
             salt marsh east of the railroad tracks probably,could not support
             either the owl's clover or the bird's beak. However, marginal
             habitat for both species is located in the salt marsh west of the
             railroad tracks. Enhancement activities should create habitat
             acceptable for these two species within the Marsh, if they are
             present near the site.

                       3.44 Invasive Exotica

             The list of exotic species located on the site is extensive
             (including plants such as the cordgrass, himalaya berry, and
             brass buttons). Therefore, this discussion of exotics will be
             limited to the highly invasive species worthy of eradication and
             for which eradication is possible. Eradication of species such
             as himalaya berry would prove costly and futile. The main exotic
             species of concern located on the site are two species of broom
             (Cytisus spp.) and pampas grass (Cortaderia selloana).

             The locations of these species are indicated on Figure 7. The
             majority of the pampas grass is distributed along the railroad
             right-of-way and nearby berms. The species of broom are  Imore
             generally distributed throughout the site, but overall are less
             abundant. Eradication of these species from Palco Marsh should
             also include eradication from adjoining areas, particularly the
             railroad right-of-way.

             One other species of concern located on the site is common reed
             (Phragmites communis var. belandieri). This species is cosmo-

                                            3-16

                                                                                                                          0

                                                                                             cc:l@
                                                   480                         1300
                                 20            --                                                              550
                                                      0  3                                      05
                              3                                 1                    300   200 3     2        1   1   25

                Ma
          I%j   >                                               LOCATION OF HUMBOLDT BAY GUMPLANT ON PALCO MARSH

                                                                  Marks location of Humboldt Bay gumplant
                                                                  (Grindelia strictd ssp. blakei)

                                                                  Numbers refer to number of individual plants
                M
          (D o
                rn
          CY)   U)

                                                                                                                               fC
                                                                                                    CO

                    W
                     f                                                  0

                                                                                                                                                                                                                           NCO

                                                               -k 41

                                                                                                                                                                    I    A    I V L S I    I C 1        0 N P A L C 0 M A R         I
                               rn

                                                                                                                                             a iTi I)a s (4         s    C o r ta d e        a s e        oa n  a
                                                                                                                                             cotch broom @n'd French br-noll)                                  Yt@-stls @op.
                               rn                                                                                                          C nm m o n r e -J             h ra                  c o m mi u n   s v a r       -b e T, I a n d  e r i
                                                                                                                                                                                  in   t p

                               rr)
                               (n

             politan in distribution (Mason 1957); however, its occurrence
             around Humboldt Bay is very limited. On the east coast and
             throughout the interior of California, common reed occurs in
             monotypic stands covering large acreages. The structure of those
             -marshes decreases overall diversity and decreases wildlife
             habitat values. For this reason common reed should be treated as
             an invasive exotic in the Humboldt Bay area and should be eradi-
             cated before it spreads throughout the Bay's marsblands-.

                       3.45 Influencing Factors

             Three main factors influence the vegetation of a wetland: the
             duration of inundation, the chemistry of the water, and the site
             history. More specifically, the duration of inundation refers to
             @oth inundation by tidal action and nundation by direct or
             indirect precipitation. The most important aspect of the
             chemistry is the relative amount of soluble ions in the water.
             The third factor is the history of the site, particularly the
             disturbance history. The 1854 map of the site shows tidal
             marshes on the western edge of the site with small sandy areas
             included. The eastern portion of the site at that time is shown
             as vegetated dunes or grasslands with the very eastern edge
             containing some brush. In 1931 the site east of the railroad
             tracks was under agricultural use. The primary slough patterns
             within the pasturelands follow the same route today as they did
             in 1931. The riparian area near Highway 101 was much less
             extensive than present day.

             It appears that by 1939, the eastern portion of the present day
             brackish marshes was no longer being as heavily plowed, as
             evidenced by the tufts of vegetation. By 1954 the taller vege-
             tation had spread throughout the eastern portion of the marsh and
             the freshwater pond (of which a small remnant remains today) had
             started to develop. By 1962 the pond was fully developed, and
             the salt marshes were present. By 1972, the marshes appeared
             well established, and the riparian area was slowly expandinq.

             One of the more significant events in the vegetation history of
             Palco Marsh occurred during'1981, during the construction of the
             sewer line. The salt marshes located adjacent to Del Norte
             Street and north of the inlet channel began dying back at a
             rapid rate. The difference between the extent of the marsh
             vegetation between 1983 and 1986 is dramatic, some areas having
             diminished by 50% or more. Evidence of the erosion is present in
             the vegetation on the site; isolated1tufts of salt grass can be
             found on the mudflats.

             With all three factors; water, chemistry and history varying
             independently throughout a site, an association of plants is not
             an adequate indicator of the environmental conditions that pre-
             vail, since each species has different tolerances and can grow
             under different conditions. Absolute lines between salt marsh,
             brackish marsh, and freshwater marsh cannot be designated.

                                            3-19

             Indications for Enhancement Planning

             Site conditions, as discussed in the preceding sections, have
             not dramatically changed in regards to topography, soils or
             off-site hydrology. Vegetation is more sensitive to changing
             environmental conditions, and thus reacts more quickly to
             changes. Because of this, opportunities are available to improve
             the vegetation and consequently wildlife habitat valuesz There
             are certain factors causing the marshes to be under stress and
             affecting the marsh vegetation density. These include poor tidal
             circulation and retention of storm run-off, which causes
             hypersalinity and dissolved oxygen depletion. The unhealthy
             condition of the salt marsh is evident by the lack of diversity
             of the vegetation. Under an improved tidal regime, salt marsh
             areas could be returned to a higher functioning value.
             Information gathered at the drying shed area indicates that,
             depending on the amount of fill removed and the availability of
             future water sources, this area could support wetland vegetation.

             The rare species of plants thrive better in healthy salt marshes.
             Anything done to improve the circulation in the salt marsh would
             enhance the area for rare plant establishment. Longterm Protec-
             tion and stabilization of the marsh environment would also
             encourage expansion of rare species habitat. (Newton,86)

             Freshwater marsh areas are slowly succeeding towards replacement
             by other-vegetation development. Large expanses of cattail have
             filled in open water areas and the riparian edge is advancing
             westward towards the freshwater marsh habitat. Deep, open water
             pools that once support emergent species of plants, are now
             limited to the one small open water area.

             The four exotic species of plants mentioned earlier are prolific
             propagators and difficult to control. For the most part Pampas
             grass is limited to the upland areas outside and along the upper
             edge of the Marsh. Reduction and eventual eradication of this
             species will require both removing specimens from adjacent
             property, particularly the railroad right-of-way, and adherence
             to a regular yearly eradication program. The two species of
             broom will require select removal. It is best to do this early
             into the flowering period when it is highly visible and before
             seed production begins.

             The common reed pres ents a different problem in that this species
             of plant is located in the brackish marsh areas and propagates
             both from seed and rhizomes. Efforts to remove plants which cause
             them to break apart and disperse by the tide or wind will only
             aggravate the problem and could cause spreading to other parts of
             the Marsh. As of yet, no known attempts to remove this plant
             species have been made on Humboldt Bay.

             Presently, areas containing common reed are accessible by backhoe
             and or hand removal.

                                            3-20

                  3.5 Wildlife

                        3.51 Overview

             Humboldt Bay is second only to San Francisco Bay area in wildlife
             species diversity and abundance in California. The Bay and asso-
             ciated wetland habitats form an important link in the chain of
             coastal wetlands extending from the Arctic Circle to South
             America. The Bay itself provides a variety of estuarine environ-
             ments which are supplemented and enhanced by the presence of a
             variety of upland, riparian and freshwater marsh habitats.

             Both salt and freshwater marshes have a high nutrient production
             rate, which significantly contributes to the food base of aquatic
             organisms. Because of the decline of wetland areas throughout
             the State, wildlife species adapted for utilizing wetland areas
             are increasingly dependent on the limited areas still remaining.
             The value of both salt and freshwater marshes are significantly
             increased when the two habitats are contiguous.

             Wildlife use of the Marsh was analyzed during November, 1986.
             In addition, census information developed during the Bayshore
             Mall EIR (EDAW, 1984) and other research projects (Gerstenberg,
             1972) was reviewed.

             The Palco Marsh can be divided into three separate areas with
             regard to wildlife use: 1)salt/brackish marsh; 2) freshwater
             marsh; and 3) riparian areas. None of these areas are receiving
             the amount of use by wildlife that would be expected given the
             proximity of the Palco Marsh to Humboldt Bay, the known diversity
             of wildlife in the area, and the lack of these habitats, in
             general, in the greater Humboldt Bay Region. At present the area
             with the richest wildlife fauna is the salt/brackish marsh.

                       3.52 Salt/Brackish Marsh Area

             The salt marsh area presently has the most open water of all
             three types of marsh and, therefore, receives the heaviest use by
             birds; including a variety of shorebirds, herons, egrets, gulls
             and waterfowl (see Table 4). In 1985, black-necked stilts bred
             in the area and the young were successfully raised.    In the
             Falls of 1983-1986, migrating ruffs were observed to use this
             area for feeding and resting. These two species, while generally
             abundant in other areas, are rare in coastal areas such as
             Humboldt Bay and represent unique sightings.

             Throughout the year the principal use of the  salt marsh by birds
             is for feeding and resting. While use of the salt marsh is
             greater than the other marsh areas, it is still below what would
             be expected both in terms of numbers of species and numbers of
             individuals. For example, this area historically had an
             abundance of green-winged teal that could be observed feeding in
             the area. Presently this species is seldom present and, when it
             is, it is represented by only one to four individuals rather than

                                             3-21

                                             TABLE 4

                                       AVIAN SPECIES LIST

                                                                      ACTIVITY
           SPECIES                  TOTAL      AVERAGE      FEED      REST     FLIGHT

           SALT/BRACKISH WILDLIFE
              Large Gulls              139        27.8          4       69         27
              Bonapartes Gulls         17          3.4                           100
              Killdeer                 18          3.6        10        85          5
              Greater Yellowlegs       40          8.0        80        15          5
              Small Sandpipers         72         14.4        72        10         18
              Dowitchers              105         21.0        66        22         12
              Great Blue Heron         15          3.0          9       73         18
              Snowy Egret              21          4.2        74        11         14
              Black-Crowned
                 Night Heron           61         12.2                100
              Common Egret             14          2.8        53        38         19
              Shoveler                 34          6.8        63        26         11
              Green-Winged  Teal      243         48.6                100
              Black Shoulder Kite        5         1.0                           100
              Cooper's Hawk              3          .6                           100
              Black Phoebe               9         1.8        15        85
              Marsh Wren               .33         6.6        45        35         20
              Song Sparrow               7         1.4        35        65
              Raven                      5         1.0                    5        95
           TOTAL - Salt/Brackish      685       137.0

           FRESHWATER KARSH
              Redtailed Hawk, imm        5         1.6                100
              Kestrel-Male               2          .6        30        50         20
              Marsh Wren               66         22.0        45        35         20
              Snipe                      3         1.0                100
              Common Egret             35          7.0                100
              Great Blue Herron          3          .6                100
           TOTAL - Freshwater         114         25.3

           RIPARIAN
              Song Sparrow             22         4.4       52          10         48
              Fox Sparrow              29         5.8       18          11         71
              Chestnut-Backed
              Chickadee                64       12.8        43            8        49
              Black Phoebe             10         2.0       73*         27         73*
              Yellow-Rumped Warbler    40         8.0       19          14         67
              Junco                    52       10.4                             100
              Towndsen's Warbler         7        1.4       26          14         60
              Red-Shouldered Hawk        3         .6                   88         12
              Cooper's Hawk              2         .4                            100
           TOTAL - Riparian           229       25.4

              From 5-day Survey (November 04    - November  18, 1986)

           020:Table 4                          3-22

                                            TABLE 5

                                     KAMMALS (EXPECTED)

                     NAME                                      HABITAT

                     Western harvest mouse                     throughout
                     California mouse                          throughout
                     California vole                           throughout
                     Norway rat                                throughout
                     Black rat                                 throughout
                     House mouse                               edges

                     marsh shrew                               marsh,field
                     Shrew mole                                field edge

                     Brush rabbit                              marsh edge

                     Gray fox                                  edges
                     Common dog                                throughout
                     Raccoon                                   edges
                     Long-tailed weasel                        edges
                     Stripped skunk                            woods

                     California myotis                         woods
                     Red bat                                   woods
                     Big brown bat                             woods

                     Black-tailed deer                         edges

                                             3-23

             the dozens seen in the past. This suggests that changes have
             occurred that have reduced the available food for green-winged
             teal. Snowy egrets feed in the area regularly, but common egrets
             and great blue herons rarely do more than rest. Usually, these
             last two species would forage heavily in a habitat such as this
             if the proper food items were present.

             Humboldt Bay is known to be an important link in Spring@and Fall
             MigrationS of Shorebird5; past studies indicate that the
             Palco Marsh site was extensively used by shorebirds. Long-billed
             dowitchers, greater yellowlegs and willets are @!urrently the most
             common large shorebirds observed feeding in the open water areas
             of the salt marsh. Though an assortment of smaller sandpipers
             were using the open mudflat areas, their numbers were much less
             than normally would be expected to be feeding in the area. Also
             missing were large numbers of marbled godwits and phalaropes
             which would normally be present. This recent decrease in use by
             shorebirds can be considered significant.

             Even though no direct sampling of the food base was conducted
             during this study, observations indicate a lack of necessary food
             items. Mudflat invertebrate fauna, normally present in a salt
             marsh area, is lacking in the Palco Marsh. Marine infauna were
             only found near the inlet channel and the salt marsh snail,
             normally common in salt marsh areas, was absent from the Palco
             Marsh site. Aquatic insect larvae was most likely the main food
             item being utilized.

             Gulls of various species are quite common on this salt marsh and
             spend a great deal of time resting in the shallow water areas.
             Their abundance is due largely to the adjacent City Garbage
             Company of Eureka transfer station. However, Bonaparte's gulls
             use the area and feed in the marsh itself and Sabine's gulls have
             been observed in the area during migration. In particular, the
             Sabinets gull has been seen there during severe storms at sea and
             has appeared to seek refuge in the area. Use of the area by the
             more common gull species (California gull, ring-billed gull,
             herring gull and Western gull) will remain heavy as long as the
             transfer facility is in the area.

             The group of birds most conspicuously absent is the waterfowl.
             The only species observed regularly in the salt marsh were a few
             green-winged teal, shovelers and pintails. There are about a
             dozen species of ducks alone (eg. mallard, gadwall, etc.) that
             one would expect to see in the salt marshes around Humboldt Bay,
             The reasons they are not present are not completely clear, but a
             lack of suitable foods, poor water circulation, and lack--of any
             deep water (six to nine foot depth) are the most likely
             explanations.

             The brackish marsh is immediately adjacent to the salt marsh and
             has little open water at any time. This habitat is used almost
             exclusively by both species of egrets, great-blue herons and
             black-crowned night herons for roosting. Brackish marshes with
             more open water are heavily used in other parts of Humboldt Bay

                                            3-24

             for foraging by these ardeids, by numerous species of shore birds
             and large numbers of waterfowl. The lack of open water reduces
             the available food and, therefore, the value of this area for
             wildlife.

                       3.53 Freshwater/Riparian Marsh

             The freshwater/riparian marsh area has virtually no open water
             and almost no use by wetland-related species of birds (Table 4).
             The primary wetland species present in the  area is the marsh
             wren. It's use of the area is year-round,   with a significant
             breeding population present in the summer. Some of the larger
             waders (common egret and great-blue heron)  use this area for
             roosting and will forage on the rodents in  the habitat. In
             addition, redtailed hawks, cooper's hawks,  kestrels and black-
             shouldered kites make limited use of this area's rodents. Based
             on observed captures, it would appear that the most common
             species of rodent is the California vole.

                       3.54 Use of Palco Marsh 1?y Mammalian Species

             No trapping studies were conducted in any of the three marsh
             areas to determine population levels of rodents or other mammals.
             Larger mammals' use of the area was primarily observed to occur
             along the Bay's edge, as well as in the freshwater marsh area.
             This area receives heavy use by gray foxes, raccoons and domestic
             cats. Signs of occasional use by deer were also observed.
             Mammals expected to be found in this area are listed in Table 5.

             Indication for Enhancement Planning

             The Palco Marsh has a great potential for wildlife use that is
             currently not being observed in the area. The general location
             next to the bay and adjacent wetlands, as well as the size and
             variation of the marshes all contribute to the uniqueness of the
             Palco Marsh. Since many of the wetland areas surrounding the Bay
             are limited in their lateral extent they tend towards narrow
             habitat ranges and often monotypic types of wetlands. Even
             though the general distribution of marshes in Palco Marsh, from
             salt marsh in the west to riparian habitat in the east, occurs in
             a short distance, a unique balance exists. For the various
             species of wildlife utilizing the area, the site offers resting
             and feeding areas, nesting and freshwater sources, refuge from
             storms and, presently, mudflats exposed even at high tides.

             @t would be difficult to justify expansion of one type of habitat
             in favor of another. Freshwater marshes are limited around
             Humboldt Bay, and as seen at Arcata's freshwater marshes and
             oxidation pond, are well used throughout the year. Though a case
             could be made to expand the freshwater marsh area, adjacent
             freshwater marsh areas (Maurer, Bayshore Mall Restoration Area 2)
             offer ample opportunities for future increased use. The best use of

                                            3-25

              the site seems to be in maintaining a balance of the diverse
              range of habitats present. Therefore, the best opportunities to
              enhance the site lie in correcting the problems within the Marsh
              ..to provide higher quality habitat.

              The major problem with the Palco Marsh with regard to wildlife
              use is the lack of water circulation in the salt marsh and the
              lack of significant amounts of open water habitat in the brackish
              and freshwater marshes. This results in reduced food production
              for all Species of water-related birds and in a lack of water
              surface for landing and take-off for certain waterfowl species
              (eg. ruddy ducks; greater scaup, coots, and grebes). The outcome
              is both reduced numbers and diversity of wildlife at the Palco
              Marsh.

              Improving the circulation of tidewater throughout the saltmarsh
              will improve its value to wildlife. The lack of circulation in
              this area causes low food availability for wildlife. organisms
              normally associated with salt marsh-related mudflats (and good
              circulation) are absent in the Palco Marsh. These include inver-
              tebrates which are critical for foraging by shorebirds, snowy
              egrets, etc. An increase in tidal flows would allow the rede-
              velopment of this invertebrate fauna; subsequently the diversity
              and numbers of wildlife in the area should increase.

              If a deep water pond (six to nine foot depth) was developed in
              the freshwater/brackish marsh area, there would be an appreciable
              increase in both diversity and numbers of wildlife using the
              area. The important submerged aquatic plants necessary for the
              development of a food base in the pond are present in the resi-
              dual pond left in the freshwater marsh. This would allow water-
              fowl, grebes, etc. to land, forage and have the safety of deeper
              water for escape from potential predators. Herons and egrets
              would have a foraging area on the edges of the pond and would
              roost near this new feeding area. If more ponds were developed,
              a breeding waterfowl population might occur in the area. Otters
              commonly use the Bay adjacent to the Palco Marsh. If significant
              areas of open water were developed in the various types of marsh
              then it would be reasonable to expect otters to make occasional
              use of the area. Other species of mammals would be unaffected by
              alterations of the three habitat types present in the Palco
              Marsh.

                  3.6 Mosquito Vectors

              Though mosquito problems are generally not significant around
              Humboldt Bay, sporadic outbursts, generally associated with tidal
              pools, do occur. The most significant problem area on the Bay is
              at the Palco Marsh site, where its location, upwind from a large
              population center, amplifies the situation (Strickland, pers.
              com.)

              The County Public Health Department has been monitoring and
              treating the Palco Marsh area for the past six years (from May to

                                            3-26

             September) to assure the minimization of mosquito production.
              (Prior to this time the City,of Eureka managed this task.) The
             primary problem species in this area is the mosquito, Aedes
             dorsalis, a vicious biter of humans with the capacity '&f migra-
             ting up to 20 miles from its breeding habitat (Strickland, pers.
             com.). This is a brackish flood water mosquito which lays its
             eggs on dry land subject to infrequent tidal inundation. The
             best habitat would be shallow depressions that are filled at a
             high high tide and left standing for ten days. This species of
             mosquito hatches from May to September and is a prolific breeder.

             The area which contains the type of habitat favored by this
             mosquito is located in the southwest corner of the Palco Marsh,
             just north of Vigo Street. Tidewaters enter the marsh and move
             towards the south end of the marsh, flooding the area via several
             ditches. Freshwater run-off from the Maurer Marsh, after cross-
             ing under Vigo Street, drains towards the west and subsequently
             into the southwest corner. This combination causes the necessary
             breeding conditions.

             Source reduction is the most successful mosquito abatement
             method7  Either eliminating tidal influence into this area or
             -improving tidal action (where standing brackish flood water would
             not occur) would be the best control for this species. The Marsh
             has been successfully treated regularly for the past two years
             using a bacterial larvacide "BT Formulation" (Bacillus
             thruingiensis var. israelensis). This is non-toxic to other
             aquatic organisms, being specific for the destruction of mosquito
             larvae. other methods such as lateral ditching have been used or
             are available but have not been found to be cost-effective.

             One suggestion made by the County Health Department was to provide
             nest boxes that would attract violet-green swallows or other
             insectivorous birds. If this proves to be a feasible alternative,
             local service groups could be contacted to further assist in this
             endeavor.

                                            3-27

                  3.7 Land.Use/Access

                       3.71 Site History

             Lowland areas around Humboldt Bay have been subject to extensive
             disturbance since the settlement of the area in the 1850's. The
             1854 U.S. Coastal and Geodesic Survey of Humboldt Bay (Bache,
             1854) indicates that the site at that time encompassed areas of
             sandy grasslands and lower marsh areas subject to tidal
             inundation. At that time, existing settlements included
             Bucksport to the south, and Fort Humboldt to the east (EDAW,
             1984).

             By 1870, some of the wetlands between "A" Street in Eureka and
             Bucksport had been diked and reclaimed for agricultural pasture.
             The dikes were improved and used in 1901 for the Northwestern
             Pacific Railroad (EDAW, 1984); these diked areas included the
             Palco marshes. The Palco marshes originally consisted of tidal
             sloughs and salt marsh, but the placement of fill for the rail-
             road right-of-way subsequently caused retention of runoff and the
             subsequent development of fresh/brackish marsh complexes.

             After diking, the Palco marsh area was used for pasture.
             Remnants of fenceposts and lines are still evident in recent
             aerial photos and site reconnaissance. This area was part of the
             larger Russ Ranch, which was located on top of the bluff east of
             Broadway Avenue. During this time, the Dolbeer'& Carson Lumber
             Company was offloading logs from railcars into the Bay from a
             wharf built for that purpose; remnants of this wharf can still be
             seen in the Bay just west of the Palco marsh. Logs dumped at
             this location were floated up to the mill near the Carson Mansion
             site.

             In the 1870's, the South Park Race Track was built in an area
             near Broadway and Wabash. This site was used for both horses
             and, later, automobiles. The area at the extreme northern end of
             the Palco marsh was used for pasturing horses that raced at the
             track. A boxcar, remnants of which can be seen today, was moved
             on to the site to store hay. (Poyfaire, pers. comm.)

             The Holmes-Eureka Mill was established in 1903 on "ten acres of
             sand dunes" located south of the project site. The original
             plant employed 40 workers. By the 1920's, Holmes-Eureka was a
             "highly mechanized modern plant, covering 50 acres, employing
             over 500 men, and engaging in the "world-wide export" of Humboldt
             County redwood lumber. The plant was primarily located between
             the Bay and the railroad right-of-way at the Parcel 4 location
             and along the shoreline. Areas east of the railroad were used
             for log and lumber storage (Sanborn Insurance Maps of Eureka,
             1920; Steenfott Collection).

             From 1930 to 1950, the Eureka Lumber and Crossarm Company built
             cross arms for telephone poles and other uses on the site north-
             west of Mill Street. The existing drying sheds in this area were
             built in 1958 and 1959. The Pacific Lumber Company bought the

                                            3-28

             site in 1959 and used it more or less continuously until 1983,
             for the drying and storage of lumber. During this period, the
             site was substantially graded, creating a series of basins and
             berms throughout portions of the property (LSA, 1986).

             The Palco Marshes, though, remained unfilled. Comparison of
             recent aerial photographs with his@@oric maps show that the
             western portion of the marsh retained its topographic cliarac-
             teristics (present over one hundred years ago), as evidenced by
             the cut-off slough and associated drainages. (See Figure 8).
             Since at least the beginning of this century, with the diking for
             agricultural use and placement of the railroad right-of-way, the
             Palco Marsh has been influenced by retention of some upland run-
             off and limited saltwater intrusion from the Bay.

             In the early fifties, Hawthorne Street, off Broadway, ended
             approximately where the current City Garbage Company of Eureka
             office is now located. A house was located there, and the owner
             raised and sold chickens. Mr. Tom Hall, involved in construction
             and demolition of bridges and buildings, improved the road
             (filled the marsh) to where Hawthorne Street turns into Felt
             Street. Here, a circular road was constructed for storage of old
             trusses and timbers from Hall's construction business. This area
             was bermed and buffered from the marsh as part of conditions for
             City Garbage Company's Coastal Development Permit in 1978.
             (Poyfaire, pers. comm.) Drainage from City Garbage is filtered
             through sand prior to entering the marsh. (Linda Locklin;
             Coastal Commission, pers. comm.)

             In the 1940's, a twelve inch water main was installed  just east
             of the railroad tracks. This new line, enclosed in a    raised
             berm, runs along the western edge of the Palco Marsh from Del
             Norte Street to Vigo Street, before turning west towards the
             track. This fill and drainage alteration subsequently minimized
             tidal influence and altered the vegetation in the marsh.

             In 1981, both a 18" and a 36" sewer main was installed adjacent
             to the water main, connecting the defunct McCullens Avenue plant
             to the new Eel River Treatment Plant. These sewer mains were
             placed in the maintenance dike housing the water line, from Del
             Norte Street to just north of the RR Marsh, where the lines run
             towards and follow the railroad right-of-way. This caused the
             culvert, which previously drained the marsh, to be removed and
             two 12" PVC pipes to replace it at a higher elevation.

                       3.72 Current Land Use

             Land uses adjacent to the site generally consist of commercial/
             industrial development. To the north is the Halvorson "Flea
             Market" Building, City Garbage of Eureka (solid waste refuse
             transfer site) and Harbor Lanes Bowling Alley. Del Norte Street
             Pier, an unused dock needing repair, is located at the north-
             western side of the project site. Along the eastern edge (on
             either side) of Broadway Avenue are commercial uses   including

                                            3-29

                                                                                                       @A

                                                                                                                                      till

                                                                                                              -7,

                                                                                                                                               Ike.

                          NO%

                                                                                         zam

                         IV
                 W-M

                  Alt                                                                                      4

                                                                                                            1939 AERIAL PHOTO

                                                                                                                          Figure 8

              equipment rental, truckstop, motels, and retail stores. Several
              -parcels zoned for commercial services uses are vacant or under-
              developed. The Maurer Marsh, a 19 acre parcel consisting of ten
              acres of freshwater marsh and 9 acres of filled and/or developed
              land, is located east of the drying shed area. The Bayshore
              Mall,-located south of the project site, is currently being con-
              structed; completion date is estimated for November, 1987. Two
              wetland mitigation areas for the Bayshore Mall encompass both the
              east and west edges of the paved drying shed area. These, for
              the most part, have been restored and replanted with wetland/
              riparian vegetation.

              The Palco Marsh area is currently used for bird watching, social
              gatherings, jogging, walking, and retriever training. Clamming
              and some incidental fishing occurs in the bay adjacent to both
              Del Norte Street and Truesdale Street.

              Other uses observed include hunting, pistol shooting, camping and
              garbage dumping. Vacant boxcars on the railroad lines show
              evidence of past and present transient use. These "sleeping
              areas" also occur within the brush vegetation along the borders
              of the project area.

                        3.73 Access

              Many access points into the Palco Marsh site currently exist. A
              person can drive to or near the site by using Railroad Avenue,
              Del Norte Street, Hawthorne Street, Broadway Avenue, Vigo Street
              or Mill Street. Pedestrian use, in addition to the above-
              mentioned roads, occurs from Truesdale Street through the Mall
              construction site, and/or along the Northwestern Pacific Rail-
              road tracks. The City's Maintenance dike between Del Norte and
              Vigo Streets provides access both along and into the marshes.
              Many of the areas within the marsh complex show signs of pede-
              strian use.

              Indications for Enhancement Planning

              Since mixed commercial/industrial land uses surround the project
              site, adequate buffers may be needed to protect/enhance the
              integrity of the marsh environments. The site, at present, has
              uncontrolled access and is made use of in ways contrary to wild-
              life values. As the project site becomes restored for wildlife,
              increased interest and subsequent use by the public is a. 'ntici-
              pated. Providing controlled access for compatible uses will be
              necessary to achieve wildlife values for the site.

              Access from public streets, where adequate parking is available,
              should be encouraged. Parking could be made available along and
              at the end of Del Norte Street. Vigo Street, in its unimproved
              state, does not have parking available along its width. Should
              commercial properties be further developed, street improvements,
              including parking lanes could be required. Vehicular access, as

                                              13 - 1@ I

              well as parking could be made available at the west end of Vigo
              Street. At present, no public easement is available from Mill
              Street, the Bayshore Mall, nor the Northwestern Pacific Railroad
              right-of-way. Access from these locations should be discouraged
              until adequate rights are obtained. Given the access opportu-
              nitie*s available, no need for additional access points are
              warranted at this time.

              On-site pedestrian access includes Vigo Street and the main-
              tenance dike from Vigo Street to Del Norte Street. Views of the
              site are also available from the Del Norte Street peninsula.

              In order to maintain a more perfect union between wildlife and
              people, some effort to control use will be necessary. One of the
              obvious and simple, though expensive methods, would be to place
              fencing around the perimeter of the marsh. This would resolve
              most of the problem at the expense of sacrificing the aesthetic
              value of the area. Other methods are available and have been
              used successfully that not only protects wildlife values but also
              provides an aesthetically pleasing environment that allows people
              the opportunity to enjoy the area for its natural beauty. These
              methods, such as vegetative buffers, ditching along the perimeter
              of the marsh, trail improvements and signs, combined with the
              increase in public use and surveillance all help to define the
              borders for public use.

              Access along the railroad rigbt-of-way has been used by people,
              bicycles, motorbikes and four wheel drive vehicles. This is also
              true for Mill Street. A combination of ditching and vegetative
              plantings could be used to limit access to desired areas.

              A combination of bumper logs, curbing and vegetation
              should be used to define parking areas. Picnic areas should be
              located near parking areas. A trail along the top of the main-
              tenance dike between Vigo and Del Norte Streets should be clearly
              defined. Lateral ditching on both sides of this dike would dis-
              courage entrance into the marsh. The project site on the east
              side of the railroad right-of-way could be fenced and/or planted
              in areas where ditching does not now occur.

              The railroad spur, located near Vigo Street, also allows access
              from the railroad right-of-way. if this spur becomes part of
              this project, the spur should be removed and the berm graded to
              wetland elevations. If this spur remains outside of the project,
              limited fencing , ditching and vegetative plantings should be
              implemented.

              Past land use has caused an accumulation of debris throughout the
              project site. This gives the image of a neglected area and
              encourages further degrading activities, as people's perception
              of an area may influence their treatment of it. As such, a con-
              certed effort should be made to clean up these areas and
              discourage continued misuse.

                                             3-32

             The Del Norte Street Peninsula, approximately four acres, is
             bordered by Del Norte Street at the north, the Bay on its west
             and north sides, and a dredged, drainage/tidal channel along its
             eastern edge. This area consists of a filled wetland area
             presently topped with grasslands, shrubs and a disused gravelled
             and/or paved road. Access to this area from Del Norte Street is
             limited by an open ditch and broken concrete rubble. Alarge
             gravelled# area, adjacent to this site, provides parking adjacent
             to the Bay and for pedestrian access to the pier ruins at the end
             of Del Norte Street. Eureka's LCP identifies this area for
             coastal access and has hopes of someday repairing the pier struc-
             ture.

             Periodic dredging of the drainage channel has been necessary in
             the past and will probably be needed sometime in the near future.
             This necessitates continuous, though periodic, access for inci-
             dental dredging and maintenence purposes adjacent to the channel.

              4.0 ENRANCENEWT PLAN

                   4.1 Intrc>duction

              The development of the following Enhancement Plan takes into
              account agency goals, site conditions, and subsequent discussions
              with the City of Eureka, the Coastal Conservancy and other
              interested agencies.

              The Palco Marsh has been a focus of concern for enhancement acti-
              vities by a number of agencies; the Army Corps of Engineers
              designated the site as an "Area of Importance" to the functioning
              of the Humboldt Bay ecosystem; the California Coastal Commission
              included the Palco Marsh on its list of priority public acquisi-
              tion sites; and the City of Eureka designated this site in its
              Local Coastal Plan for acquisition and enhancement activity. The
              City of Eureka requested funding from the Coastal Conservancy for
              acquisition and eventual enhancement improvements.

              The Coastal Conservancy agreed to provide funding to acquire, plan
              and restore the Palco Marsh site with three primary objectives:

                   1.  Enhance tidal action in the Palco Marsh.

                   2.' Remove fill in drying shed area and restore to marsh
                       habitat.

                   3.  Assemble land in the project area to improve future
                       management.

              The initial enhancement phase involved a site inventory and
              identification of opportunities and constraints. This was
              completed in Section 3.0. The principle findings and oppor-
              tunities for enhancement planning, summarized with goals
              developed by subject area, are listed below.

                   4.2 Site Analysis Results and Goal Development

                        4.21 Topography, Geolocjy and Soils

              Site topography, geology and soils are suitable for wetland
              restoration. Excavation will be necessary in some areas to pro-
              vide channels to distribute tidal input in the salt marsh area
              and establish elevations which will provide open water in the
              freshwater marsh area. The paved drying shed area, which is
              several feet above native wetland soils, will require significant
              amounts of material to be graded to wetland elevations. Fill
              will be required for planting along proposed roadside buffer
              areas. Construction activities could subject wetland soils to
              compaction.

                   1. Improve channel capacities to minimize restrictions on
                       tidal input.

                                             4-1

                    2.  Establish substrate elevations for a 1.5 acre pond conducive
                        to open water habitat in the freshwater marsh.

                    3.  Remove fill at drying shed area to expose native soils
                        and establish elevations favorable to wetland development.

                    4.  Design proposed improvements to minimize grading and
                        equipment operation within existing marsh areas.

                    5.  Utilize construction methods that minimize
                        compaction (e.g. dragline, crawler tractor). Utilize hand
                        ditching where feasible.

                         4.22 Hydrology

              Tidal  influx and runoff within the Palco Marsh are inhibited by a
              faulty tide gate, inadequately sized and improperly placed water
              exchange pipes, and inadequately sized channels for internal
              water distribution. Groundwater conditions appear favorable for
              establishment of freshwater and brackish marsh systems. Flooding
              conditions within the Marsh are primarily due to restriction in
              run-off drainage from the site. Water quality problems resulting
              from on-site conditions will improve with increased tidal
              circulation.

                    1.  Improve tidal circulation to Palco Marsh by removing
                        existing tide gate and install larger capacity pipes at a
                        lower elevation across the existing City maintenance road.

                    2.  Make selected improvements to existing drainage channels
                        and construct new drainage channels to improve circulation
                        within the salt marsh area.

                    3.  Construct weirs, culverts and other water control
                        devices as needed to maintain hydrologic conditions
                        favorable to planned vegetation improvements.

                    4.  Design new water exchange improvements to avoid
                        increasing flood event water elevations.

                    5.  Design channels and weirs to promote scour of natural
                        drainage features in the Marsh that have filled with sediment.

                         4.23 Vegetation

              Salt marsh vegetation west  of the railroad is healthy and
              diverse; east of the tracks, it is degraded and low in diversity
              due to inadequate tidal circulation and insufficient runoff
              drainage. This has caused large areas of pickleweed and salt-

                                               4-2

              grass to die back, leaving bare mudflat areas. Brackish marsh
              vegetation is highly diversified in some areas. Existing fresh-
              water marsh vegetation is dense and has choked almost all open-
              water areas. Riparian vegetation along the east side of the
              marsh site is encroaching westward into the freshwater marsh
              habitat. Freshwater marsh vegetation distribution is at least
              partially fed by near surface groundwater resources. The drying shed
              area and other upland areas presently supports no wetla-nd habitats.
              Invasive exotic species have become established in several loca-
              tions in the marsh, as well as upland areas. Populations of rare
              plant species, located outside of degraded salt marsh areas and
              west of the railroad right-of-way, will not be affected by.
              Enhancement activities should encourage further development.

                   1.  Maintain existing overall vegetation patterns within the
                       Palco Marsh complex.

                   2.  Improve degraded salt marsh conditions in the Palco
                       Marsh to pre-1981 conditions or better by hydraulic
                       improvements and natural plant propagation.

                   3.  Provide approximately 1.5 acres of submergent marsh
                       (open water) area in existing cattail dominated habitats and
                       in the Palco Marsh.

                   4.  Rehabilitate RR Marsh to provide salt marsh habitat
                       adjacent to existing salt/brackish marsh habitat.

                   5.  Excavate existing upland areas along railroad spur to
                       RR Marsh habitat.

                   6.  Provide riparian screening along roadways and commercial
                       development.

                   7.  Reduce or eliminate existing invasive exotic plant
                       species populations to the extent feasible.

                        4.24 Wildlife

              Wildlife use of salt marsh habitat at the Palco Marsh is
              extremely low, both in numbers and diversity. This is primarily
              due to the lack of adequate invertebrate food sources resulting
              from poor tidal circulation. Use of freshwater/brackish
              marsh habitat by wildlife is low due to the lack of open water
              areas. None of these areas are receiving the amount of use by
              wildlife that would be expected, given its location to the Bay
              and surrounding areas.

                   1. Provide open water areas for waterfowl habitat.

                   2. Improve density of salt marsh vegetation in Palco Marsh
                       as habitat for aquatic invertebrates.

                                             4-3

                   3.  Limit public access improvements to margin areas and
                       design to limit wildlife disturbance.

                   4.  Design channel improvements and ditching to limit public
                       access into wetland areas.

                   5.  Develop and adopt area use regulations which rimit
                       disturbances which adversely affect wildlife use.

                   6.  Provide approximately 1.5 acres of submergent marsh
                       (open water) area in existing cattail dominated
                       habitats.

                   7.  Provide riparian screening along roadways and commercial
                       development.

                   8.  Design marsh areas in the paved drying shed area to
                       maximize wildlife habitat values by removing paving,
                       fill, grading and providing an adequate water source.

                       4.25 Public Access

             Existing use of site varies widely in type, amount and occur-
             rance. The enhancement of the proposed marsh will eventually
             result in increasing the number of visitors to the area. Many
             current uses now conflict with anticipated enhancement goals.
             Access routes are undefined, unimproved and abundant, allowing
             for degradation of marsh habitats and wildlife disturbance.

                   1.  Encourage amounts and types of public use which are
                       consistent with enhancement goals in areas which are
                       compatible with wildlife habitat use.

                   2.  Provide controlled public access and wildlife viewing
                       areas consistent with the maintenance of marsh resource
                       values.

                   3.  Develop a small parking area and interpretive
                       signs at Vigo Street just east of the marsh complex.

                   4.  Develop a small parking area, trails, viewing areas and
                       picnic sites at the foot of Del Norte Street.

                       4.26 Maintenance

             As the project's maintenance would be the responsibility of the
             City of Eureka, maintenance costs should be minimized.

                   1. Design improvements to minimize maintenance reau,'rements
                       and law enforcement demands.

                   2.  Provide attractive public access and viewing areas by
                       initially clearing debris followed with regular maintenance.

                   3.  Perform preventive maintenance as needed to maintain
                       target habitats and prevent re-invasion by exotic plant
                       species of vegetation.

                   4.  Upon project construction, institute a program to
                       monitor restoration progress, identify shortfalls and
                       take corrective action.

                   4.3 Proposed Enhancement Plan Summary

              The improvements necessary to accomplish the previously listed
              goals include both improving conditions in the existing marshes,
              as well as creating wetlands in non-marsh areas. The following is
              a summary of the main enhancement implementations by project
              area. A map delineating the improvements (Map 1) is located at
              the back of this report. Associated cost estimates are listed in
              Appendix C.

                        4.31 Palco, Marsh Complex

                   1.  Remove tide gate.
                   2.  Construct an inverted siphon under the City maintenance
                       dike.
                   3.  Excavate perimeter channel improvements, extend hand dug
                       channels as necessary.
                   4.  Construct culverts under maintenance dike to allow tidal
                       influx to RR Marsh.
                   5.  Remove railroad spur and grade to marsh elevations.
                   6.  Clean out channel between RR Marsh and culvert under
                       railroad tracks.
                   7.  Remove exotic vegetation and excavate channels in RR
                       Marsh.
                   8.  Replant excavated salt marsh vegetation in Palco Marsh,
                       RR Marsh and along channels, as appropriate.
                   9.  Excavate permanent open water area in cattail/common
                       rush vegetated areas; provide resting islands; provide
                       low dike around open water area; provide adjustable weir.
                  10.  Elevate and maintain existing maintenance dike for public
                       access and periodic maintenance.
                  11.  Remove exotic plants initially, maintain eradication
                       yearly.
                  12.  Plant riparian buffer areas along road edges, adjacent
                       properties and around parking area for screening.
                  13.  Access improvements
                             - gravel trail, gates, signs and benches along
                               maintenance dike and Vigo Street;
                             - sidewalks along Del Norte Street, Felt Street
                               and Broadway Avenue.

                        4.32 Paved Drying Shed Area

                   1.  Remove drying sheds and other debris.
                   2.  Remove 40'wide strip of paving outside of proposed
                       parking area, berm and plant with riparian buffer.

                   3.  Provide vehicular access barriers where necessary.
                   4.  Use remaining paved area for drying dredge spoils from
                       excavation of channels and open water area.
                   5.  Retain majority of paved area to be removed as part of
                       "Phase 2" of project.

                        4.33 Area West of Railroad Tracks

                   1., Provide public access improvements including parking,
                       sidewalks information kiosk, picnic area, trail, and an
                       elevated viewing area.
                   2.  Provide maintenance access for periodic removal of sedi-
                       ment from drainage channel in the least
                       impacting manner.
                   3.  Provide a temporary dredge spoils drying area
                       adjacent to Del Norte Street.

                   4.4 Alternatives Considered

             Several alternatives were looked at within the Palco Marsh
             complex but not chosen for this project. These included major
             elevation changes in the existing marsh as well as major shifts
             in the amounts of different habitat types. Since the goal was to
             enhance existing wetland systems, these went beyond what was
             necessary. In addition, large scale restoration projects not only
             disrupt existing wildlife use but also have questionable success.

             Several alternatives were considered for the paved area that
             involved grading for varying degrees of salt/brackish or
             freshwater marsh habitats, depending on the source of water
             utilized. Several nearby water sources, including both tidal and
             freshwater from the Bayshore Mall restoration areas and
             freshwater from Maurer Marsh, are on private lands and currently
             not available. In addition, on-site groundwater resources are
             approximately five feet below grade. Potential flooding problems
             with the Bayshore Mall project, as well as untested success of
             the restoration projects (including this project), indicated that
             more information was necessary before obtaining the best,
             utilization of the surrounding areas. The relative costs
             associated with removal of large amounts of paving and fill, in
             comparison with costs associated with the rest of this project,
             also dictate delay of major enhancement efforts. As "Parcel 4",
             the adjacent coastal dependent industrial parcel is developed,
             wetland mitigation requirements could be partially fulfilled at
             this location. For these reasons, minimum excavation/grading is
             presently proposed within this area. The project will become
             fully planned as some of the above mentioned constraints are

                                             A-A

             removed. This should be undertaken as "Phase 2" for this
             project. (See Section 4.9)

             Other opportunities for providing additional tidal influx to
             Palco'Marsh included constructing a new or larger culvert under
             the railroad right-of-way. Major grading would be necessary in

             the Bay, as well as the Marsh to take advantage of any benefits.
             A drainage structure, at the northwest corner of the Palco Marsh,
             also would allow additional but limited opportunities for tidal
             and freshwater runoff influence in the Marsh. This had the
             potential of causing the storm drain system to back-up during
             peak storm flows. In addition, a more centralized location for
             tidal exchange seemed more appropriate for meeting the goals of
             this project. This drainage structure would be an option in the
             future if site conditions or management goals warranted. Another
             option was to keep the RR Marsh drainage separate from the Palco
             Marsh. Tidal influx is now partially blocked by the 36 inch
             sewer line that crosses the channel between the railroad
             right-of way and the maintenance dike. Tidal input would be
             increased if flow lines of the ditch were excavated below the sewer
             line. This option may be beneficial to the Bayshore Mall
             Restoration Project and should be further developed as part of
             Phase 2 of this project-

             Additional open water areas could be provided in the interior of
             the fresh/brackish marsh without use of heavy equipment. This
             would be accomplished by utilizing a technique, not common in
             Coastal California, but used extensively in the Mid-West and
             Northeast portions of the United States to open marsh areas for
             wildlife use. This involves placing small amounts of Ammonia
             Nitrate fertilizer in various locations and detonating it with an
             electric charge. This method could create several 20 x 20 foot
             freshwater pond "holes", which could have a life expectancy of
             10-15 years before infilling again. This is a low cost method
             which is less intrusive than heavy equipment use. State certifi-
             cation for use of explosives is required. This alternative was
             not further pursued though its application at this site seemed
           -appropriate. Additional research as to its applicability to this
             area should be pursued by an appropriate resource agency, and if
             feasible, applied to this site.

                 4.5 Proposed Enhancement Plan - Construction Aspects

             The Enhancement Plan has been designed to minimize construction
             impacts on non-involved areas of the Marsh. This included avoid-
             ing the use of heavy equipment in the middle of the marsh. Except
             for the excavation of the open-water area in the infilled fresh-
             water marsh and the central inlet channel, most of the proposed
             improvements can be completed from adjacent upland areas.

             Overall clean-up of the site should be completed and temporary
             access controls should be installed as soon as possible. Signs
             describing the future enhancements efforts should be installed at

                                            A -

     qJ

              the existing access points: Vigo and Del Norte Streets.
              Monitoring programs should begin baseline data collection prior
              to construction.

                        4.51 Palco Marsh Com2lex

              The tide gate at the Bay will be removed after the construction
              phase of the project. Until then, and just-prior to construction,
              the gate should be put into operating condition and left in place
              to temporarily eliminate tidal input during construction. The
              flapgate should be stored for temporarily reinstallment if required
              for maintenance purposes.

              Construction of the inverted siphon will involve placing two 18
              inch culverts under the sewer lines which are enclosed in the
              City maintenance dike. The flow line will be approximately at
              0.0 foot (City Datum). A weir box will be placed at both ends of
              the 18 inch pipes to allow manipulation of water levels. These
              boxes will be covered with a debris screen for public safety
              purposes. Since the flow line elevation in the culvert that
              brings in tidal input is at 3.7 foot, all areas in this structure
              and within the Marsh below 3.7 foot elevation will be inundated.

              The weirs will be adjustable from 3.0 to 7.0+ foot elevation,
              allowing a wide range of marsh management goals. Initially the
              weir should be set at 3.0 feet elevation. This allows the maxi-
              mum amount of both tidal input and run-off drainage.

              Channels will be constructed with flow lines beginning at about
              3.0 foot elevation in the marsh, one towards the east, 200 feet,
              and two others adjacent to the maintenance dike; one north for
              500 feet and one south to Vigo Street, 850 feet. Channels will
              be approximately 3 foot wide. Flow lines will gently slope from
              3.0 feet at the inlet to 4.5 feet at the channel ends. Sides
              will be sloped at 2:1. Smaller channels, two foot wide, one foot
              deep 14,0-4.5 foot elevation) will be hand dug in locations where
              several existing channels have filled with sediment, as indicated
              on on the Enhancement Plan Map.

              The hydraulic modeling, developed as part of the site analysis
              for this project, indicates that these improvements will increase
              both tidal fluctuation into the Marsh and run-off drainage from
              the Marsh. Figures 9 a, b, c, and d (pages 4-9, 4-10) depict
              both present and expected water level fluctuation during   a normal
              tidal cycle and during periods of storm run-off. Figure'9a shows
              a typical tidal fluctuation in the Bay overlaid with the existing
              muted tidal prism, as well as the tidal variation expected from
              the proposed improvements. As depicted, the Marsh will be sub-
              ject to a diurnal tidal cycle and in-phase with the tides occur-
              ring in the Bay. Maximum water levels will remain approximately
              where they currently exist. Minimum water levels will approach
              channel bottoms elevations. Table 6 compares tidal water eleva-
              tions, volume and inlet velocities for both present and proposed

                                              4-8

                                            NORMAL CONDITIONS, NO PRECIPITATION (A)

                                    7

                                                                                                                       -TIDAL PRISM IN BAY

                                    6--

                                                                                                                                       MARSH
                                                                                                                         IDAL PRISM IN
                                                                                                                        (PRESENT CONDITIONS)

                           C3                                                                                          -TIDAL PRISM IN MARSH
                                    5
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                                                                             4-9                 TIDAL PRISM / STORM RUNOFf
                                                                                                             Figure 9 (AaB)

                                      10 FOOT TIDAL SURGE, 10 AND 100 YEAR STORMS (C)

                                                          TIDAL FLUCTUATION IN SAY

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                                                                             ELEVATION
                                                                            Scale:   Horiz. I"TIO,
                                                                                     Vert. 1 ..2 5t
                                                                            City Datum                 ENHANCEMENT PLAN-
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                                                                         4-11                                    Figure 10

              conditions. Figure 9b represents the response of the marsh to a
              "two-year flood". As depi6ted, the present conditions depict an
              extended drainage time required (58 hours after the peak) before
              reaching normal water surface elevation. With the proposed
              improvements this time is reduced to 14 hours. Figure 9c depicts
              the response of the marsh to extreme flooding events for both
              present conditions and with proposed improvements.    Flood level
              water elevations will not be significantly increased and should
              be somewhat lower than depicted on the graphs; the higher levels
              shown represent a six hour precipitation event coinciding with a
              10 foot tidal surge. Proposed improvements will improve drainage
              under most flood conditions. Though peak water elevations will
              remain the same, run-off will be discharged from the site at a
              more expedient rate. Table 7 compares response of the marsh to
              the proposed improvements.

              Figure 9d depicts modeling results, which represented conditions
              occurring in February, 1986 (See Section 3.32). With the proposed
              improvements, water levels in the Marsh would respond by rising
              and falling after each precipitation event, drastically reducing
              the opportunity for water levels to build up and subsequently
              flood adjacent properties.

              A 1.5 acre open water area will be created in the southeast
              corner of the Marsh which will replace dominant cattail vegetated
              areas. The pond will be "L" shaped, approximately 100 feet across
              with several island areas. Bottom elevations will be at 0.0 feet
              sloping upwards to existing elevations of 6.0 feet. An eight to
              ten foot wide dike, at approximately 7.0 foot elevation (6-12
              inches high) will be placed around the north, west and south
              perimeter. Natural overflow will occur over the dike. An
              adjustable weir will be installed at the western end of the open
              water area to allow adjustable pond heights between 3 and 7 feet.
              This design incorporates measures that will lessen the current
              problem of backflooding into the Mauer Marsh and improve the
              draingage during flood conditions.

              Excessively wet conditions in the open water area may require
              temporary fill to be placed in the construction area and utilized
              as a road to transport materials from the area. Fill materials
              will come from the paved area. This fill would be removed as
              surrounding excavation is completed. Several islands will be
              left intact as resting islands for wildlife. Fill that is
              removed may be utilized for the raised viewing platform on the
              Del Norte Street Peninsula.

              RevegetatLion within the salt marsh will be limited, for the most
              part, tc along the upper edges of the newly constructed channels.
              This will involve planting salvaged pickleweed and salt grass
              from excavated areas. The interior areas of the salt marsh, which
              have experienced die-back of vegetation, may take a year or two to
              have conditions conducive to revegetation. Natural revegetation
              should be adequate once healthy conditions return.

                                             4-13

             Salt marsh areas will be allowed to develop naturally under the
             influence of tidal circulation in the site and natural seed
             dispersal from the surrounding areas. Natural development of
             wetland vegetation should be favored by slow water currents and
             nearness of seed sources. Target species include pickleweed,
             saltgrass, jaumea and arrow grass. Water level management (pre-
             soaking of seeds) is an option that can be undertaken by, the
             managing entity once the project is underway and specific infor-
             mation is available. This will be done by periodic adjustment of
             the weir structure at the inlet channel. The open water area
             will be influenced by surrounding cattail and common rush vegeta-
             tion surrounding the pond. Steep sloping sides will prevent
             infilling by cattails, preserving the open water aspect. Sources
             of hydracotyl and other submergent vegetation exist in the
             remnant pond on the project site.

             Plantings of willow and alder will occur at various locations for
             screening and buffering adjacent land uses. Solid plantings will
             occur along Felt and Del Norte Streets. Periodic clumps will be
             planted along the north side of Vigo Street, the east side of the
             maintenance dike, and in the picnic area on the Del Norte Street
             Peninsula.

             Cuttings will consist of three sizes depending on soil moisture
             conditions: 1/2", 1" and 2" diameters, approximately 18 inches
             long, and should be planted at a density of approximately 2,000
             per acre, spaced every 4 feet. Red alders should be inter-
             dispersed in the plantings to provide variation in canopy
             height, particularly near public access areas.

             The four exotic species of concern should be removed as neces-
             sary and monitored yearly. This will prohibit re-establishment.
             The extent of scotch and/or french broom is limited and can
             easily be removed by hand grubbing plants. Care should be taken
             to remove this plant with the roots prior to seed development.
             Removal during flowering season will aid in identification and
             location of plant.

             The removal of pampas grass presents a more difficult problem;
             but if done with care, will cut down on the intensity of growth
             now occurring. The majority of the pampas grass occurs along the
             maintenance dike, the railroad right-of-way, the northwest sector
             of Palco Marsh, and/or the Del Norte Street Peninsula. Seed
             stalks should be removed prior to major disturbance of the plant.
             are should be taken not to discharge the wind dispersed seeds.
             The majority of the leaves should be cut down to ground level and
             C

             rock salt should be poured onto the remaining clump.

             Specimens located on the peninsula at the marsh edge and along
             the side of the maintenance dike can be removed by a backhoe,
             removing the rootball intact. The specimens located along the
             top of the maintenance dike may be scraped or dug out with special
             care not to disturb the underlying water or sewer lines. The
             specimens scraped, as well as those located on the railroad
             right-of-way will probably require additional hand removal of

                                           4-14

           plants. All holes should be examined for evidence of complete
           removal of the rootball and subsequently filled with the appro-
           priate materials (clean, upland soil/gravel).

           Removal of the common reed specimens present also requires
           special care. Though specimens are, for the most part, acces-
           sible by backhoe, special care is necessary to assure complete
           removal. Seed stems should be removed prior to disturbance and
           disposed off-site with care not to disperse seeds (burning on-
           site is an option). Specimens should be cut down and treated
           with rock salt and later, where appropriate, removed by backhoe.
           Visual checking and hand clearing should follow. Surrounding
           soils, which may contain dormant seeds, should also be scraped
           and removed off-site. Since this plant propagates from rhizomes,
           special care to remove all roots is necessary. Holes left from
           removal of plants, if not part of designed excavation plans,
           should be filled so as not to provide ponding for mosquito repro-
           duction. Since this plant seems to be limited to stressed
           brackish marsh habitats, increasing tidal actions should elimi-
           nate this concern.

           Gravel fill will be placed on top of the maintenance dike to a
           minimum elevation of 8.5 feet and will serve as the main pede-
           strian access to the site. Public access will be available from
           the Vigo Street entrance, along the paved road and unto the
           gravelled surface trail to Del Norte Street. Each end of the
           maintenance dike will have a walk-around entrance gate that
           allows pedestrian access, as well as a locked gate for main-
           tenance purposes. Project identification and usage signs will be
           posted at each entrance. Eight benches will be placed at various
           locations between the Vigo Street entrance and Del Norte Street.

                4.52 Paved Pa Shed Area / Railroad Marsh

           The drying sheds should be sold as surplus property or put out to
           bid for salvage/removal. other debris, left from use of the mill
           site, including remnants of a burned shed, fencing and the
           railroad spur should also be removed.

           Directly at the end of Vigo Street a 100 x 200 foot paved area
           will be reserved for parking. A 40 foot wide strip of paving and
           fill will be removed from the south and west sides of the parking
           area to construct a barrier for vehicular access onto the remain-
           ing paved areas. This barrier will consist of a combination of
           berms, ditches and willow plantings. If poles were available
           from the salvaged drying sheds, these could be used as either
           bumper logs or as fence posts for an additional access barrier.
           A locked gate will allow access to the remaining paved area for
           future enhancement and maintenance purposes. Vehicular access
           from Mill Street to the paved area will be discouraged by a
           combination of fencing, berms and plantings.

           The RR Marsh will be excavated and initially used as a settling
           basin for drainage from dredge spoils. The drainage ditch that

                                          4-15

              currently exists between the railroad right-of-way and the
              maintenance dike will be cleared of debris and graded to 4.1 foot
              elevation for a distance of 400 feet. Two 12 inch culverts will
              be placed under the maintenance dike just south of where the
              sewer line crosses the ditch. New channels in the RR Marsh will
              be excavated to 4.0 foot elevation, the railroad spur will be
              graded from 5.5 foot to 8.0 foot elevation. A channel will
              extend from the RR Marsh south adjacent to the railroad r.ight-of-
              way 300 feet. This would limit vehicular access to or from the
              railroad right-of-way.

              The unused, paved area could serve as a temporary area for
              drying and storing channel dredgings from this project. This will
              be particularly important for handling the saturated, organic
              soils removed from the freshwater open water pond. The area
              would be bermed to direct drainage towards the RR Marsh.

                        4.53 West of Railroad Tracks

              Improvements west of the railroad right-of-way are limited to
              that portion located on or adjacent to the Del Norte Street
              Peninsula. A twenty spaced paved parking area will be provided
              off the end of Del Norte Street to be used as access to this
              project, as well as the Del Norte Street pier, if and when recon-
              struction of that project occurs. Sidewalks will extend to the
              end of Del Norte Street. An information kiosk will provide edu-
              cational information of the project site. Curbing and fencing
              will limit vehicular access to the paved parking and street. A
              half acre flat area will be designated as a picnic/play area just
              south of the parking area and will be planted with native trees
              and shrubs around its perimeter. Typical species will include
              wax myrtle, ceanothus, shore pine, willows and alders. Restrooms
              are not being proposed as part of this project but allowances
              have been made to locate them adjacent to the parking area. An
              area directly east of the parking area will be reserved for
              future parking needs. Non-saline soils and fill removed from the
              paved drying shed area will be deposited towards the southern end
              of the peninsula to form a 4 foot high viewing area.

              The existing drainage channel/slough between the peninsula and
              the railroad right-of-way tends to fill in, and needs periodic
              dredging. Bank slumping also occurs along both sides of the
              channel. According to City staff, maintenance of the channel
              occurs approximately every ten years. Dredgings from the channel.
              have periodically been stored in an area adjacent to Del Norte
              Street and removed when dry.

              A maintenance road will be constructed along the channel and
              connect to the existing gravelled roadway-This will be used as a
              trail for pedestrian use. A four foot wide trail will extend
              onto the viewing area mound. A steep bank, at the southern end of
              the viewing mound, in addition to blackberry or willow plantings,
              should discourage access into the fragile, narrow salt marsh
              bluffs at the southern end of the peninsula.

                                              4-16

                 4.6 Operation/Maintenance

            Facilities required for safe and effective operation and mainten-
            ance of the wetland site should be monitored and repaired as
            needed. Facilities to be maintained include the inverted
            siphon/water exchange improvements. This will include periodic
            sediment removal from both sides of the culvert and potential
            flushing of pipes. This should be inspected and corrected as
            needed previous to each rainy season and after each substantial
            storm event. Weir adjustment may also be periodically altered to
            obtain a preferred management goal. Other facilities to be main-
            tained include the maintenance road, Vigo Street, parking areas,
            fencing, gates, signs, and culverts. Collection of litter and
            trash will be periodically needed, as well as street sweeping the
            parking areas and brushing the road sides.

                                           4-17

                  4.7 Monitoring

             Monitoring the site for hydraulics, vegetation, invertebrates,
             wildlife and mosquitoes will be necessary for several years after
             construction is completed to ensure that enhancement goals are
             satisfied and to develop a management plan for the area.

             Monitoring should started prior to the construction phase to
             develop baseline conditions. This will be necessary to determine
             changes as a result of this project. In addition, yearly reports
             should be compiled to compare findings in the various mentioned
             disciplines described below

             Hydraulics

                  1.  Monitor water levels in the marsh over a complete tidal
                      cycle quarterly, and at least once during or after a two
                      year storm event to compare with hydraulic modeling
                      results. Observe flow patterns and velocities, identify
                      restrictions or flow problems and adjust weirs to
                      decrease/increase velocities.
                  2.  Utilize results to fine tune the system to meet
                      management goals.

             Anticipated Schedule: 10 person-days per year, 2 years

             Vegetation

                  1.  Prior to construction, establish representative test
                      plots in existing stressed and healthy salt marsh areas.
                      Inventory for species presence and density prior to
                      improvements.    Recheck and evaluate once a year, for
                      years 1, 2 and 4. If significant progress does not occur
                      after year 4, make adjustments consistent with wildlife
                      use analysis.
                  2.  Yearly obtain and review aerial photographs of the
                      project site, as well as adjacent wetlands .

             Anticipated Schedule: 10-15 person-days per year, 4 years

             Invertebrates

                  1.  Prior to construction, establish representative test
                      plots in existing stressed and healthy salt marsh areas.
                      Inventory for species presence and abundance prfor to
                      improvements. Recheck and evaluate after year 1, 2 and 4.
                      Correlate with wildlife use of the site, particularly during
                      fall migration of shorebirds.
                  2.  Locate and monitor development of rare species habitat
                      range.

             Anticipated schedule: 5 person-days per year, 4 years

                                             4-18

              Wildlife

                    1. Starting in the fall of 1987, census the area seasonally
                       for 3 years, at different times of day and tidal cycle.
                       Correlate information with local birdwatcbers for changes
                       in wildlife use. Identify available food source development.

              Anticipated schedule: 10-15 person-days per year, 3 years

              M's quitoes

                   1. Review recommendations from County Health Department's
                       monitoring of site to identify problem areas. incorporate
                       needs into management goals to minimize problem.

                                             A-1 9

                   4.8 Permit Requirements

             This  enhancement project will require several permits from local,
             State and Federal agencies. Permit types and approximate
             processing time requirements are listed below:

                   1.  City of Eureka - Approval of Development Plan,
                       processing of CEQA document. Processing time: @30-45 days

                   2.  Humboldt Bay Harbor, Recreation and Conservation
                       District - permit for all construction in areas below
                       MHHW. Processing time: 45 days

                   3.  California Coastal Commission - Coastal Development
                       Permit for construction within CCC permit jurisdiction
                       Subject to review and concurrence from Department of
                       Fish and Game. Processing time: 90 days

                   4.  U.S. Army Corps of Engineers - Permit for construction
                       in all wetland and slough areas pursuant to Section 404
                       of the Clean Water Act and Section 10 of the Rivers and
                       Harbors Act. Subject to review by U.S. Fish and
                       Wildlife Service, California Department of Fish and
                       Game, Regional Water Quality Control Board and others.
                       Processing time: 90 days

                   5.  California Department of Fish and Game - 1603 Permit for
                       work in wetland and sloughs. Processing time: 30 days

                   6.  Eureka Southern Railroad - Permit required to construct
                       any work within the railroad right-of-way.
                       Processing time: less than 30 days

             Permitting requirements of the resource agencies are interlocking
             and interdependent as to timing. For example, the Coastal
             Commission will not accept an application until the Harbor
             District has acted, and the Corps of Engineers will not process
             an application until the Coastal Commission has accepted an
             application. Permitting processes will probably require a total
             of approximately six months to complete.

             This enhancement project, within the city limits of Eureka,
             constitutes a "development" project and, therefore, is subject to
             similar requirements of other projects. The City requires that
             any project which is the "final development" of a parcel will be
             improved to current standards, for, amongst other things, street
             improvements. The Palco Marsh project site fronts three7sections
             of public street; Del Norte Street, Felt Street and Broadway
             Avenue. Discussion with City officials indicates that six foot
             sidewalks will be required as part of the "development" of this
             project. This will require placing some fill adjacent to the
             Marsh edges.

                                              4-20

                           4.9 Future Enhancement Work, "Phase TwoO

               Removal of the majority of paving and fill in the drying shed
               area will occur at a later time, probably in conjunction with
               development of 'Parcel 4' as mitigation. An Enhancement Plan
               should be developed of this area which will include the
               surrounding restoration and enhancement areas. Results from
               monitoring and fine tuning the systems, and any overall required
               improvements, should be included in conjunction with future
               enhancement work.

               Several alternatives were considered for the paved area that
               involved grading for varying degrees of salt/brackish or
               freshwater marsh habitats, depending on the source of water
               utilized. Several nearby water sources, including both tidal and
               freshwater from Maurer Marsh, are on private lands and currently
               not available. -In addition, on-site groundwater resources are
               approximately five feet below grade. Potential flooding problems
               with the Bayshore Mall project, as well as untested success of
               the restoration projects (including this project), indicated that
               more information was necessary before obtaining the best
               utilization of the surrounding areas.

               One alternative would involve removing all asphalt and fill from
               the project site, grading slopes towards a central channel and
               providin g a large open water area, which would overflow into the
               Palco Marsh (Figure 11). Estimated construction costs (1987)
               associated with removal of materials from the remaining 5 acre
               site, considering the above enhancement alternative, are listed
               below.

                   Removal of asphalt             220,000 sf              $22,000

                   Excavate to 71 elevation        16,300 cy             $130,000

                   Excavate a 20 square foot
                   channel, 700 feet long             520 cy              $4,000

                   Excavate one acre pond,
                   5 foot deep                      8,000 cy              $64,000

                   Adjustable weir structures           2 ea              $4,000

                   Revegetation                     Lump Sum              $8,000

                   Monitoring                                             $ 6,000

                                                    TOTAL            $238,000

                                               4-21

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                                                                                                                                                                           ENHANCEMENT PLAN
                                                                                                                                                           CONCEPTUAL PHASE TWO
                                                                                                                          4-22                                                                   Figure 11

              City of Eureka, Department of Public Works, Miscellaneous
                    Elevation Datum Relationship.

              City of Eureka, Department of Public Works, Storm drainage maps
                    and information.

              Everson, R.E., Geology and Groundwater Features of the Eureka
                    Area Humboldt County, California. Geologic-@Tl '@-urvey water
                    Supply Paper 1470. 1959.

              Federal Emergency Management Agency, Flood Insurance Study, City
                    of Eureka, CA, Humboldt County. Revised Map June 17, 1986.

              Gerstenberg, R.H., A Study of Shorebirds (Charadrii) in Humboldt
                    Bay, CA 1968 to 1969. Masters Thesis/Humboldt State
                    College, June 19 .

              Humboldt Bay Harbor, Recreation and Conservation District.
                    Humboldt Bay Master Plan, July, 1975.

              Josselyn, M. 1983. The ecology of San Francisco Bay tidal
                    marshes: a community profile. U.S. Fish and Wildlife
                    Service, Division of Biological Services, Washington, D.       C.
                    FWS/OBS-83/23. 102 pp.

              Josselyn, Michael, 1982. Wetland Restoration and Enhancement         in
                    California California Sea Grant Report No.. T-CSGCP-007
              Koplin, J.R., Franklin, A., and G. Newton. 1984. Elk River
                    Wildlife Monitoring Project, Final Report. Unpublished
                    summary report available from the City of Eureka.

              LSA   (L. Seeman and Associates).      1985.   Wetland restoration plan,
                    Bayshore Mall. Unpublished final report available from the
                    City of Eureka.

              LSA,  1986. Eureka LCP mitigation bank wetland restoration plan.
                    Unpublished report available from the City of Eureka.

              Mason, H. 1957. A flora of the marshes of California.
                    University of California Press, Berkeley.

              Monroe, G. 1973. The natural resources of Humboldt Bay.
                    Unpublished report available from the Department of Fish and
                    Game, Eureka.

              McKee, M., A Preliminary Assessment of Flood Control Alternatives
                    in the Bicol River and Estuary, Philippines, U.S. Agency for
                    International Development, 1983.

              Nestler, J. 1977. Interstitial salinity as a cause of ecophemic
                    variation in Spartina alterniflora. and Spartina cynocuroides
                    in Georgia coastal marshes. Estuarine and Coastal Marine
                    Science 5:707-714.

                                                R-2

              Newton, G. 1984. Vegetation mapping of proposed wetland
                   mitigation sites on Humboldt Bay. Unpublished report
                   available from Humboldt County.

              Newton, G. 1985a. Proposed wetland mitigation sites: Belcher,
                   Ford, and Lambert: Botanical Survey. Unpublished report
                   available from Humboldt County.

              Newton, G. 1985b. Botanical review and recommendations for the
                   second and third slough sewer line project. Unpubdished
     4             report available from the City of Eureka.

              Newton, G. 1986. Botanical review and recommendations for the
                   Palco Marsh Enahncement Plan. Unpublished report available
                   from the City of Eureka.

              Parrondo, R.T., J.C. Gosselink, C.S. Hopkinson. 1978. Effects
                   of salinity and drainage on the growth of three salt marsh
                   grasses. Botanical Gazette 139:102-107.

              Philip Williams & Associates, Design of Bayside Mall Marsh
                   Restoration Project, 1986.

              Pinder, G.F. and W.G. Gray, Finite Element Simulation in Surface
                   and Subsurface Hydrology, Academic Press, New York, 1977.

              Rogers, J.D. 1981. Net Primary Productivity of Spartina
                   foliosa, Salicornia virginica, and Distichlis spicata in
                   Salt marshes at Humboldt Bay, California. Unpublished
                   master's thesis, Humboldt State University, Arcata, CA.

              Shapiro and Associates, 1980. Humboldt Bay Wetland Review and
                   Bayland Analysis. Prepared by Shapiro and Associates for
                   the U.S. Army Corps of Engineers, San Francisco District.
                   August, 1980.

              Smart, R.M., and J. W. Barko. 1980. Nitrogen nutrition and
                   salinity tolerance of Distichlis spicata and Spartina
                   alterniflora. Ecology 61:630-638.

              TerraScan. 1979. Marsh Enhancement Plan and Draft EIR Phase II
                   - Arcata Marsh Enhancement Project. Prepared for California
                   Eo-astal conservancy and City of Arcata.

              United States Department of Commerce, NOAA, Tidal Bench Marks,
              Bucksport, Humboldt Bay, 1981, CA-941-8778.

              nited States Department of Commerce, NOAA. Climatological Data
                   of California, Environmental Data Services. 1986.
              U

              United States Fish and Wildlife Service.       1979.    Classification
                   of wetlands and deepwater habitats of the United States.
                   U.S. Fish and Wildlife Service, Biological Services Program,
                   Washington, D.C. FWS/OBS-79/31

                                               R-3

             Willis, R. and McKee, M. 1985. Hydrologic anaylisis for the
                 Palco Marsh Enhancement Plan.

             Zedler, J.B. 1982. The ecology of southern California coastal
                 salt marshes: a community profile. U.S. Fish and Wildlife
                 Service, Biological Services Program, Washington, D.C.
                 FWS/OBS-81/54. 100 pp.

             Zedler, J.B., 1984. Salt Marsh Restoration, A Guidebook for
                 Southern California.   alifornia Sea Grant Report No. T-
                 CSGCP-009.

                                           R-4

                                                              APPENDIX A
                                                  Some Notes on Circulation and
                                                      Sediment in Palco Marsh

                       1.  Circulation and Hydraulic Conveyance

                           Circulation and the response of the marsh to tidal fluctuations will be greatly improved
                           from present conditions by modifications of the marsh inlet and widening and
                           deepening of channels within the marsh. Circulation will be most improved if larger
                           channels (approximating the original marsh channels in size and cross sectional area)
                           can be constructed to connect the proposed marsh inlet weir to the historic channels in
                           the north and south marshes. It is important that the flow line for these channels be
                           lowered to the three- to four-foot level. In addition to improving marsh circulation,
                           these channels would (a) be less likely to choke with bottom and emergent vegetation
                           or slump or experience bank failure (which would decrease channel conveyance and,
                           in time, cause decreased flows within the marsh), and (b) limit public access to the
                           marsh area and thereby provide a measure of site security. In the long term, the size of
                           these channels will be key to preservation of improved marsh hydraulics and lowered
                           associated maintenance costs.

                      2.   Potential for Scour and Deposition of Sediment

                           By increasing the conveyance of the channels within the marsh, much higher flow
                           rates will be achieved but, because of the larger channel cross sectional areas,
                           maximum water velocities will remain low, probably smaller than 1 foot/sec for the
                           typical tidal cycle. Throughout most of the tidal cycle, velocities will be much lower
                           than this. This implies a potential for sediment deposition, and the aggradation of the
                           present marsh channels is evidence of this. However, the proposed channels would
                           be at a lower elevation than the present flow line, as would be the inlet/outlet. This
                           might ensure that the present high bottom elevations would not return, but might also
                           invite scour.

                           The prediction of deposition and scour is not an exact science. For example, the
                           Bureau of Reclamation recommends that, in designing earth-lined or unlined canals,
                           several tests on soil particle size, plasticity, shear strength, and tractive force be made.
                           From these data, the resistance to scour can be theoretically estimated, but even these
                           sophisticated descriptions of scour potential must be evaluated on the basis of
                           experience for the probable effects of cohesion, which is still beyond the capability of
                           sediment theory to predict.

                           For the proposed conditions in the Palco marsh, a potential control mechanism for
                           both circulation and sediment deposition/scour is the weir inletloutlet gate. By
                           lowering the elevation of the gate, higher channel velocities will be achieved in the
                           marsh, thereby implying better circulation and possible scour of channels that might
                           have been aggrading at a higher gate setting. Conversely, a higher gate setting will
                           lower the marsh channel velocities and reduce the potential for scour or increase the
                           possibility for deposition. The point of this is that the flow control mechanism that is
                           proposed for the marsh might also act, to a certain extent, as a device for regulafing. the
                           behavior of sediment in the marsh. The proper settings of the gate to achieve desired
                           circulation and sediment control goals will only be found by experimentation after the
                           gate is installed.

                                                                     A-1

                                        APPENDIX B

                                  VEGETATION DESCRIPTIONS

             The vegetation of the site is described in the following
             discussion. The delineation of each vegetation type (or plant
             assemblage) is based on species composition, quantitative
             variations, and structure.

                                        Salt Marsh -- SM

             The salt marshes on the site are located in a narrow band west of
            .the railroad tracks and in a broad area east of the tracks. The
             salt marshes west of the tracks contain the usual diversity of
             vascular plants typical of salt marshes around Humboldt Bay. In
             this narrow strip of marsh, the three dominant salt marsh
             species.. pickleweed (Salicornia virginica), cordgrass (Spartina
             densiflora), and salt grass (Distichlis spicata) occur together
             in varying amounts. Occasional throughout-these marshes are sea
             lavender (Limonium californicum var. californicum), jaumea
             (Jaumea carnosa), and arrow grass (Triglochin spp.). The rare
             Humboldt Bay gumplant is found along the edges of this marsh and
             the salt marsh snail (Ovatella myosotis) is common in this
             location.

             The salt marshes and extensive mud flats east of the tracks are
             degraded and lack much of the diversity common in healthy salt
             marshes on Humboldt Bay. With the exception of the three main
             salt marsh species -- pickleweed, cordgrass, and salt grass --
             none of the other salt marsh species occur in this area. The
             ?nly location that contains a gumplant and a modest population of
             Jaumea is a small portion of pickleweed marsh adjacent to the
             inlet. Marine infauna are only found near the inlet and the
             normally ubiquitous salt marsh snail is absent from these
             marshes.

             Orache (Atriplex patula) and brass buttons (Cotula corono ifolia)
             are common in many of the areas east of the tracks, becoming
             dominant in small areas. These species are typically found in
             areas that are disturbed or severely stressed. Most likely, the
             areas more removed from the tidal inlet experience oxygen
             starvation and hypersalinity due to evaporation during the summer
             months.

             One area east of the tracks seems to be eroding at an accelerated
             rate. Aerial photos show that the majority of the erosion has
             occurred since 1981, with significant differences betwedn 1983
             and 1986. Tufts of salt grass from which the substrate has been
             eroded still persist in this area.

             Since the health of the existing salt marsh east of the tracks is
             one of the main concerns of the enhancement project, the
             vegetation was mapped in detail. Other marshes on Humboldt Bay

                                             B-1

             located at similar elevations are usually dominated by pickleweed
             and jaumea. The following vegetation descriptions and codes
             relate to the vegetation map of the site.

                          SM      cordgrass/pickleweed/salt grass
                        (Spartina densiflora/Salicornia virginica/
                                    Dl-stichliE spicata)

             The three salt marsh species do not form distinct zones-within
             these marshes because the marsh has formed behind a steep bank
             and lacks a gradual interface with the bay and with tidal
             inundation, except during the highest tides. Generally, the
             species occur either in equal amounts, or with pickleweed
             dominating up to 70% of the vegetative cover. This salt marsh is
             only found west of the tracks. In addition to the dominant
             species, other species such as sea lavender (Limonium
             californicum var. californicum), jaumea (jaumea carnosa), arrow
             grass (Triglochin spp.), Humboldt Bay gumplant (Grindelia stricta
             ssp. blakei), sea plantain (Plantago maritima ssp. juncoides),
             and mud-spurry (Spergularia marina) can be found. These
             additional species are generally lacking east of the tracks. The
             overall height of the vegetation varies from 0.66 feet (20 cm) in
             a pickleweed dominated area to 2.3 feet (70 cm) in a cordgrass
             dominated area; cover is usually 100%.

                                   SM 2 -- pickleweed
                                  (Sallcornia virginica)

             These marshes, which are dominated by pickleweed, are found east
             of the tracks in areas directly affected by tidal inundation.
             The pickleweed occurs in monotypic stands or as the dominant with
             salt grass (Distichlis spicata) and orache (Atriplex patula).
             Salt grass is usually less than 10% of the cover and oracbe can
             '
             be as high as 50% of the cover (occasionally more). The height
             of the vegetation averages 0.98 feet (30 cm); cover is 100%.

                                   SM3 -- salt grass
                                   (Distichlis spicata)

             The salt grass marshes are at the upper limits of the salt
             marshes and intergrade with the various brackish marshes and
             upland grasslands. in this vegetation type salt grass is the
             dominant plant; pickleweed is present but only in scattered
             patches. Orache is present usually with less than 25% cover, and
             brass buttons and water foxtail are occasionally present. The
             height of these areas averages 0.82 feet (25 cm); cover is 100%.

                                SM4 -- salt grass/barley
                             (Distichlis spicata/Hordeum sp.)

             This vegetation type is very similar to the previous type. Salt
             grass is the dominate species. The main distingui,shing feature
             is the addition of various grass species. These grass species
             are present in small numbers, but are consistently found
             intermixed with the salt grass: water foxtail (Alopecurus

                                           B-2

             genticulatus), ryegrass (Lolium perenne), and bromegrass (Bromus
             mollis). This assemblage of plants is usually located near the
             upper edges of the salt marsh near the upland grasslands. Height
             is 1.15 feet (35 cm); cover is 100%.

                           SKS -- pickleweed/salt grass/orache
                         (Salicornia virginica/Distichlis.spicata/
                                     Atriplex patula)

             The three salt marsh species --pickleweed, salt grass, and orache
                occur in equal amounts. This type of marsh is found east of
             the tracks at the middle elevations, above the pickleweed line
             but below the salt grass areas. The height varies from 0.46-0.92
             feet (14-28 cm); cover is 100%.

                            SK6 -- salt grass/tufted hairgrass
                        (Distichlis spicata/Deschampsia caespitosa)

             This combination of salt grass and tufted hairgrass (Deschampsia
             caespitosa) is found only west of the railroad tracks. A few
             species common to dune habitats are also found in these areas:
             beach bur (Ambrosia chamissonis), dune tansy '(Tanacetum
             douglasii), Tracy's salt rush (Juncus lesueurii var. tracyi), and
             sand sedge (Carex pansa). This combination of plants is located
             at the upper edge of the tidal marshes in areas underlain with
             sand dune soils. The height of the vegetation varies from 0.82
             feet (25 cm) in the absence of tufted hairgrass to 2.95 feet (90
             cm) in the presence of the hairgrass; cover is 100%.
                             SK,,;- salt grass/water foxtail
                       (Distich    spi ata/Alopecurus genticulatus)

             Salt grass and water foxtail occur in approximately equal amounts
             with up to 10% of salt rush (Juncus lesueurii var. lesueurii),
             orache (Atriplex patula), and pacific silverweed (Potentilla
             egedii ssp. grandis).   This vegetation type is found at the
             upper reaches of the salt marshes which border on brackish marsh.
             The height of the vegetation varies but is usually 0.82 feet (25
             cm); cover is 100%.

                                    Brackish Marshes -- BM

             Brackish marshes form at the interface between the salt marshes
             and the freshwater marshes. Therefore, the range of salinities
             found in these marshes is highly variable in space and time. The
             species composition slowly changes as one moves from the areas
             near the salt marshes to the areas near the willow swamps or
             riparian woodlands. Three species of plants which are common
             throughout these brackish marshes are salt rush (Juncus lesueurii
             var. lesueurii, pacific silverweed (Potentilla egidii ssp.
             grandis), and water parsley (Oenanthe sarmentosa).

             In general, the brackish marshes found on the site are typical of
             other such marshes around Humboldt Bay. Two types of marshes

                                            B-3

             located on the site that are uncommon around Humboldt Bay are the
             pacific rush (Juncus effusus var. pacificus) and the common reed
             (Phragmites communis var. berlandieri) stands. The pacific rush
             marsh represents a unique resource; the common reed marsh
             represents a threat to Humboldt Bay marshes. Though none of the
             brackish marshes, or species therein, are rare, the uniqueness of
             this site lies in the quantity and diversity of the marshes
             represented. Within these parcels, most of the common types of
             marshes can be found.

             The brackish marshes on the site are separated by species
               position and structure. Structure of plant associations is
             believed to be very important in ascertaining wildlife uses of
             com

             the habitat. The brackish marshes vary from very short areas
             dominated by grass species to the tall stands of slough sedge
             (Carex obnupta).

                            BM, -- salt grass/water foxtail/
                                       pacific silverweed
                       (Distichlis spicata/Alopecurus genticulatus/
                             'Potentilla egedii ssp. grandis)

             This brackish marsh is found on the upper edges of the salt
             marshes and is influenced by tidal waters. Salt grass, water
             foxtail, and pacific silverweed are found in approximately equal
             amounts with scattered patches of one or more of the following:
             orache (Atriplex 2atula), spikerush (Eleocharis'marostachya), and
             brass buttons (Cotula coronopifolia). The height of this marsh
             averages 1.48 feet (45 cm); cover is 100%.

                      BM2 -_ water foxtail/salt rush/velvet grass
                      (Alopecurus genticulatus/juncus lesueurii var.
                                lesueuriiUH-ok-us lanatus)

             The combination of water foxtail, salt rush and velvet grass
             (Holcus lanatus) is found in one area located near the salt
             marshes and near a freshwater inlet. This type is very similar
             to the previous type with the addition of grass species, most
             notably velvet grass and bent grass (Agrostis sp.). Salt grass
             and orache are present in this area but with less overall
             coverage. The height of the vegetation is 2.3 feet (70 cm);
             cover is 100%.

                             BM3 -- three-corner/salt grass
                          (Scirpus americanus/Distichlis spicata)

             Three-corner (Scirpus americanus) occurs in areas that U.@Ually
             have standing water throughout the year. Three-corner mixes with
             the salt grass in one area at the upper margin of the salt marsh,
             directly off the inlet to the marsh. Very few other species are
             associated with this type. Occasionally pacific silverweed
             (Potentilla egedii ssp. grandis) and water foxtail (Alopecurus
             genticulatus) are included. The height of this type is 2.79 feet
             (85 cm); cover averages 85%.

                                            BI-4

                          BN4      salt rush/pacific silverweed/
                                      common rush/water parsley
                        (Juncus lesueurii var. lesueurii/Potentilla
                           egedii ssp. grandis/Juncus effusus
                           var. brunneuMin-anthe sarmentosa)

             This vegetation type is highly variable. It changes dominant
             species gradually, from the mudflats to the riparian areas (or
             willow swamps). This vegetation type covers the majority of the
             brackish marshes east of the salt marshes. The plant assemblage
             contains a diverse mixture of species dominated by salt rush
             (Juncus lesueurii var. lesueurii) with pacific silverweed
             (Potentilla egedii ssp. grandis), some salt grass (Distichlis
             spicata), water parsley (Oenanthe sarmentosa), small-seeded
             bulrush (Scirpus microcarpus), willow herb (Epilobium watsonii
             var. franciscanum), fireweed (Erechities prenanthoides), curly
             dock (Rumex crispus), and aster (Aster chilensis).

             The dominant rush species changes from the salt rush to common
             rush (Juncus effusus var. brunneus) as one approaches the willows
             but the species composition remains very similar with two notable
             additions. Speedwell (Veronica scutellata) and monkeyflower
             (Mimulus guttatus ssp. litoralis) are more common on the eastern
             p-ortion of these brackish to freshwater marshes, though still
             only present in very low amounts. These two species are much
             less salt tolerant and require very wet areas. The height of the
             vegetation is variable at this time of year due to the fact that
             the salt rush is lying down rather than standing erect; therefore
             a range, from 2.79-3.28 feet (85 to 100 cm), gives a better
             indication of the structure of the type; cover is 100%.

                                   BK4 -- pacific rush
                              (Juncus effusus var. pacificus)

             Small, 9.8 feet diameter (3 meters), areas occur within the BM4
             brackish marsh type that are nearly monotypic stands of a tall
             variety of the common rush known as pacific rush (Juncus effusus
             var. 2acificus). The species is not common around Humboldt Bay.
             The height of these areas is approximately 5.23 feet (160 cm);
             cover is 90%. These small patches are denoted as BM4a* The
             delineation is mainly due to structure.

                           B145     slough sedge/water parsley
                            Warex obnupta/Oenanthe sarmentosa)

             This type of brackish marsh is very common around Humboldt Bay in
             areas that are seasonally to perennially wet. On Palco Marsh,
             slough sedge (Carex obnupta) attains a height of 5.58 fe@et (170
             cm). The salinity tolerances of this species are very wide; it
             can be found from the upper edges of salt marshes to the
             freshwater marshes and willow swamps. The stands on the site
             are nearly monotypic, but they can contain small amounts of water
             parsley (Oenanthe sarmentosa) and pacific silverweed (Potentilla
             egedii ssp. grandis). Cover is 100%.

                                            B-5

                                   ----------

                             BM5a -_ Carex lyngbyei/Oenanthe

            Essentially, this brackish marsh is a sub-set of the previous
            marsh. It is separated out due to the difference in its
            structure. This marsh contains a sedge species which most
            closely resembles Lygnbye's sedge (Carex lyngbyei), but which
            also contains characteristics similar to slough sedge (Carex
            obnupta). The taxonomic uncertainties associated with this
            species have been observed elsewhere on Humboldt Bay.

            The height of this marsh is 2.95 feet (90 cm); cover averages
            98%. Interspersed throughout the culms are the companion species
            of pacific silverweed and water parsley, a little more common in
            this type than in the previous type.

                                BM6 -- saltmarsh bulrush
                                   (Scirpus robustus)

             The saltmarsh bulrush (Scirpus robustus) stands on the site are
            typical of Humboldt Bay    nds, which occur in brackish marshes
            and in sloughs and channels at the upper reaches of salt marshes.
            These monotypic stands require persistent water; other species
            are rarely found there. The height of these stands was found to
            be 2.30 feet (70 cm). This figure is heavily biased by the time
            of year; the majority of the culms are broken and dead. Cover
            averages 70%.

                                   BM7     common reed
                         (Phracjmites communis var. berlandieri)

            The common reed (Phragmites communis var. berlandieri) occurs in
            the "triangle" near the railroad tracks and in an adjacent area.
            This species occurs in dense monotypic stands approximately 8.20
            feet (250 cm) in height; cover is 98 %. Common reed is rarely
            found in the marshes of Humboldt Bay; as such, this population
            may present a threat to the Humboldt Bay marshlands. The need
            for eradication of this species was previously discussed.

                                  Freshwater Marshes -- FM

            The marshes included in this section range from the upper edge of
            the brackish marshes to the riparian habitats (or willow swamps).
            The freshwater marshes include two tall, emergent dominated
            marshes and one emergent/floating-leaved marsh. These marshes
            are typical of Humboldt Bay. Some have previously been described
            by Monroe (1973), Newton (in Koplin, et. al. 1984), and Newton
            (1984, 1985a, 1985b).

            These freshwater marshes are extensive within the site and
            intergrade heavily with adjacent riparian areas. Similar
            freshwater marshes can be found around Humboldt Bay but are
            usually in narrow strips near grazed pastureland.

                                           B-6

                        FM     small-seed bulrush/water parsley/
                                       common rush
                        (Scirpus microcarpus Oenanthe sarmentosa/
                              Juncus effusus var. brunneus)

            This marsh is found on the "brackish side" of the cat-tail stands
            or the riparian areas.    These areas are dominated by the small-
            seeded.bulrush  'Scirpus microcarpus), occasionally in nearly
            monotypic stands, with some amounts of water parsley (Oenanthe
            sarmentosa) and common rush (Juncus effusus var. brunneus). The
            height of these marshes is 3.28 feet (100 cm); cover is 100%.
            This vegetation type intergrades in some areas with the extensive
            BM4 -- salt rush/pacific silverweed/common rush/water parsley.
                                 FN2 __  common cattail
                                     (Typha latifolia)

            Cattails (Typha latifolia) are the dominant species in this
            marsh. The stands can be either closed with a few incidental
            species occurring underneath the dense layerof cattails, or the
            stand can be more open with various species underneath. The
            species likely to found underneath the cattails are pacific
            silverweed (Potentilla egedii spp. grandis), water parsley
            (Oenanthe sarmentosa), bedstraw (Galium trifidium), willow herb
            (Epilobium watsonii var. franciscinum), common rush (Juncus
            effusus var. brunneus), monkeyflower (Mimulus guttatus ssp.
            litoralis), and slough sedge (Carex obnupta). The height of the
            stands averages 7.22 feet (220 cm); cover is 100%.

                         FM3 __ water parsley/marsh pennywort/
                                      floating fern
                     (Oenanthe sarmentosa/Hydrocotyle ranunculoides/
                                   Azolla filicuoides)

            There is only one location on the site where this marsh occurs in
            a large enough area to be mapped. This location is the remnant
            of the original freshwater pond present in the 1962 aerial photo
            of the site. In this area water parsley (Oenanthe sarmentosa) is
            the dominant species with marsh pennywort (Hydrocotyle
            ranunculoides) and spike rush (Eleocharis macrostachya) present
            in lesser amounts. Duckweed (Lemna sp.) and floating water fern
            (Azolla filiculoides) can seasonally cover all the areas of open
            standing water. The height of the plants above the standing
            water in this marsh varies depending on the presence of the
            rooted-emergents, 0.98 feet (30 cm), or the presence of the
            floating species, 0.03 feet (1 cm); cover averages 98%. _.

            In addition to the one location of this vegetation type included
            on the map, this marsh type is found throughout the freshwater
            marshes in small openings between plants. These areas, though
            important, are much too small to be accurately mapped.

                                           B-7

                        Riparian Woodlands (or Willow Swamps) -- R

           The riparian woodlands on the sites are present in abundance
           around the east edges. Two riparian vegetation types are
           delineated based on the herbaceous layer. R contains typical
           marsh species in the understory while R coniains dense
                                                  2.
           blackberry hedges and various grass species in the understory.

           The areas distinguished as R1, or "wet-site riparian", should be
           divided into two types based on the USFWS definitions (USFWS
           1979). A forested wetland is 32.8 feet (10 meters) in height; a
           scrub-shrub wetland is 23 feet P meters) in height. The western
           edge of the Ri area near Highway 101 is slowly encroaching into
           the adjoining marshes as evidenced by the large number of alder
           and willow saplings in that area. According to USFWS
           definitions, the area of encroachment should be designated as
           scrub-shrub wetland, while the more mature stand would be
           designated as forested wetland (despite its identical species
           composition). In effect, the scrub-shrub designation, in this
           particular case, is a transitional or successional stage of the
           forested wetland.

                           R, -- willow/alder/water parsley
                    (Salix spp./Alnus oregona/Oenanthe sarmentosa)

           This first type of riparian habitat is currently expanding from
           the area near Highway 101. This vegetation type is very similar
           in composition and structure to areas described by Newton (in
           Koplin et al 1984), Newton (1985a, 1985b). In the canopy layer,
           red alders (Alnus oregona) and one species of willow (Salix
           lasiandra) reach 30-40 feet (9-12 meters) in height. Other
           willow species (S. piperi and S. hookeriana) form a secondary and
           shorter layer at7aining 15 feeT_(_Z_.57 meters) in height. The
           overall cover of the canopy ranges from 60-90%. The tree species
           are invading the adjacent freshwater marshes; many saplings are
           becoming established in the marshes.

           The herbaceous layer of the riparian habitats is highly
           influenced by the type of marsh adjacent to each area, but
           typically contains, in dense stands (averaging 80% cover), some
           or all of the following moisture loving species: water parsley
           (Oenanthe sarmentosa), slough sedge (Carex obnupta), common cat-
           tail (Typha latifolia), and small-headed bulrush (Scirpus
           microcarpus).

                             @2 -- willow/alder/blackberry
                         (Salix spp./Alnus oregona/Rubus spp.)

           The second type of riparian habitat is found mainly west of the
           railroad tracks in the drier areas. The canopy is usually not as
           dense (approximately 40% cover) or as tall as the previous
           vegetation type; however, the same species of willow and red
           alder are present. The shrub layer is very dense and dominated
           by blackberry and himalaya berry (Rubus vitifolius and R.
           procerus). The herbaceous layer contains many of the iiime

                                          B-8

           species found in the adjacent grasslands such as vernal grass
           (Anthoxanthum oderatum) and orchard grass (Dactylus glomerata).

                                       Upland Habitats

                            G -- velvet grass/common rush
                     (Holcus lanatus/juncus effusus var. brunneus)

           These grasslands are located in areas very near marshes and
           contains many weedy species as well as some marsh species. The
           dominant grass species is velvet grass (Holcus lanatus). Species
           commonly associated with this type are creeping buttercup
           (Ranunculus repens), common rush (Juncus effusus var. brunneus),
           willow herb (Epilobium watsonii var. franciscanum), and pacific
           silverweed (Potentilla egedii ssp. grandis). The height of these
           grasslands averages 2.30 feet (70 cm); cover is usually 100%.

                          G2 -- perennial ryegrass/perennial
                                        trefoil
                          (Lolium perenne/Lotus corniculatus)

           This grassland contains many weedy species commonly associated
           with dry areas near the coast. The dominant grass species are
           perennial ryegrass (Lolium perenne), vernal grass (Anthoxanthum
           oderatum), bentgrass (Agrostis sp.), and orchard grass (Dactylus
           glomerata). Other species commonly found in this vegetation type
           are dubious clover (Trifolium dubium), Parentucellia viscosa,
           english plantain (Plantago lanceolata), anise (Foeniculum
           vulgare), beach strawberry (Fragaria chiloensis), and cat's ear
           (,Hypochoeris radicata). Height is variable; cover is usually
           100%.

                       B -- blackberry/coyote bush/wax myrtle

           This designation is used for small, isolated bushes of any or all
           of the following species: blackberry (Rubus vitifolius), himalaya
           berry (R. procerus), salmonberry (R. spectabilis), coyote bush
           (BacchaFl:-s pilularis ssp. consanguinea), wax myrtle (Myrica
           californica), and twin berry (Lonicera involculata). Height and
           cover varies with the species.

                                          B-9

               "MMIX B. OOMPMM SPBCIES LIST FOR THE PAIM MARSH CCMPIEX

               SCIENTIFIC NAME                        FAMILY             COMMON NAME

               Achillea borealis                      Asteraceae         yarrow

               Agrostis stolonifera                   Poaceae            creeping beent

               Aira caryophyllea                      Poaceae            hairgrass

               Alnus oregona                          Betulaceae         red alder

               Alopecurus genticulatus                Poaceae            water foxtail

               Ambrosia chamissonis                   Asteraceae         beach bur

               Angelica hendersonii                   Apiaceae           angelica

               Anthoxanthum oderatum                  Poaceae            vernal grass

               Aster chilensis                        Asteraceae         aster

               Atr@plex patula ssp. hastata.          Chenopodiaceae     orache

               Atriplex patula  ssp. obtusa           Chenopodiaceae     orache

               Avena sativa                           Poaceae            oat

               Azolla filiculoides                    Salviniaceae,      floating fern

               Baccharis pilularis ssp.               Asteraceae         coyote bush
                   consanguinea.

               Bellis perennis                        Asteraceae         english daisy

               Briza maxima                           Poaceae            rattlesnake grass

               Bromus mollis                          Poaceae            brome grass

               Bromus rigidus:                        Poaceae            soft chess

               Calystegia soldanella                  Convolvulaceae     beach morning-glory

               Carex lyn2@:Lei                        Cyperaceae         sedge

               Carex obnupta                          Cyperaceae         slough sedge

               Carex pansa                            Cyperaceae         sand dune sedge

               Cirsium sp.                            Asteraceae         thistle

               Cortaderis selloana.                   Poaceae            pampasgrass

                                                       B-10

                 SCIENTIFIC NAME                        FAMILY              COMMON NAME

                 Cotula coronopifolia                   Asteraceae          brass buttons

                 Cyperus eragrostis                     Cyperaceae          umbrella sedge

                 Cytisus monspessulanus                 Caesalpinaceae      french broom

                 .Cytisus scoparis                      Caesalpinaceae      scotch broom

                 Dactylis glomerata                     Poaceae             orchard grass

                 Daucus carota                          Apiaceae            Queen Anne's lace

                 Deschampsia caespitosa                 Poaceae             tufted hairgrass

                 Dipsacus sylvestris                    Dipsacaceae         teasel

                 Distichlis spicata                     Poaceae             salt grass

                 Eleocharis macrostachya                Cyperaceae          spike rush

                 Elymus mollis                          Poaceae             dunegrass

                 EpilcbilLun angustifolium              Onagraceae          fireweed

                 Epilobium watsonii var.                Onagraceae          willow herb
                     franciscanum

                 Equistem arvense                       Equisetaceae        horse tail

                 Erechities prenanthoides               Asteraceae          fireweed

                 Festuca. arundinacea.                  Poaceae             meadow fescue

                 Festuca sp.                            Poaceae             fescue

                 Foeniculum vulgare                     Apiaceae            anise

                 Fragaria chiloensis                    Rosaceae            beach strawberry

                 Fuchsia sp.                            Epilobium           fuchsia

                 Galium trifidum                        Rubiaceae           bedstraw

                 Geranium spp.                          Geraniaceae         cranesbill

                 Grindelia stricta ssp. blakei          Asteraceae          Humboldt Bay 9-wVlant

                 Hedera helix                           Araliaceae          English ivy

                 Heracleum lanatum                      Apiaceae            cow-parsnip

                 Holcus lanatus                         Poaceae             velvet grass

                SCIENTIFIC NAME                       FAMILY              COMMON NAME

                Hordeum sp.                           Poaceae             barley

                Hydrocotyle  ranunculoides            Apiaceae            marsh pennywort

                Hypochoeris radicata                  Asteraceae          cat's ear

                Jaumea. carnosa                       Asteraceae          jaumea

                Juncus effusus, var. brunneus         Juncaceae           common rush

                Juncus effusus  var. pacificus        Juncaceae           pacific rush

                Juncus ensifolius                     Juncaceae           rush

                Juncus lesueurii var.lesueurii        Juncaceae           salt rush

                Juncus lesueurii var. tracyi          Juncaceae           salt rush

                Lathyrus latifolius                   Fabaceae            everlasting pea

                Lemna spp.                            Lemnaceae           duckweed

                Leontodon leysseri                    Asteraceae          hawkbit

                Limonium californicum var.            Plumbaginaceae      sea lavender
                    californicum

                Lolium multiflorum                    Poaceae             Italian ryegrass

                L,oli  perenne                        Poaceae             perennial ryegrass

                Lonicera involculata                  Caprifoliaceae      twin berry

                Lotus corniculatus                    Fabaceae            perennial trefoil

                Lupinus sp.                           Fabaceae            lupine

                Lupinus arboreus                      Fabaceae            bush lupine

                Melilotus albus                       Fabaceae            sweet-clover

                Mentha pulegium                       Lamiaceae           pennyroyal

                Mimulus guttatus ssp. litoralis       Scrophulariaceae    monkey flower

                Myrica californica                    Myricaceae          wax mrytle

                Oenanthe samentosa                    Apiaceae            water parsley

                Parentucellia viscosa                 Scrophulariaceae

                                                      B- 12

                  SCIENTIFIC M*E                           FAMILY               COMMW NAME

                  Phragmites commis var.                   Poaceae              coffmn reed
                       berlandieri

                  Plantago lanceolata,                     Plantaginaceae       english plantain

                  Plantago maritima ssp. juncoides         Plantaginaceae       sea plantain

                  Poa annua.                               Poaceae              annual bluegrass

                  Poa douglasii                            Poaceae              dune bluegrass

                  Polypogon maritimus                      Poaceae              rabbitfoot grass

                  Polystichum munitum                      Aspidiaceae          sword fern

                  Potentilla egedii ssp. grandis           Rosaceae             pacific silverweed

                  Prunella vulgaris                        Lamiaceae            selfheal

                  Pteridium aquil        var.              Pteridaceae          bracken fern
                      pubescens

                  Ranunculus repens,                       Ranunculaceae        creeping buttercup

                  Raphanus sativus                         Brassicaceae         wild radish

                  Rosa sp.                                 Rosaceae             rose

                  Rosa nutka                               Rosaceae             nutka rose

                  Rubus procerus                           Rosaceae             himalaya, berry

                  Rubus spectabilis                        Rosaceae             salmonberry

                  Rubus vitifolius                         Rosaceae             blackberry

                  Rumex acetosella                         Polygonaceae         commn dock

                  Fomiex crispus,                          Polygonaceae         curly-leaved dock

                  Ruppia maritima                          Ruppiaceae           ditch grass

                  Salicomia virginica                      Chenopodiaceae       pickleweed

                  Salix hookeriana                         Salicaceae           hooker's willow

                  Salix lasiandra                          Salicaceae           willow

                  Salix piperi                             Salicaceae           dune willow

                  Sci.rpus americanus                      Cyperaceae           tbree-corner

                                                           B-13

                 SCIENTIFIC NAME                        FAMILY             COMMON NAME

                 Scirpus microcaxpus                    Cyperaceae         small-seeded bulrush

                 Scirpus robustus                       Cyperaceae         saltmarsh bulrush

                 Scrophularia. californica              Scrophulariaceae   figwort.

                 Spartina densiflora                    Poaceae            cordgrass

                 Spergularia marina                     Caryophyllaceae    mud-spurrey

                 Stachys sp.                            Lamiaceae          hedge nettle

                 Stellaria. sitchana var.               Caryophyllaceae    chickweed
                    bongardiana

                 Tanacetum douglasii                    Asteraceae         dune tansy

                 TaraxacLun officinale                  Asteraceae         dandelion

                 Trifolium dubium                       Fabaceae           dubious clover

                 Trifolium repens                       Fabaceae           creeping clover

                 Trifolium wormskioldii                 Fabaceae           cow clover

                 Triglochin concinnum                   Juncaginaceae      slender arrow grass

                 Triglochin maritimum                   Juncaginaceae      arrow grass

                 Typha latifolia.                       Typhaceae          cattail

                 Veronica scutellata                    Scrophulariaceae   speedwell

                 Vicia angustifolia var.                Fabaceae           vetch
                     segetalis

                 Zostera. marina                        Zosteraceae        eel grass

                                                        B-14

                                             APPENDIX C

                                   ESTIMATED CONSTRUCTION COSTS_
                              FOR THE PALCO MARSH ENRANCE14ENT PROJECT

                Project                               Quantity        Unit      Construction
                Element                                           Price($)      costs M

                HABITAT  ENHANCEMENT

                Water Exchange Improvements         Lump Sum        10,000      10,000
                  (Inverted Siphon/Weir, etc.)

                Channel Excavation                     87 cy           10        8,750
                Hand-ditching                         300 If             3.20        960

                Open Water Pond Excavation/         14800 cy           10      148,000
                Temp. Road Construction               750 cy             6       4,500

                Removal of Drying Sheds             Lump Sum        5,000        5,001
                Removal of Paving                  28,500 sf             0.15    4,275
                            Gravel                  1,600 cy             6       9,600

                RR Marsh Excavation                 3,200 cy             8      25,600

                Maintenance Road
                Improvements(gravel)                  500 cy             6       3,000

                Vegetation Removal/
                Revegetation                        Lump Sum       25,000       25,000

                                                               Sub Total       $244,685

                PUBLIC ACCESS

                Del Norte Street Improvements
                     Parking Area     Base           260 cy            25        6,500
                                     Paving       14,000 sf              0.80   11,200
                     Kiosk                         Lump Sum         1,000        1,000
                     Gates                             2 ea           400           800
                     Picnic Tables                     4 ea           300        1,200
                     Raised Viewing Area           2,200 cy              6      13,200

                Vigo Street Improvements
                     Access Barrier/Bumper Logs    1,000 If              1       1,000
                     Gates                             2 ea           400            800
                     Signs                         Lump Sum         1,000        1,000
                     Benches                           8 ea           250        2,000

                                                                Sub Total      $38,700

                Sidewalks- Del Norte St.             540 If            54       29,160
                           Felt St.                  600 If            56       33,600
                            Broadway                 530 If            68       36,040

                                                                Sub Total      $98,800

                MONITORING (up to 4 years)          1,000 hrs          30       30,000

                                                        Contingency 10%        $41,200

                                                           OVERALL TOTAL       $453,385
                                                   C -.1

                                                                                                                                     BROADWAY

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                                                                                                                                     NOAA COASTAL SERVICES CTR LIBRARY

                                                                                                                                     3 6668 14110030 7