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Vf I z z 0 CA 1632 COASTAL ZONE INFORMATION CENTER Environmental Health Admimstration MARINA CONTRIBUTION TO BACTERIAL WATER QUALITY POLLUTION IN KENT ISLAND NARROWS., MARYLAND Maryland GC Department of Health and 1212 M3 Mental Hygiene M3 1979 EH:WSC:GS #2 Property of CSC Library U.S. DEPARTMENT OF COMMERCE NOAA COASTAL SERVICES CENTER 2234 SOUTH HOBSON AVENUE CHARLESTON, SC 29405-2413 MARINA IMPACT ON WATER UALITY IN KENT ISLAND NARROWS, MARYLAND Mary jo Garreis, Faith A. Pittman Donald L. Elmore, Robert L. Robison, II Environmental Health Administration Maryland Department of Health and Mental Hygiene August, 1979 GC 1212.M3 M3 1979 15024973 Jan 23 1997 ACKNOWLEDGEMENT The many water samples necessary for this project were collected by Mr. Clarence Dean, Mr. By rqn Fairall and Mr. Archie Fitzgerald of the Department of Health and Mental Hygiene's Environmental Health Adminis- tration often under inclement weather conditions. Laboratory analyses were made by Mr. Daniel Spielman, Bacteriologist in charge of the Easton Branch Laboratory and the staff of the Easton Branch Laboratory, Laboratories Administration, Department of Health and Mental Hygiene. Special thanks go to Mrs. Nancy Manley for typing the many drafts and final manuscript of this report. Mr. Arnold C. Salinger, Assistant Chief, Division of Microbiology, Laboratories Administration, Department of Health and Mental Hygiene, is gratefully thanked for his encouragement and constructive criticism during the course of this study and the preparation of the final report. The preparation of this project was funded in part by the Maryland Coastal Zone Management Program, TABLE OF CONTENTS Page Introduction ........................................................................... I Study Area Description ........................... ;............. ..... .................... 2 Identification of Potential Pollution Sources ................................... ............. 5 Seafood Processing Plants ... ....................................................... 5 Sewage Treatment Plants .............................................................. 8 On-Site Waste Disposal Systems ........................................................ 8 Marinas ........................ I......................................... I ......... 8 Study Approach ......................................................................... 11 Methodology ............................................................................ 14 Sample Collection and Analysis. ....................................................... 14 Statistical Analysis .................................................................. 14 Results ................................................................................ 16 Seafood Processing Plants ............................................................ 16 On-Site Waste Disposal Systems ........................................................ 16 Marinas ............................................................................ 16 Discussion .......................................................................... ... 24 Conclusion .......* ...... 26 References ............................................................................. V Appendix .............................................................................. 28 LISTING OF TABLES Page Table 1 - Seafood Processing Plant Effluent Sample Results ................................... 7 Table 2 - Fecal Coliform Level in Kent Island Narrows Compared to Fecal Coliform Levels in Six Marinas ...................................................... 17 Table 3 - Total Coqorm Level in Kent Island Narrows Compared to Total Coqorm Levels in Six Marinas ........................................................... 18 Table 4 - Fecal Coliform Levels in the Chester River and Prospect Bay Compared to Fecal Coqorm Levels in Six Marinas ............................................... 19 Table 5 - Comparison of Total and Fecal Col6form Levels in Control Areas ...................... 20 Table 6 - Comparison of Fecal Coliform Levels in Marina Waters on Days Following Weekends or Holidays with Days During the Week .................................. 21 Table 7 - Loglo Means for Fecal Coliform Densities in Piney Narrows Marina and Seward's Point Marina ...................................................... 21 Table 8 - Station Compliance with National Shelyi@h Sanitation Program Standards for Fecal Coliform ............................................................. 22 LISTING OF FIGURES Page Figure I - Chesapeake Bay with Kent Island Narrows Region Enclosed ................. 3 Figure 2 - Restricted Shellfish Harvesting Area in Kent Island Narrowsa'nd Prospect Bay ........... 4 Figure 3 - Location of Seafood Processing Plants in Kent Island Narrows ......................... 6 Figure 4 - Piney Narrows Sewage Treatment Plant Location ................................... 9 Figure 5 - Kent Island Narrows Marinas ................................................... 10 Figure 6 - Sampling Station Locations in Kent Island Narrows and Prospect Bay .................. 12 Figure 7 - Sampling Station Locations in the Chester River .................................... 13 iv INTRODUMON The actual impact on water quality caused by he overboard discharge of sewage wastes from boats in marinas is an issue that has been debated for many years. This issue is of particular interest in the Kent Island Narrows where many commercial fishing boats and recreational vessels are located in a small geographical area. Bacteriological water quality in Kent Island Narrows has been unsatisfactory for many years resulting in the restriction of valuable shellfish growing waters by the Maryland State Department of Health and Mental Hygiene. No previous studies or data have been generated to determine the impact marinas may have on bacterial water quality in the Kent Island Narrows. Additional sampling stations were added to the routine water quality monitoring network already established in this area. Data generated from these additional stations were used to study the impact boating activity may have on bacterial water quality in Kent Island Narrows. STUDY AREA DESCRIPTION Kent Island Narrows is a small body of water separating Kent Island on the west from the Eastern Shore main- land on the east. Both Kent Island and Kent'Narrows are located in Queen Anne's County (Figure 1). The Narrows, as it is commonly known, is navigable to vessels with entrances from the Chester River to the north and Eastern Bay to the south. It is approximately one mile long and one hundred and seventy yards wide with a dredged deep water channel running the entire length of the Narrows near the east shoreline. The channel ranges from eight to eighteen feet in depth. Good tidal exchange occurs in the Narrows because the tides in Eastern Bay and the Chester River are out of phase. The topography of Kent Island is an almost level plain less than twenty feet above sea level in most places and barely above high tide near the Narrows. Few streams dissect the surface of this plain, but small bays branching off from the Chesapeake Bay indent the shores and create many narrow peninsulas. The tide and current movement through Kent Island Narrows can be described as a driving force acting on a relatively small body of water. Regular tidal motion in the Narrows consists of water entering the Narrows as a broadly distributed flow and exiting as a high velocity jet confined by the channel. I On flood tide. the water moving into the Narrows from Eastern Bay is probably concentrated on the eastern side of the channel off Wells Cove as a deep moderated velocity flow. The water exiting the Narrows at the northern end into the Chester River is con- centrated into a narrow high velocity jet along the dredged channel. During the ebb tide, a broadly distributed flow of water enters the narrows from the Chester River following the boundaries of the channel and exits as a high velocity jet into Prospect Bay. The flood tide is stronger on the eastern side of the Narrows; the ebb tide shows a stronger flow on the west side. It has been suggested that this difference is probably a result of the curvature in the channel. The strong tidal current flow occuring in the Narrows is attributed to the 1.5 hours phase difference between the tidal flows in the Chester River and Eastern Bay.2 The concentration of the exiting flow into a high velocity jet allows the water to travel some distance into the Chester River on the flood tide or Eastern Bay on the ebb tide before it slows and spreads into a broad plume. This further dispersal presumably results in less return flow and hence less pollutant accumulation in the Narrows. Because of the 1.5 hours phase difference between the tidal flows in Eastern Bay and the Chester River, the flood tide in the Chester River occurs later than the flood tide through the Narrows. The delay results in the water exiting northward through the Narrows being carried up the Chester River on the flood tide. This in turn causes less return flow and presumably lower pollutant concentrations in the Narrows region. The wind can alter or impede the flow of water through the Narrows. A strong wind driven flow of water can dominate the flow overriding the semidiurnal tide .3 The shellfish waters of Kent Island Narrows have been closed for extended periods of time by the Department of Health and Mental Hygiene in the past ten years because of excessive fecal coliform bacteria levels. Six hundred and sixty-five (665) acres of surface waters and sixty-six (66) acres of public oyster bars are currently restricted for shell- fish harvesting (Figure 2). This shellfish harvesting area is extremely important to the shellfish industry as it is sheltered from winter winds. In addition, since the swift tidal action impedes ice formation, shellfish harvesting can continue here when other areas are closed by inclement weather conditions. Restriction of this area because of poor water quality causes economic hardship to the industry. 1. W. C. Boicourt, Measurement of Tides and Currents in Kent Island Narrows, Open File Report No. 11, Chesapeake Bay Institute, Johns Hopkins University, February, 1978. 2. Ibid. 3. Ibid. 2 Chester iver CW Oa Figure I Chesapeake Bay with Kent Island Narrows Region Enclosed KENT ISLAND NARROWS CHESTER RrVER Lonq Point Ro"t,.,S,0 Hoq Island -MARSHY CREEK PROSPECT SAY Figure 2 Restricted Shellfish Harvesting Area in Kent Islands Narrows and Prospect Bay IDENTIFICATION OF POTENTIAL POLLUTION SOURCES Possible sources of bacterial pollution in Ken, Island Narrows include seafood processing plants, fail septic systems and marinas. No one source has been identified as the principal cause of problems in the area. Seafood Processing Plants Seafood processing plants have been su�pected of contributing to the bacterial pollution load in the Narrows since wastewater from seafood processing operations is discharged directly overboard. No seafood processing plants are located on the western shore of the Narrows although eight seafood processing plants operate along the eastern shore (Figure 3). Oysters, softshell clams and crabs are the main seafood products processed. Softshell clams and crabi are processed on a year-round basis whereas oysters are processed from September through April. Various amounts of wastewater are produced at the seafood plants during processing and in the cleaning of equipment and work areas at the end of the work day. In seven of the seafood processing plants, the wastewater drains into a single concrete trough running the length of the plant. Twenty mesh screens are placed at several locations in the trough to catch any solid materials that could be discharged with the wastewater. Disinfection of the effluent is accomplished through the use of chlorine tablets placed in the troughs. This straight flow discharge elimination type system results in inadequate disinfection because of limited chlorine contact time and the high organic demand of the effluent. Fisherman's Seafood Market uses a baffled concrete tank to receive wastewater from the plant allowing solids to settle out before the effluent is discharged. Chlorine tablets are also the method of disinfection used with this system. The effluent from all the seafood processing plants is discharged directly into the channel waters of the Narrows. Effluent data from the Enforcement Division, Water Resources Administration, Department of Natural Resources, indicates that these seafood processing plants discharge effluent which is high in total coliform and fecal coliform bacteria. Eight seafood processing plants were inspected and effluent samples collected for compliance monitoring by the Water Resources Administration, during 1975 and 1976. Effluent data for 1974 was not available. Seven of these plants were not in compliance with the bacteriological requirements of their National Pollution Discharge Elimination System (NPDES) permit most of the time. These permits require that the total coliform level in discharged effluent notlexceed 70 MPN/100 ml. Effluent data collected from the sampling of these plants is presented in Table 1. Seafood processing plants in Kent Island Narrows that discharge effluents high in total coliform and fecal coliform bacteria may be considered as a contributory source toward the overall pollution of waters in the Narrows. The volume of wastewater discharged from these seafood processing plants is based on the daily output of products processed. If a large amount of seafood is processed on a given day then the volume of wastewater produced daily is proportionately large. The opposite is true if a small amount of seafood is processed. Since no data are available on the actual volume of effluent discharged from the seafood processing plants, it is difficult to determine the impact these effluents have on bacteriological water quality in the Narrows. Two different means of human waste disposal serve the seafooa processing plants. Privys and chemical toilets provide the means of human waste disposal for the plant workers while indoor toilet facilities serviced by a septic system serve the needs of the office workers. The outdoor facilities are located inland some distance from the shoreline of the Narrows. Because of their location away from the water, it is not believed that sewage from these privys and chemical toilets would seriously affect the waters of the Kent Island Narrows. The septic systems serving the indoor bathroom facilities of the seafood plants have been known to fail. 5 KEW ISLAND NARROWS CHESTLFR RIVER Long Point co 0 'Rout so Bog Island KARSHY CREEK PROSPECT BAY A - W.H. Harris Seafood, Inc. E - Fisherman's Seafood Market B - Kent Oyster Company F - W.A. Thomas and Son C - United Shellfish Company G - H.S. Thompson, Inc. D - B.J. Seafood, Inc. H - B and S Fisheries, Inc. Figure 3 - Location of Se afood Processing Plants in Kent Island Narrows 6 Table 1 Seafood Processing Plant Effluent Sample Results TABIA 1 - Seafood Processing Plant zffluent sample Results Total Coliform Oecal Coliiarm Seafood Procewsin@ Plants Date IMPNI100 mi MPN/100 =I Borman D. Thompson Outfall 1 10/28/7S 23,000 430 10/29/75 240,000 4j300 Outfall 1 -3/16/76 3 Outfall 2 3/16/76 210;000 4,300 Outfall 1 12/7/76 43,000 93 W.A. Thomas and Sons 3/16/76 3 3 -w ----------- - --------- a. and S. risheries Outfall 1 11/24/75 9,300 150 3/16/76 43,000 430 8/3/76 3 3 12/7/76 4 3 Islander Seafood 6/3/75 460,000 936 Primary outfall 10/1/75 9,300,000 11500 10/l/75 2,300 15 Outfall 1 11/24/75 15,000 23 ------- - - -- - ----- - --- --------------- - ---- - - ------- - ------------- United Shellfish Co.Outfall 2' 10/8/75 23,000 430 Outfall 2 .3/16/76 240,000 150 Outfall 1 5/12/76 3 3 Outfall 1 8/3/76 2,400,000 240,000, 12/28/76 2,400,000 93 2/8/77 150,000 3 rishermans Seafood market 10/l/75 3 3 Outfall 1 10/28/75 43,000 930 Outfall 1 3/16/76 3 3 - ---- - --------- - ------ ----- Kent Oyster Company Outfall 1 10/8/75 240,000 23,000 W.H. Harris Seafood Outfali 1 10/8/75 39,000 4,300 SOUFAMs Enforcement Division, water Resources Administration, Department of Natural Resources 7 Sewage Treatment Plants An activated sludge sewage treatment plant serving a small condominium housing seventeen people is locate on the ground of the Piney Narrows Marina. This plant has a design flow of .024 million gallons per day (MGD). The daily flow from this plant, however, is well below the designed flow and ranges from .001 to .007 million gallons per day. Based on inspections and analyses of effluent samples, the performance rating of this plant is in compliance with its NPDES permit. The treated effluent from this plant is discharged into the Chester River through an unnarned tributary and is not believed to have any effect on water quality in Kent Island Narrows. The location of the Piney Narrows Sewage Treatment Plant and its discharge point is shown in Figure 4.4 On-Site Disposal Systems Failing on-site waste disposal systems have been suspected of contributing to the bacteriological pollution load entering the waters of Kent Island Narrows either by direct discharge or from runoff occurring after heavy precipitation. On-site waste disposal systems in Kent Island Narrows serve several marinas and their offices, most of the seafood processing plant offices, two restaurants (Poiseidon Inn and Fishermans Inn), and a few individual homes. Soils in the Kent Island Narrows area are classified as,. Tidal Marsh and Made Land soils with Tida_l Marsh. being the dominant type. Tidal 1.1farsh soils have severe 'limitations for disposal of sewage effluent from sq@@ti,.: tank,@ and for use as sewage lagoons because of tidal flooding. Made Land soils consist of areas where the soii zni@v,-rial has been disturbed or modified by man and can no longer be identified by soil series or soil type. This soil IiE.,.s r1-o agricultural value and is used for residential and commercial purposes only. Marinas There are ten marinas in Kent Island Narrows serving both pleasure and work boats. Three of the marinas are located on the west shore of the Narrows and seven are located on the east shore (Figure 5). The names of these marinas and the number of slips available are listed below. Name Number of Slz)5s Hartge Boat Yard ....................... 26 Thomas Boat Yard ...................... 6 Cedar Point Marina, Inc .................. 100 Fisherman's Marina, Inc .................. 45 W. A. Thomas and Son, Inc ............... 2 (Party Boats) Kent Narrows Marina .................... 50 Seward's Point Marina ................... 405 Piney Narrows Marina and Yacht Sales ........ *. @ ................ 274 Kent Island Yacht Club .................. 41 County Marina ......................... 91 TOTAL NUMBER OF SLIPS 1040 Source: Boating Almanac 1977, Boating Almanac Company, Volume 4, Severna Park, Maryland, 1977. The actual effects of boating activity on the environment are difficult to is olate and assess. It is generally accepted that high intensity boat activity can result in: 1. Degradation of water quality and aquatic biota due to overboard discharge of human wastes and litter. 2. Reduction of water flushing capabilities due to structure encroachment. 3. Degradation of water quality and aquatic biota due to discharge of engine emissions and unburned fuels.' 4. Official Record, Division of Water Supplies, Water and Sewage Control Programs, Environmental Health Administration, Department of Health and Mental Hygiene 5. Maryland Department of Natural Resources Water Resources Administration, Chester River Basin Water Quality Management Plan, Annapolis, Maryland, 1976. 8 KENT ISLAND NARROWS CHESTER RIVER Long Point Point of Disch&rae Piney Narrow M ;5 sewage Z. Treatmen lan 0 A Rout, Hog Island KARSHY CREEK PROSPECT BAY Figure 4 Piney Narrows Sewage Treatment Plant Location 9 CHESTER RIVER CA -Oz U3 24 Rout, S0 Hog Island Prospect Bay MARSFrY CREEK A - Seward's Point Marina F - Fisherman's Marina B - Piney Narrows xarina G - Thomas 3oat Yard C - County Marina H - Hartge's Boat Yard 0 - Kent Island Yacht Club I - Cedar Point Marina E - Kent Narrows Marina J - W.A. Thomas and Sons Marina L Figure 5 Kent Island Narrows Marinas 10 STUDY APPROACH In April of 1974, personnel from the Division of General Sanitation established a special water sampling program in Kent Narrows at the request of Dr. Roberta Hall, Deputy State and County Health Officer for the Queen Anne's County Health Department. The purpose of the program was to monitor water quality in Kent Island Narrows marinas for the presence of total coliform and fecal coliform organisms as indicators of sewage pollution from boats. Total coliform and fecal coliform are indicator organisms used in assessing the bacteriological quality of water. The coliform group of bacteria are found in the guts and feces of warmblooded and coldblooded animals, In soils and on many plants. The fecal coliform organisms, however. are usualiv associated only with the enteric tract of warmblooded animals. The feces of warmblooded animals such as humans, animals and birds may also contain disease producing microorganisms at any time.' The coliform group, particularly fecal coliform, are therefore used as an indicator of the possible presence. in water of sewage bearing disease -producing microorganisms. 'The waters in Kent Island Narrows are classified as shellfish growing waters and are highly productive for oyster shellstock. Oysters are filter feeders that strain detritis and phytoplankton from the water for food. If harmful bacteria or viruses are present in the growing waters, they are concentrated within the oysters. When the oysters are consumed in a raw or partially cooked state by humans, the harmful microorganisms concentrated within the oyster may produce illness. Where concentrations of boats equipped with toilets discharging untreated wastes overboard occur, a potential hazard to human health exists if the receiving waters are used for growing shellfish such as clams, oysters or mussels. At the beginning of the program, twenty-three sampling stations were randomly established at various locations in and around Kent Island Narrows. Upstream and downstream locations were included to monitor the extent of bacteriological loading leaving or entering the Narrows during tidal changes and current flows. Figure 6 shows the sampling station locations, in Kent Island. Narrows and Prospect Bay. Figure 7 shows sampling station locations in the Chester River. Ten sampling stations were established in the waters of six marinas to study the effect boating activity may have on water quality in the Narrows. Sampling stations were located as follows: Piney Narrows Marina - 3 sampling stations Seward's Point Marina - 3 sampling stations County Marina - I sampling station Kent Narrows Marina - I sampling station Hartge Boat Yard and Thomas Boat Yard - I sampling station Cedar Point Marina - 1 sampling station Figure 6 shows the sampling station location in or adjacent to these marinas. On February 14 and 15, 1974, a special shoreline survey of properties in the Kent Island Narrows area was done by personnel from the Division of General Sanitation. Thirty (30) commercial and residential properties were inspected for possible sanitary violations including failing septic systems, kitchen waste and laundry waste discharges. Ten (10) violations were discovered and reported to the Queen Anne's County Health Department for correction. All of the violations were corrected by March 15,. 1974, prior to the initiation of the study. Spot checks were made throughout the study on properties with a history of failures. No additional sanitary violations were found. 6. E. E. Geldreich, Sanitary Significance of Fecal Coliform in the Ent4ronment, U.S. Department of the Interior, November 1966. CHESTER RIVER 11F 22 23 n14 so 4 Hog Island MARSHY CREEK 17 PROSPECT SAY Figure 6 Sampling Station Locations in Kent Island Narrows and Prospect Bay 12 EASTERN NECK 0 ISLAND Hail Point Cedar PointO5, 1@ 44o, 11F n .4 arshy ei Creek Figure 7 Sampling Station Locations in the Chester River 13 METHODOLOGY Sample Collection and Analysis Surface water samples for coliform and fecal coliform analysis were collected monthly or more frequently at all established stations for a period of two years. Surface water samples were collected by securing 4 bottle to the base of a dipstick and lowering it over the side of a boat. All samples were collected in sterile bacteriological bottles using aseptic techniques. All water samples were iced and delivered to the Department of Health and Mental Hygiene's Regional Laboratory in Easton, Maryland. All sampling and examination procedures were conducted in accordance with Recommended Procedures for the Examination of Sea Water and,Shelyi@h, 4th Edition, 1970, No samples were collected for chemical analysis. All water samples collected in the course of the study were analyzed for the presence of the total coliform group and the fecal coliform group using a three- tube/three -dilution Most Probable Number Test. Results of tests for coliform organisms or for various members of the coliforin group by the multi-tube dilution method are reported in terms of the "Most Probable Number" (MPN) index. The MPN is not a precise enumeration of the numbers of bacteria in any given sample volume. The precision and confidence limits of the test using any given number of tubes and of the MPN method of estimating densities have been deter-mined and are available in the Recommended Procedures. The accuracy of the result is dependent upon the number of portions of each dilution planted in the multi-tube fermentation test. Statistical Analysis To adjust the data to a common scale, the total coliform and fecal coliform MPN values were transformed by logio. Data spanning a 2 year period from April of 1974 through May of 1976 were used and results from stations within marinas were combined to establish one mean for each marina. Data from the same period were used to establish a mean for each of the control areas. Results from monitoring stations 12, 13, 14, 15, and 17 were combined to obtain the mean for Prospect Bay waters. Stations 1117, 5, 9 and 12 were combined to obtain a mean for Chester River waters and stations 22, 23, 24, and 25 were used to obtain a mean for the Kent Islar id Narrows. Comparisons were made between total coliform and fecal coliform levels in marina waters and th ,waters in Prospect Bay, Chester River and the Kent Island Narrows (controls). The total coliform and fecal coliform levels from these three control areas were also compared to one another. In addition, fecal coliform levels within marina waters on the first day following a weekend or holiday were compared to levels within marina'waters on weekdays. Dunnett's procedure" of comparing all means with a control was used to compare levels of total coliform and fecal coliform in the waters of each marina with levels in each control water. A separate analysis of variance was performed for marina waters versus Kent Island Narrows (control); marina waters versus Prospect Bay waters (control) and marina waters versus the Chester RNer (control). + The significant difference d 'It's ki where t is from Dunnett's table, s equals the square root of the error mean square and + is a correction factor for variable replication where Xi and t i are the number of observations in the two means being compared, was calculated for each comparison. The difference between the means being compared -X in this case being the marina mean and X being the control mean, was declared significant if the difference was greater than the significant j I I difference, d' that was calculated for that particular comparison. 7. R. Steel and J. Torrie, Principles and Procedures of Statistics, McGraw Hill Book Company, Inc., New York, 1960, 14 Student's one-,ailed I-,es, was used to compare the total and fecal coliform, levels in the three control areas (Prospect Bay, Chester River and the Kent Island Narrows). The Student's one-tailed t-test was used to compare total and fecal coliform levels in the waters of a marina on a day following a weekend or holiday with levels in the waters of the same marina during the week. Data from 1974 and 1975 were used. Data from stations within each marina were combined to obtain one representative mean for weekdays or for the days following a weekend or holiday. 15 RESULTS The Kent Island Narrows Marina study began in April 1974 and ended in May 1976. All water quality monitoring stations were sampled monthly or more frequently. During this time period, six hundred and thirty-six (636) water samples were collected from 23 locations. The total and fecal coliform data generated over'the two year period are presented in the Appendix. Samples of effluent from seafood processing houses were 'Collected by the Water Resources Administration, Department of Natural Resources. Seafood Processing Plants Results of bacterial analyses of the effluents from eight of the seafood processing plants indicate that seven of these plants discharge effluents which exceed their NPDES limits of 70 MPN/100ml for total coliform. most of the time. All of the seafood processing plants discharge treated effluent directly into Kent Island Narrows. No known direct discharges from the processing plants enter the marina basins. No data are available on the actual volume of effluent discharged by these plants and it is, therefore, difficult to quantify the impact of these effluents on bacteriological water quality in the Narrows. Since the water quality in Kent Island Narrows was used as a control for comparison purposes with water quality in the marina basins and since the control includes the effects of the seafood processing plants, any elevated total or fecal coliform levels found in the marina basins should be related to marina activity and not to seafood processing plant wastes. On-Site Waste Disposal Systems Failing on-site waste disposal systems have been suspected of contributing to the total and fecal coliform pollution load entering the waters of Kent Island Narrows. A special survey was made of the study area prior to the initiation of the study. Discharges from on-site waste disposal systems which might contribute to the bacterial load in the waters of Kent Island Narrows or the marina basins were identified and eliminated. Periodic spot checks were made to assure that no additional failures occured. Water quality in the marina basins or Kent Island Narrows during the study period should not reflect any effect from on-site waste disposal systems. Marinas The total and fecal coliform MPN values from the waters of each marina and from each of the control areas were adjusted to a common scale by loglo transformation. Data spanned a two-year period from April 1974 through May 1976. Results from stations within each marina were combined to obtain a representative mean for each marina. Similarly, results from stations within each control area were combined to obtain a representative mean for each control area. A comparison between the fecal coliform level in Kent Island Narrows (control) and the level in the waters of each marina was made using Dunnett's procedure of comparing all means with a control. The difference between fecal coliform means for the control and for each of the six marinas ( Y' Xj ) along with the significant difference for each comparison d' was calculated and is shown in Table 2. The difference between the means being compared was declared significant if the difference was greater than the significant difference d' that was calculated for that particular comparison. All marina waters were found at the 5% level to have significantly higher fecal coliform levels than the waters in Kent Island Narrows. Dunnett's procedure was also applied to the total coliform data using the same process implemented in the evaluation of the fecal coliforin data. (Table 3) All marina waters were found to have significantly higher total coliforin levels than the waters of the Kent Island Narrows. 16 Table 2 Fecal Coliform Level in Kent Island Narrows Compared to Fecal Coliform Levels in Six Marinas Location d' Significant"* at the 5% level Seward's Point Marina .59 .22 + Piney Narrows Marina and Yacht Sales .60 .22 + County Marina 45 .32 + Cedar Point Marina .51 .35 + Hartge's Boat Yard .98 .38 + Kent Narrows Marina .42 .32 + --------------------------------------------------------------- xi marina fecal coliform mean; x.= Kent Island Narrows I fecal coliform mean **dl --Dunnett's significant difference significant To further test the hypothesis that marina waters have higher levels of fecal and total coliform. than waters outside of marinas, Dunnett's procedure was used to compare the marina waters to two other control areas. Data from the Chester River immediately north of the Kent Island Narrows was used as one control area while data from Prospect Bay immediately south of the Kent Island Narrows was used as a second control area. Results from the fecal coliform level comparison of marina waters to Chester River waters and to Prospect Bay waters are shown in Table 4. In all cases, marina waters were found to have significantly higher levels of fecal coliform than the waters of the Chester River or Prospect Bay. 17 Table 3 Total Col@(orm Level in Kent Island Narrows Compared to Total Coliform Levels in Six Marinas Location Tj - x j d Significant- at the 5% level Seward's Point Marina .41 .20 + Piney Narrows Marina and Yacht Sales .45 .20 + County Marina .50 .28 + Cedar Point Marina .55 .31 + artge's Boat Yard .60 .34 + Kent Narrows Marina .49 .28 + ----------------------------------------------------------- marina total coliform mean x Kent Island Narrows i total coliform mean. *od'= Dunnett's significant difference significant 18 Table 4 - Fecal Col@form Levels in the Chester River and Prospect Bay Compared to Fecal Col@form Levels in Six Marinas Chester Rivet (control) Prospect Bay (control) Location 3 ;-3Ej* Signif7a-nt***_r-_Xj* d. Significant"* at the at the 5% level 5% level Seward's Point Marina 1.06 .27 + .63 .21 + Piney Narrows 4arina and facht Club 1.01 .26 + .64 .21 + 'ounty 4arina .86 .37 + .49 .33 + Cedar Point Marina .92 .37 + .55 .33 + Hartge's , Boat Yard 1.39 .41 + 1.02 .36 + Kent Narrows Marina .83 .34 + .46 .30 + xi = marina fecal coliform mean; 4j = control fecal coliform mean dr = Dunnett's significant difference + = significant Dunnett's procedure was also applied to the total coliforin data to compare levels of total coliform in marina waters to levels in the waters of the Chester River and Prospect Bay. In all cases, total coliform levels in marina waters were significantly higher than levels in the two control areas. The Student's one-tailed t-test was employed to compare the total and fecal coliform levels in the three different control areas. (Table 5) The Chester River had significantly lower total and fecal coliform levels than the Kent Narrows and Prospect Bay areas. There is no significant difference in total and fecal coliform levels in Kent Narrows and in upper Prospect Bay, 19 Table 5 - Comparison of Total and Fecal Col@form Levels in Control Areas Total Fecal Coliform Significant* Coliform Significant* Axeas Compared Means at the Means at the 5% level 5% level Chester River 2.05 1.03 VS. VS. + VS. + Kent Narrows 2.25 1.44 ------------------------------- ---------------------- ------------ Chester River 2.05 1.03 VS. VS. + VS. + Prospect Bay 2.24 1.40 -------- --- ---- ---- Kent Narrows 2.25 1.44 VS. VS. VS. Prospect Bay 2.24 1.40 + = significant; not significant The Student's one-tailed t-test was applied to the data to compare fecal coliform levels in the waters of a marina on a day following a weekend or holiday to the fecal coliforin levels in the waters of the same marina during the week. (Table 6) The difference between the means being compared where "Zi is the mean for the days following weekends or holidays and Xj is the mean for days during the week is considered significant if it exceeds the t value for the 95% confidence level shown in Student's t Table. The 3 large marinas, Seward's Point, Piney Narrows and Cedar Point, which cater primarily to pleasure craft had significantly higher levels of fecal coliforin in marina waters on days following a weekend or holiday than on weekdays. Since the County Marina services only commercial fisherman who use their boats to work six days a week if weather conditions permit, it is reasonable that there is no significant difference between days following weekends or holidays and weekdays. Both Hartge Boat Yard and Kent Narrows Marina are smaller than the previous four marinas and serve a mixture of pleasure craft and workboats. The size of the marinas and the mixture of vessels may explain why no significant difference exists between the two time periods. In addition, the sample size was small for these two facilities. 20 Table 6 - Comparison of Fecal Coliform Levels in Marina Waters on Days Following Weekends or Holidays with Days During the Week Location 7 Vj . T.--7. Significant- 4 at the 5% level Seward's Point Marina 2.36 1.93 .43 + Piney Narrows Marina 2.29 2.04 .25 + and Yacht Club County Marina 2.43 1.92 .51 Cedar Point Marina 2.23 1. 73 .50 + Hartge's Boat Yard 2.64 2.24 .40 Kent Narrows Marina 2.31 1.90 .41 -------------------------------------------------------------- Ze fecal coliform mean-in marina on days following weekends or holidays x fecal coliform mean in marina on days during the week + = significant; not significant A gradient of increasing densities of fecal coliform is evident from the mouth to the rear of Piney Narrows Marina and Seward's Point Marina. The loglo means of the fecal coliform MPN/100 ml for Piney Narrows and Seward's Point Marinas was higher at the stations at the rear of the two marinas than at the stations at the center or the mouth. (Table 7) Table 7 - Log,O Means for Fecal Coliform Densities in Piney Narrows Marina and Sewards Point Mar6za Mouth of Middle of Rear of Marina Marina Marina Piney Narrows Marina 1.74 2.19 E-30 eward's Point Marina 1.80 2.00 2.37 21 The waters in the marinas and in Kent Island Narrows are classified as shellfish harvesting waters. Kent Island Narrows is extremely important to the shellfish industry as it is sheltered from winter winds and may be worked when rough waters keep harvesting boats off the open Bay. Bacteriological water quality standards set forth by the National Shellfish Sanitation Program (NSSP) for shellfish harvesting waters were applied to all sampling stations in the marinas and the Kent Island Narrows. The fecal coliform standard for this program as applied in Maryland requires that no samples can exceed a median of 14 fecal coliform MPN/100 ml and that no more than 101yo of the samples can exceed 49 fecal coliform MPN/100 ml when using the 3-tube decimal dilution test. Median values for fecal coliform MPNs were calculated for all marina and channel sampling stations over the two year period. When the National Shellfish Sanitation Program standard was applied to this data, no sampling station met the required standard for shellfish growing waters. (Table 8) This data supports the need to restrict the waters in Kent Island Narrows for shellfish harvesting. Table 8 - Station Compliance with National ShelyiA Sanitation P@rogram Standardsfor Fecal Col!form Number of Median Percentage Geometric Station Samples (MPN/100ml) Over 49 Mean 22A 29 93 52 63 Seward's 22B 22 93 59 100 Point Marina 22C 22 240 77 234 23A 28 84 54 55 Piney Narrows 23B 22 240 77 155 Marina and Yacht 23C 22 240 77 200 Club 25A 29 93 62 county marina Kent Narrows 25B 29 43 48 =72 marina - Hartge's Boat 14C 2-2 460 73 2673 Yard 13C 23 93 61 Cedar Point 89 Marina 22 49 23 25 22 Kent 23 49 23 29 26 Island 24 47 43 38 39 Narrows 25 48 20 31 25 22 Bacteriological water standards set forth by the Water Resources Administration for water contact recreation were applied to all sampling stations in Kent Island Narrows and the Marinas. This standard requires that fecal coliform densities in recreational waters be less than a log mean of 200 MPN/100 ml. If the bacterial water, quality exceeds a log mean of 200 MPN/100 ml, water quality will be considered acceptable only if a detailed sanitary y and evaluation discloses no significant public health risk in the use of the waters. When this standard was applied to the log means of fecal coliform, MPNs at all stations in Kent Island Narrows, the water quality was surve satisfactory for recreational use. Two stations located within marinas, however, exceeded the water contact recreation standards. The geometric mean for fecal coliform at Station 22C in the Tear of Seward's Point Marina was 234 and the geometric mean for Station 14C in Hartge Boat Yard was 264. Both of these sampling locations are recessed from the Kent Island Narrows and are probably subject to poor flushing. Station 23C located in the rear of Piney Narrows Marina had a fecal coliform geometric mean of 2 00 which is the maximum permitted level. 23 DISCUSSION Total coliform and fecal coliforin are indicator organisms used to assess the bacteriological quality of water. Presence of the coliform group, particularly fecal coliform, is an indicator of the possible contamination of water with sewage since these organisms may be found in the enteric tract of warmblooded animals including man. Since many boats are equipped with toilet facilities which discharge raw or partially treated wastes to boating waters, it is reasonable to assume that where large concentrations of boats are found elevated levels of total and fecal coliform, will be present in the waters. Ten sampling stations were established in six marinas to study the effect boating activity may have on total and fecal coliform levels in marina waters. Data from these stations was compared to data generated at sampling stations located outside the marinas in Kent Island Narrows, the Chester River and Prospect Bay. The study spanned a two-year period. Statistical analysis of the data has shown a significantly higher level of total and fecal coliforin in marina waters than in the Kent Island Narrows channel, the Chester River or Prospect Bay. Investigation has eliminated seafood processing houses or on-shore waste disposal systems as sources of total or fecal coliform. in the marina basins. The higher levels of indicator organisms in marina waters are apparently the result of human wastes discharged from the boats. This finding of elevated coliform densities in the marinas is consistent with the findings of other investigators. The marina study by the Virginia Military Institute Research Laboratory for the Virginia Department of Health (1973), stated that the total coliform and fecal coliform MPN in boat mooring areas were significantly higher than that obtained from bacteriological tests on surrounding water. This was attributed to the lack of adequate flushing action because of the recessed location of many harbor areas.8 Lear, Marks, and Schmincke (1966) in their evaluation of coliform contribution from pleasure boats in estuarine waters found that the data indicated a slight increase and persistence of coliform with the congregation of pleasure yachts. ' I Seward's Point Marina and Piney Narrows Marina and Yacht Club are located in dredged basins off the main channel of the Narrows. There is a marked increase in bacteriological loading from the mouth to the rear of these marinas. This may be related to the configuration of the marina basin and the lack of good tidal flushing. Weekends and holidays are usually periods of high activity at marinas populated with pleasure boats. Many people never leave their boat slips and often spend the entire weekend or holiday in one location. As a result of this practice, wastewater may be discharged overboard creating an excessive bacteriological loading on surface waters. The effect of weekend boating activity on marina waters was examined by comparing fecal coliform levels in the waters of a marina on a day following a weekend or holiday to levels in marina waters on weekdays. Seward's Point Marina, Piney Narrows Marina and Yacht Club, and Cedar Point Marina are large marinas which cater to pleasure craft. All 3 marinas had significantly higher fecal coliforin values in their marina waters on days following holidays or weekends. The higher level of coliform. in Cedar Point Marina is especially significant since this marina lies off from Marshy Creek, where there is little commercial or residential development. The County Marina which services only commercial fishermen's work boats showed no significant difference between weekends and weekdays, This is consistent with the six day work week of commercial fishermen. The two smaller marinas, Hartge Boat Yard and Kent Narrows Marina, serve a mixture of pleasure craft and commercial workboats. The lack of a statistically significant difference between fecal coliforin levels in their waters on weekdays and days following weekends or holidays may be a function of the mixture of vessels served, the small size of the marinas or the small sample size. 8. Department of Health, Commonwealth of Virginia, Marina Regulations (House Document No. 8), Richmond, Virginia, 1973. 9. Lear, Marks@ and Schmincke, Evaluation of Coliform Contribution by Pleasure Boats, CB-SRBP, Technical Paper No. 10, Middle Atlantic Region, FWPCA, 1966. 24 The finding of elevated fecal coliform levels in marina waters following weekends or holidays is consistent with the findings of Wagenet and Lawrence. Their eight month study to determine if recreational use had a marked effect upon the quality of impounded water showed that as recreational attendance increased on Friday and Saturday and peaked on Sunday so did fecal coliform MPN levels. 10 The Maryland State Department of Natural Resources, Water Resources Administration, published a report in 1965 concerning the bacteriological levels at a major Chesapeake Bay boating-bathing site during the Independence Day holiday. An increase in coliform levels over the holiday weekend followed by a decrease on the subsequent weekdays was a major finding of the report. 10. R. J. Wagenet and C. H. Lawrence, Recreational Effects on Bacteriological Quality of an Impounded Water Supply, journal of Environmental Health, Volume 37, No. 1, 1974. 11. A. E. Sanderson, Jr., and Thomas C. Hopkins, Jr.. Coliform and E. Coli Bacteria Counts at a Ma.lor Chesapeake Bav Boating@ Bathing Site During the Independence Day Holiday Period, Annapolis, Maryland, 1965. 25 CONCLUSION Bacteriological data generated from a two-year study has shown a significantly higher total coliform and fecal coliform loading at sampling stations located in the marinas in Kent Island Narrows. Total coliform and fecal coliform levels at sampling stations in the Kent Island Narrows and at stations in the Chester River and Prospect Bay were significantly lower than those associated with marinas. A gradient of increasing densities of fecal coliform is evident from the mouth to the rear of Piney Narrows Marina and Seward's Point Marina. Marinas located in dredged basins off the main channel may not experience good tidal flushing therefore coliform. organisms may accumulate and persist in the extremities of these marinas. A significant relationship exists between the time of the week and the fecal coliform levels in the waters of the 3 large marinas. These marinas serve primarily pleasure craft. Fecal coliform densities on days following weekends and holidays were significantly higher than fecal coliform densities on weekdays in Seward's Point Marina, Piney Narrows Marina and Cedar Point Marina. Greater weekend activity associated with pleasure craft appears to be responsible for higher weekend and holiday fecal coliform densities. The waters in Kent Island Narrows and the surrounding marinas did not meet the National Shellfish Sanitation Program standard for shellfish harvesting waters. Results from all stations monitored in the two year period exceeded the standard. The waters of Kent Island Narrows were not acceptable for shellfish harvesting. Bacteriological standards for Class I Recreational Waters were applied to the fecal coliform results from all sampling stations in the study. In Seward's Point Marina, water quality in the backwaters of the marina exceeded bacteriological standards for recreational vehicles. Water quality in Hartge Boat Yard also exceeded the standard. In Piney Narrows Marina, the fecal coliform level in the backwaters of the marina reached the maximum allowable limit for recreati, waters. The recessed location of these three marinas apparently hinders adequate flushing action resulting in elevated fecal coliform levels. Based on the data in this report, marinas in the Kent Island Narrows are significant contributors toward bacterial loading in surface waters. 26 References W. C. Boicourt, Measurement of Tides and Currents in Kent Island Narrows, Open File Report No. 11, Chesapeake Bay Institute, Johns Hopkins University, February, 1978. Official Record, Division of Water Supplies, Water and Sewage Control Programs, Environmental Health Adminis- tration, Department of Health and Mental Hygiene. Maryland Department of Natural Resources, Water Resources Administration, Chester River Basin Water Quality Management Plan, Annapolis, Maryland, 1976. E. E. Geldreich, Sanitary Significance of Fecal Coliform in the Environment, U.S. Department of the Interior, November, 1966. R. Steel and J. Torrie, Principles and Procedures of Statistics, McGraw Hill Book Company, Inc., New York, 1960. Department of Health, Commonwealth of Virginia, Marina Regulations (House Document No. 8), Richmond, Virginia, 1973. Lear, Marks, and Schmincke, Evaluation of Col@form Contribution by Pleasure Boats, CB-SRBP, Technical Paper No. 10, Middle Atlantic Region, FWPCA, 1966. R. J. Wagenet and C. H. Lawrence, Recreational Effects on Bacteriological Quality of an Impounded Water Supply, journal of Environmental Health, Volume 37, No. 1, 1974. A. E. Sanderson, Jr., and Thomas C. Hopkins, Jr., Col@form and E. Coli Bacteria Counts at a Major Chesapeake Bay Boating-Bathing Site During the Independence Day Holiday Period, Annapolis, Maryland, 1965. 27 I APPENDIX I 28 SEWARD'S POXNT %WINA Date of Station 22A Station 22B Station 22C Sample Fecal Fecal Fecal Collection Tide Coliform Coliform Coliform Coliform Coliform Coliform 4/16/74 --- 4/23/74 Ebb --- --- --- 4/24/74 Ebb 4/29/74 Flood --- --- --- --- --- --- 5/9/74 Ebb 93 23 43 43 240 15 5/21/74 Ebb --- --- --- --- --- -- 5/29/74 Flood 460 43 1100 9.1 460 150 6/4/74' Ebb --- --- --- --- --- --- 6/17/74 Ebb 240 43 -460 460 460 460 7/8/94 Ebb --- --- --- --- --- -- 7/22/74 Ebb 1100 ISO 240 93 240 240 7/29/74 Flood 1100 93 240 240 2400+ 2400+ 8/13/74 Flood 240 93 240 93 1100 460 8/21/74 Ebb 93 43 93 23 460 23 9/16/74 Ebb 460 39 93 23 240 43 10/21/74 Ebb 240 240 2400+ 2400+ 240 240 10/22/74 Ebb --- --- --- --- --- --- 11/12/74' Flood 460 93 240 93 240 93 12/4/74 M)b 2400+ 1100 2400+ 1100 2400+ 460 1/6/75 Flood -- --- --- --- --- --- 1/13/75 Ebb 460 240 1100 1100 --- 460 2/5/75 Flood 460 460 1100 1100 460 460 4/7/75 Flood 93 93 93 43 460 93 4/14/75 Ebb --- --- --- --- --- --- 4/16/75 Ebb 240 9.1 43 9.1 150 39 5/7/75 Ebb 460 43 240 15 1100 1100 5/13/75 Ebb --- --- --- --- --- --- 5/26/75 Ebb 2400+ 460 2400+ 120 2400+ 2400+ 6/4/75 Flood 240 9.1 460 93 460 93 6/17/75 Flood --- 7/21/75 F-bb --- 7/30/75 Flood 460 240 460 43 2400+ 1100 8/4/75 240 93 240 240 460 240 9/2/75 Flood 2400+ 1100 2400+ 75 2400+ 2400+ 9/16/75 Flood --- --- --- --- --- --- 10/8/75 Ebb --- --- --- --- --- --- 10/16/75 Ebb 1100 93 2400+ 43 460 43 10/28/75 Ebb --- --- --- --- --- --- 11/17/75 Flood 1/21/76 Ebb 1/26/76 Flood 23 3.6 1/29/76 Flood 210 93 2/3/76 Mb 2400+ 43 --- --- 2/4/76 Ebb 1100 23 --- --- --- 2/11/76 Flood 1100 3.6 --- 2/18/76 Ebb 240 43 3/2/76 Ebb --- --- 3/15/76 Flood 240 <3 4/20/76 F-bb --- --- 5/17/76 Ebb --- Coliform and Fecal Coliform exDressed as ml PINEY NARROWS MARINA Date of Station 23A Station 23B Station 23C Sample Fecal Fecal Fecal Collection Tide Coliform Coliform Coliform Coliform Coliform Coliform 4/16/74 --- --- --- 4/23/74 Ebb 4/24/74 Ebb --- --- 4/29/74 Flood --- --- --- 5/9/74 Ebb 43 43 240 23 460 43 5/21/74 Ebb --- --- --- --- --- --- 5/29/74 Flood 460 93 240 43 240 240 6/4/74 Ebb --- --- --- --- --- --- 6/17/74 Ebb 460 93 2400+ 460 460 240 7/8/74 Ebb --- --- --- --- --- --- 7/22/74 Ebb 1100 1100 2400+ 240 460 43 7/29/74 Flood 1100 240 2400+ 460 2400+ 2400+* 8/13/74 Flood 460 75 240 240 240 240 8/21/74 Ebb 460 93 460 75 240 93 9/16/74 Ebb --- --- 460 93 1100 93 10/21/74 Ebb 240 240 2400+ 2400+ 460 240 11/12/74 Flood 93 93 240 240 2400+ 1100 12/4/74 Ebb 2400+ 460 2400-4- 460 1100 240 1/6/75 Flood --- --- --- --- --- --- 1/13/75 Ebb 43 23 150 93 93 43 2/5/75 Flood 93 93 93 93 240 21 4/7/75 Flood 460 23 460 93 460 93 4/14/75 Ebb --- --- --- --- --- 4/16/75 Ebb 43 3.6 43 15 93 9.11 5/7/75 Ebb 240 240 1100 240 160 240 5/13/75 Ebb --- --- --- --- --- --- 5/26/75 Ebb 2,(00+ 1100 2400+ 1100 2400+ 460 6/4/75 Flood 460 43 460 240 460 460 6/17/75 Flood --- --- --- --- --- --- 7/21/75 Ebb --- --- --- --- --- --- 7/30/75 Flood 1100 120 460 240 2400+ 11-00 8/4/75 43 23 23 9.1 1100 460 9/2/75 Flood 2400+ 43 2400+ 1100 24004- 2400+ 9/16/75 Flood --- --- --- --- --- --- 10/8/75 Sbb --- --- --- --- --- --- 10/16/75 Ebb 2400+ 150 1100 39 2400+ 210 10/28/75 Ebb --- --- --- --- --- -- 11/17/75 Flood --- 1/21/76 Ebb --- --- 1/26/76 Flood 43 23 1/29/76 Flood 460 9.1 --- 2/3/76 Ebb 2400+ 9 .1 --- 2/4/76 Ebb 2400+ 93 2/11/76 Flood 2400+ 3.6 2/18/76 Ebb 1100 9.1 --- --- 3/2/76 Ebb --- --- .3/15/76 Flood 150 3.6 4/20/76 Ebb --- --- 5/17/76 F-bb --- --- --- Coliform and Fecal Coliform expressed as HPN/100 *nl HARTGES BOAT WORKS Date of Station 14C Sample Fecal collection Tide Coliform Coliform 4/16/74 Flood --- 4/23/74 Ebb --- --- 4/24/74 Ebb --- 4/29/74 Ebb --- --- 5/9/74 Ebb 1100 460 5/21/74 Flood --- --- 5/29/74 Flood 1100 460 6/4/74 Flood --- -- 6/17/74 Flood 1100 460 7/8/74 Ebb --- --- 7/22/74 Ebb 460 43 7/29/74 Flood 460 460 8/13/74 Flood 240 43 8/21/74 Ebb 240 13 9/16/74 Ebb 2400+ 240 10/21/74 Ebb 2400+ 1100 10/22/74 Ebb --- -- 11/22/74 Flood 460 460 12/4/74 Ebb 2400+ 240 1/6/75 Flood --- --- 1/13/75 Ebb 2400+ 2400+ 2/5/75 Flood 1100 1100 4/7/75 Flood 240 240 4/14/75 Ebb --- --- 4/16/75 Ebb 23 23 5/7/75 Ebb 1100 110Q 5/13/75 Ebb --- --- 5/26/75 Ebb 2400+ 1100 6/4/75 Flood 210 23 6/17/75 Flood --- 7/21/75 Ebb --- --- 7/30/75 Flood 43 23 8/4/75 Slack 2400+ 1100 9/2/75 Flood 2400+ 150 9/16/75 Flood --- --- 10/8/75 Ebb --- --- 10/16/75 Ebb 2400+ 2400+ 10/28/75 Ebb --- --- 11/17/75 Flood --- 1/21/76 Ebb 1/26/76 Flood 1/29/76 Flood 2/3/76 Ebb --- --- 2/4/76 Ebb 2/11/76 Flood 2/18/76 Ebb 3/2/76 Ebb 3/15/76 Flood 4/20/76 Ebb 5/17/76 Ebb Coliform and ?ecal Cali-form expressed as MPN/100 ml COUNTY MARINA Date of Station 25A Sample Fecal Collection Tide Coliform Coliform 4/16/74 4/23/74 Ebb --- 4/24/74 Ebb 4/29/74 Ebb --- --- 5/9/74 Ebb 240 93 5/21/74 Ebb -- --- 5/29/74 Flood 460 23 6/4/74 Ebb --- --- 6/17/74 Ebb 2400+ 2400+ 7/8/84 Ebb --- --- 7/22/74 Ebb 1100 460 7/29/74 Flood 2400+ ISO 8/13/74 Ebb .240 240 8/21/74 Ebb 1100 460 9/16/74 Ebb 460 93 10/21/74 Ebb 93 93 10/22/74 Ebb -- --- 11/12/74 Flood 43 is 12/4/74 Ebb 1100 240 1/6/75 Flood --- --- 1/13/75 Flood 460 is 2/5/75 Flood 240 240 4/7/75 Flood 150 ISO 4/14/75 Ebb --- 4/16/75 Ebb 93 <3 5/7/75 Flood 460 3.6 5/13/75 Ebb --- --- 5/26/75 Ebb 2400+ 240 6/4/75 Flood 1100 460 6/17/75 Flood --- --- 7/21/75 Ebb --- --- 7/30/75 Flood 1100 460 8/4/75 2400+ 1100 9/2/75 Flood 2400+ 2400+ 9/16/75 Flood --- --- 10/8/75 Ebb --- --- 10/16/75 Ebb 2400+ 210 10/28/75 Ebb --- --- 11/17/75 Flood 1/21/76 Flood --- --- 1/26/76 Flood 23 9.1 1/29/76 Flood ISO 9.1 2/3/76 Ebb 2400+ 9.1 2/4/76 Ebb 2400+ 39 2/11/76 Flood 2400+ <3 2/18/76 Ebb 240 93 3/2/76 Ebb --- --- 3/15/76 Flood 460 9.1 4/20/76 Ebb --- --- Coliform and Fecal Coliform expressed as MPN/100 ml CEDAR POINT MARINA Date of Station 13C Sample Fecal collection Tide Coliform Coliform 4/16/74 Flood --- --- 4/23/74 Ebb 4/24/74 Ebb --- 4/29/74 Ebb --- --- 5/9/74 Ebb 460 93 5/21/74 Ebb --- --- 5/29/74 Flood 1100 43 6/4/74 Flood --- --- 6/17/74 Flood 1100 93 7/8/74 Ebb -- --- 7/22/74 Ebb 460 460 7/29/74 Flood 2400+ 43 8/13/74 Flood 1100 23 8/21/74 Ebb 1100 75 9/16/74 Ebb 2400+ 43 10/21/74 Ebb ..240 240 10/22/74 Ebb -- --- 11/12/74 Flood 240 23 12/4/74 Ebb 2400+ 460 1/6/75 Flood --- --- 1/13/75 @Ebb 460 240 2/5/75 Flood 43 43 4/7/75 Flood 460 93 4/14/75 Ebb 4/16/7S Ebb 23 9.1 5/7/75 Ebb .150 14 5/13/75 Ebb --.Z --- 5/26/75 Ebb 2400+ 1100 6/4/75 Flood 460 93 - 6/17/75 Flood --- --- 7/21/75 Ebb --- --- 7/30/7S Flood 2400+ 93 8/4/75 460 93 9/2/75 Flood 2400+ 460 9/16/75 Flood --- --- 10/8/75 Ebb --- --- 10/16/75 Ebb 460 240 10/28/75 Ebb --- --- 11/17/75 Flood 1/21/76 Ebb --- 1/26/76 Flood --- 1/29/76 Flood 2400+ 43 2/3/76 Ebb --- --- 2/4/76 Ebb 2/11/76 Flood --- --- 2/18/76 ebb 3/2/76 Ebb 3/15/76 Flood 4/20/76 Ebb 3/171/76 Zbb @oiifor-n and Fecal Coliform expressed -as MPN/100 ml KENT NARROWS MARINA Date of Station 25B Sample Fecal Collection Tide Coliform Coliform 4/16/74 4/23/74 Ebb 4/24/74 Ebb 4/29/74 Flood 5/9/74 Ebb 75 23 5/21/74 Ebb 5/29/74 Flood 1100 150 6/4/74 Ebb --- 6/17/74 Ebb 460 460 7/3/74 Ebb --- --- 7/22/74 Ebb 2400+ 23 7/29/74 Flood 2400+ 240 8/13/74 Ebb 460 240 8/21/74 Ebb 75 23 9/16/74 Ebb iloa 43 10/21/74 Ebb 1100 1100 10/22/74 Ebb --- --- 11/12/74 Flood 240 43 12/4/74 Ebb 2400+ 2400+ 1/6/75 Flood --- --- 1/13/75 Flood 460 93 2/5/75 Flood 150 43 4/7/75 Flood 240 93 4/14/75 Ebb --- --- 4/16/75 Ebb 9-3 3.6*- 5/7/75 Flood 2400+ 460 5/13/75 Ebb --- --- 5/26/75 Ebb 2400+ 240 6/4/75 Flood 1100 ISO 6/17/75 Flood --- 7/21/75 Ebb --- --- 7/30/75 Flood 120 75 8/4/75 1100 460 9/2/75 Flood 2400+ 1100 9/16/75 Flood --- --- 10/8/75 Ebb --- --- 10/16/75 Ebb 240.0+ 43 10/28/75 Ebb --- --- 11/17/75 Flood --- 1/21/76 Flood -- --- 1/26/76 Flood 23 3.6 1/29/76 Flood 210 23 2/3/76 Ebb 2400+ 43 2/4/76 Ebb 2400+ 9.1 2/11/76 Flood 290 9.1 2/18/76 Ebb 460 15 3/2/76 Ebb --- --- 3/15/76 Flood 240 23 4/20/76 Ebb --- --- Coliforin and Fecal Coliform expressed as MPN/100 ml KENT *4ARROWS CHANNEL STATIONS Date of station 24 Station 25 Samp@e Fecal Fecal Collection Tide Coliform Coliform Colifor2 Coliform 4/4/74 Ebb --- --- --- 4/16/74 43 43 9.1 <3 4/23/74 Ebb 93 is 93 7.3 4/24/74 Ebb 23 9.1 75 @.6 4/29/74 Flood 23 23 240 23 5/9/74 Ebb 43 is 93 21 5/21/74 Ebb 93 93 23 <3 5/29/74 Flood 2400+ 93 460 93 6/4/74 Ebb 150 43 75 43 6/17/74 Ebb 1100 210 460 39 7/8/74 Ebb 1100 14 93 3.6 7/22,*74 EbLb 43 9.1 23 3.6 7/29/74- Flood 1100 43 460 150 8/13/74 Ebb 93 93 240 240 8/21/74 Ebb 240 93 460 20 9/16/74 Ebb 240 23 93 3.6 10/21/74 Ebb 460 460 93 93 10/22/74 Ebb 460 ISO 23 23 11/12/74 Flood 460 240 140 240 12/4/74 Ebb 2400+ 460 1100 240 1/6/75 Flood 23 <3 3.6 3.6 1/7/75 Flood --- --- --- --- 1/13/75 Ebb 460 75 460 93 2/5/75 Flood 460 460 2400+ 9.1 4/7/75 Flood 150 23 2400+ 2400+. 4/14/75 Ebb 9.1 3.6- 9.1 <3 4/16/75 Ebb 23 23 43 <3 4/22/75 Flood --- --- --- --- 5/7/75 Ebb --- --- U00 28 5/13/75 Ebb 93, 23 43 23 5/26/75 Ebb 6/4/75 Flood @40 23 U30 1100 6/17/75 Flood 1100 9.1 460 <3 6/18/75 Ebb --- --- --- --- 7/21/75 Ebb 460 240 240 9.1 7/30/75 Flood 1100 21 43 3.6 8/4/75 240 93 93 9.1 9/2/75 Flood 2400+ 240 2400+ 240 9/8/75 Ebb --- 9/16/75 Flood 2/40 43 1.50 20 9/29/75 -Flood 10/7/75 -Ebb 10/8/75 Ebb 43 43 23 3.6 10/16/75 Ebb 2400-4- 21 460 ISO ..10/28/75 Ebb ISO* 150 460 .460 11/3/75 Il/.17/75 F load IS() 75 460 240 1 ''21/76 43 <3 , E:bb 43 9.11 1/26/76 Flood 43 7.3 23 9_1 1/29/76 Flood 460 93 U00 _23- 2/3/76 Ebb 1100 43 2400+ 11,00 2,4/76 Ebb 2400+ 23 40 0 + 75 15 2/11/76 Flood 2400+ 43 2400+ 2/18/76 Ebb 43 23 460 15 3/2/76 Ebb 93 3.6 11 )0 3.6 3/15/76 Flood 460 9.1 ISO 9.1 4/20/76 Ebb Z400+. 93 1100 23 5/17/76 Ebb --- --- --- Coliform and Fecal Coliform expr-issed as MPN/100 ml KENT NARROWS CHANNEL STATIONS Date of Station 22 Station 23 Sample Fecal Fecal Collection Tide. Coliform Coliform Coliform Coliform 4/4/74 Ebb --- --- --- --- 4/16/74 Flood 75 23 240 240 4/23/74. Ebb 23 <3 93 15, 4/24/74 Ebb 23 3.6 23 9.1 4/29/74 Flood 93 23 240 43 5/9/74 Ebb 150 9.1 93 is 5/21/74 Ebb 23 9.1 240 -240 5/29/74 Floodt 240 93 240 43 6/4/74 Ebb 43 43 93 15 6/17/74 Ebb 23 3.6 43 43 7/8/74' Ebb 240 <3 93 23 7/22/74 Ebb 23 9.1 23 1.6 7/29/74 Flood 93 43. 240 93 8/13/74 Ebb 23 3.6 240 240 8/21/74 Ebb 210 93 ISO 43 9/16/74 Ebb 240 9.1 43 <3 10/21/74 Ebb 93 9.1 43 43 10/22/74 Ebb 9.1 9.1 93 9.1 11/12/74@ Flood 43 15 23 23 12/4/7-4 Ebb 460 43 2400+ 1100 1/6/75 Flood 43 <3 43 <3 1/7/75 Flood --- --- --- 1/13/75 Flood 460 23 240 9.1 2/5/75 Flood 43 7.3 93 93 4/7/75 Flood 240 23, 460 23 4/14/75 Ebb 23 <3 23 <3 4/16/75 Ebb 43 <3 23 <3 4/22/75 Flood --- --- --- --- 5/7/75 Ebb 1100 93 460 93 5/13/75 Ebb 43 - 23 23 3.6 5/26/75 r-bb --- --- --- --- 6/4/75 Flood 240 240 240 240 6/17/75 Flood 150 15 210 9.1 6/18/75 Ebb --- --- --- --- 7/21/75 Ebb 460 - 23 ISO 9.1 7/30/75 Flood 460 93 93 9.1 8/4/75 1100 460 1100 240 9/2/75 Flood 2400+ 93 2400+ 93 9/8/75 Ebb --- --- --- --- 9/16/75 Flood 43 43 240 43 9/29/75 Flood --- --- --- 10/7/75 Ebb --- --- --- --- 10/8/75 Ebb 93 23 23 23 10/14/75 Flood --- --- --- --- 10/16/75 Ebb 2400+ 43 240 is 10/28/75 Ebb 240 240 1100 1100 11/3/75 --- --- --- 11/17/75 Flood 93 43 240- 240 1/13/76 Flood --- --- --- 1/21/76 Ebb 23 3.6 23 3.6 1/26/76 Flood 23 9.1 23 9.1 1/29/76 Flood 460 240 460 3.6 2/3/76 Ebb 2400+ 15 '400+ 15 2/4/76 Ebb 2400+ 290 2 4 0 0 -@- 150 2/11/76 Flood 2400+ 290 2400+ ISO 2/18/16 Ebb 1100 9.1 150 7. 3 3/2/76 Ebb 460 9.1 .240 3.6 3/15/76 rlood 240 9-.1 43 5/20/76 Ebb ISO 93 4-1) 3.6 5/10/76 Ebb --- --- --- --- 5/17/76 Ebb 43 2.3 93 23 Coliform and fecal coliform express4d as MPN/100 ml I I I .1 1.1 11 I I I I I I II -j 11 I I Bromwell Press, Inc., Baltimore, MD I I ' . IN I 3 6668 00000 8864 I I