    [House Document 105-145]
    [From the U.S. Government Publishing Office]

    105th Congress, 1st Session - - - - - - - - - - House Document 105-145

                   NORCO BLUFFS, RIVERSIDE COUNTY, CALIFORNIA

                                   __________

                                 COMMUNICATION

                                      from

      THE ACTING ASSISTANT SECRETARY (CIVIL WORKS), THE DEPARTMENT OF THE
                                      ARMY

                                  transmitting

       A REPORT ON THE PROJECT FOR RIVER BANK EROSION CONTROL AND BLUFF
     STABILIZATION AT NORCO BLUFFS, RIVERSIDE COUNTY, CALIFORNIA, PURSUANT
      TO SECTION 101(b)(4) OF THE WATER RESOURCES DEVELOPMENT ACT OF 1996

       October 6, 1997.--Referred to the Committee on Transportation and
                    Infrastructure and ordered to be printed

                                C O N T E N T S

                                  ----------
                                                                       Page
    Letter of transmittal............................................   vii
    Comments of the Office of Management and Budget..................    ix
    Comments of the State of California..............................     x
    Comments of the Department of the Interior.......................    xi
    Comments of the Federal Emergency Management Agency..............   xii
    Report of the Chief of Engineers, Department of the Army.........     1
    Report of the District Engineer:
        Syllabus.....................................................     7

        I.                          Study Authority..................      9
                                        Authority....................      9
                                        Local Sponsorship............      9
        II.                         Study Purpose and Scope..........     10
        III.                        Prior Studies and Reports........     11
                                        Existing Water Projects......     12
        IV.                         Plan Formulation.................     13
                                        Location and Extent of Study      13
                                     Area.
                                            Location of the Study         13
                                     Area.
                                            Drainage Basin                13
                                     Description.
                                            Physical Setting.........     14
                                            Urban Setting............     15
                                        Problems and Opportunities...     15
                                            Problems.................     15
                                            Opportunities............     18
                                        Planning Objectives and           18
                                     Constraints.
                                            Planning Objectives......     18
                                            Planning Constraints.....     19
                                        Without-Project Conditions...     19
                                            Hydrology................     20
                                            Hydraulics...............     20
                                            Geotechnical.............     24
                                            Economics................     25
                                            Environmental............     28
                                            Recreation...............     34
                                        Formulation of Alternative        35
                                     Plans.
                                        Evaluation of Alternative         42
                                     Plans.
                                            Alternatives Carried          42
                                     Forward.
                                            With-Project Impact           44
                                     Evaluation.
                                        Plan Selection...............     51
                                            Benefits.................     52
                                            Costs....................     56
                                            Benefits/Cost Analysis...     58
                                            System of Accounts.......     59
                                            Additional Evaluation         65
                                     Criteria.
        V.                          Description of the Selected Plan.     66
                                        NED Plan.....................     66
                                            Downstream Impacts.......     68
                                            Real Estate and               69
                                     Construction Easements.
                                            Operation and Maintenance     69
                                            Mitigation Plans.........     70
                                            Recreation Plans.........     71
                                        Locally Preferred Plan.......     71
                                            Downstream Impacts.......     72
                                            Real Estate and               73
                                     Construction Easements.
                                            Operation and Maintenance     73
                                            Mitigation Plans.........     74
    Report of the District Engineer--Continued
                                            Recreation Plans.........     75
                                        Plan Selection...............     76
        VI.                         Plan Implementation..............     77
                                        Study Recommendation.........     77
                                        Cost Allocation..............     77
                                        Institutional Requirements...     77
                                        Environmental Requirements...     78
                                        Views of the Non-Federal          78
                                     Sponsor.
        VII.                        Summary of Coordination, Public       79
                                     Views, and Comments.
        VIII.                       Conclusions and Recommendation...     81
                                        Conclusions..................     81
                                        Additional Study Needs.......     82
                                        Recommendation...............     82
        IX.                         References.......................     83

                                  ----------
    Exhibits:
         1. Regional Map.............................................    85
         2. Erosion Zones............................................    86
         3. Norco Bluffs and Santa Ana River Drainage................    87
         4. Urban Area...............................................    88
         5. Chronological Sequence of Bluff Retreat..................    89
         6. Alternative 1a: Buttress Fill (Imported).................    90
         7. Alternative 1b: Buttress Fill (Cut and Fill).............    91
         8. Alternative 1c: Hilfiker.................................    92
         9. Alternative 1d: Crib Wall/Earthlock......................    93
        10. Alternative 1h: Reinforced Earth.........................    94
        11. Alternative 1i: Concrete Retaining Wall..................    95
        12. Alternative 2b: Soil Cement..............................    96
        13. Alternative 2f: Groins...................................    97
        14. Alternative 5 (Combined 1A & 2B): Locally-Preferred Plan.    98
        15. Alternative 2b: Soil Cement Toe Protection Alternative,
          Plan View..................................................    99
        16. GAlternative 5: Combination of Slope Stabilization and
          Toe Protection Alternative, Plan View......................   100
                                  ----------
    Photos 1 Through 13 Follow Exhibits..............................   101
                                  ----------
    Environmental Impact Statement...................................   109
                                  ----------

          APPENDICES ACCOMPANYING THE REPORT OF THE DISTRICT ENGINEER
                     (Only Appendices F and G are printed)

    Appendix A Written Comments on NOI/NOP
    Appendix B Habitat Evaluation Procedure Analysis
    Appendix C Background Information on Noise Analysis
    Appendix D Fish and Wildlife Reports and Documentation
    Appendix E Endangered Species Act Coordination and Biological
      Assessment
    Appendix F 404b(1) Analysis......................................   240
    Appendix G Finalizing Addendum...................................   245