WEST SACRAMENTO LEVEE EVALUATION PROJECT DRAFT PROBLEM IDENTIFICATION REPORT April 2008 2365 Iron Point Road, Suite 300 Folsom, CA 95630 DRAFT Problem Identification Report 1. Introduction.......................................................................................................................... 1 1.1 Overview............................................................................................................................................. 1 1.2 Purpose .............................................................................................................................................. 1 1.3 Project Goals and Report Objectives ................................................................................................. 2 1.4 Study Area Description....................................................................................................................... 2 1.5 Background and History ..................................................................................................................... 5 1.6 Interagency Coordination ................................................................................................................... 8 1.7 Previous Studies................................................................................................................................. 8 2. General Levee Evaluation Criteria ...................................................................................... 9 2.1 USACE Levee Design Criteria............................................................................................................ 9 2.2 The Reclamation Board.................................................................................................................... 10 2.3 Requirements for FEMA Certification ............................................................................................... 10 2.4 Site-Specific Criteria ......................................................................................................................... 12 3. Existing Conditions ............................................................................................................13 3.1 General Levee Layout ...................................................................................................................... 13 3.2 Levee Performance .......................................................................................................................... 16 3.3 Water Surface Elevations ................................................................................................................. 17 3.4 Utilities .............................................................................................................................................. 17 3.4.1 Utility Inventory.......................................................................................................................... 17 3.4.2 Utility Assessment ..................................................................................................................... 19 3.5 Environmental Resources ................................................................................................................ 20 3.5.1 Land Cover Description............................................................................................................. 20 3.5.2 Threatened and Endangered Species ...................................................................................... 21 3.5.3 USACE Vegetation Policy ......................................................................................................... 21 4. Levee Deficiency Analysis .................................................................................................23 4.1 Types of Deficiency .......................................................................................................................... 23 4.1.1 Seepage .................................................................................................................................... 23 4.1.2 Slope Stability............................................................................................................................ 23 4.1.3 Seismic Vulnerability ................................................................................................................. 23 4.1.4 Erosion ...................................................................................................................................... 23 4.1.5 Freeboard .................................................................................................................................. 23 4.1.6 Geometry................................................................................................................................... 23 4.2 Geotechnical Engineering Evaluation............................................................................................... 24 4.2.1 Levee Seepage Analysis........................................................................................................... 24 4.2.2 Levee Slope Stability Assessment ............................................................................................ 27 4.2.3 Seismic Vulnerability ................................................................................................................. 29 4.3 Erosion Assessment......................................................................................................................... 32 4.4 Levee Height Evaluation................................................................................................................... 34 4.4.1 Freeboard Evaluation ................................................................................................................ 34 4.4.2 Wind-Wave Analysis ................................................................................................................. 43 4.5 Levee Geometry Evaluation ............................................................................................................. 44 5. Summary .............................................................................................................................46 5.1 Conclusions ...................................................................................................................................... 46 5.2 Recommendations............................................................................................................................ 53 6. References...........................................................................................................................54 XrThp hrGrrr@hyhvQ wrp 6 vy!' DRAFT Problem Identification Report TABLES TABLE 1.4.1 – CURRENT AND PREVIOUS REACH NAMES TABLE 2.1.1 – USACE LEVEE DESIGN CRITERIA TABLE 3.2.1 – P.L. 84-99 SITES TABLE 3.4.1.1 – UTILITY COMPANY CONTACT INFORMATION TABLE 4.2.1.1 – SEEPAGE SUMMARY FOR SACRAMENTO RIVER WEST NORTH LEVEE TABLE 4.2.1.2 – SEEPAGE SUMMARY FOR SACRAMENTO BYPASS LEVEE TABLE 4.2.1.3 – SEEPAGE SUMMARY FOR YOLO BYPASS LEVEE TABLE 4.2.1.4 – SEEPAGE SUMMARY FOR PORT NORTH LEVEE TABLE 4.2.1.5 – SEEPAGE SUMMARY FOR PORT SOUTH LEVEE TABLE 4.2.1.6 – SEEPAGE SUMMARY FOR DWSC WEST TABLE 4.2.1.7 – SEEPAGE SUMMARY FOR DWSC EAST TABLE 4.2.1.8 – SEEPAGE SUMMARY FOR SACRAMENTO RIVER WEST SOUTH LEVEE TABLE 4.2.1.9 – SEEPAGE SUMMARY FOR SOUTH CROSS LEVEE TABLE 4.2.2.1 – SLOPE STABILITY SUMMARY FOR SACRAMENTO RIVER WEST NORTH LEVEE TABLE 4.2.2.2 – SLOPE STABILITY SUMMARY FOR SACRAMENTO BYPASS LEVEE TABLE 4.2.2.3 – SLOPE STABILITY SUMMARY FOR YOLO BYPASS LEVEE TABLE 4.2.2.4 – SLOPE STABILITY SUMMARY FOR PORT NORTH LEVEE TABLE 4.2.2.5 – SLOPE STABILITY SUMMARY FOR PORT SOUTH LEVEE TABLE 4.2.2.6 – SLOPE STABILITY SUMMARY FOR DWSC WEST TABLE 4.2.2.7 – SLOPE STABILITY SUMMARY FOR DWSC EAST TABLE 4.2.2.8 – SLOPE STABILITY SUMMARY FOR SACRAMENTO RIVER WEST SOUTH LEVEE TABLE 4.2.2.9 – SLOPE STABILITY SUMMARY FOR SOUTH CROSS LEVEE TABLE 4.2.3.1 – SEISMIC SUMMARY FOR SACRAMENTO RIVER WEST NORTH LEVEE TABLE 4.2.3.2 – SEISMIC SUMMARY FOR SACRAMENTO BYPASS LEVEE TABLE 4.2.3.3 – SEISMIC SUMMARY FOR YOLO BYPASS LEVEE TABLE 4.2.3.4 – SEISMIC SUMMARY FOR PORT NORTH LEVEE TABLE 4.2.3.5 – SEISMIC SUMMARY FOR PORT SOUTH LEVEE TABLE 4.2.3.6 – SEISMIC SUMMARY FOR DWSC WEST TABLE 4.2.3.7 – SEISMIC SUMMARY FOR DWSC EAST TABLE 4.2.3.8 – SEISMIC SUMMARY FOR SACRAMENTO RIVER WEST SOUTH LEVEE TABLE 4.2.3.9 – SEISMIC SUMMARY FOR SOUTH CROSS LEVEE TABLE 4.3.1 – EROSION SITE IDENTIFICATION TABLE 5.1.1 – REACH SUMMARY XrThp hrGrrr@hyhvQ wrp 6 vy!' DRAFT Problem Identification Report FIGURES FIGURE 1 – STUDY AREA FIGURE 2 – WEST SACRAMENTO BASIN LEVEE REACHES FIGURE 3 – RECENT LEVEE RECONSTRUCTION FIGURE 4 – SACRAMENTO RIVER BASIN FLOOD MANAGEMENT SYSTEM FIGURE 5 – WEST SACRAMENTO NORTHERN BASIN – LEVEE REACH STATIONING FIGURE 6 – WEST SACRAMENTO SOUTHERN BASIN – LEVEE REACH STATIONING FIGURE 7 – TYPICAL LEVEE CROSS SECTION FIGURE 8 – CURRENTLY IDENTIFIED DEFICIENCIES ON SACRAMENTO RIVER WEST NORTH LEVEE FIGURE 9 – CURRENTLY IDENTIFIED DEFICIENCIES ON SACRAMENTO BYPASS AND YOLO BYPASS LEVEES FIGURE 10 – CURRENTLY IDENTIFIED DEFICIENCIES ON PORT NORTH AND PORT SOUTH LEVEES FIGURE 11 – CURRENTLY IDENTIFIED DEFICIENCIES ON DWSC WEST, DWSC EAST, AND SOUTH CROSS LEVEE FIGURE 12 – CURRENTLY IDENTIFIED DEFICIENCIES ON SACRAMENTO RIVER WEST SOUTH LEVEE GRAPHS GRAPH 1 – FREEBOARD EVALUATION OF SACRAMENTO RIVER WEST NORTH LEVEE GRAPH 2 – FREEBOARD EVALUATION OF SACRAMENTO BYPASS LEVEE GRAPH 3 – FREEBOARD EVALUATION OF YOLO