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Tetra Tech Certification Geographic Focus. San Bernardino County (CA) Riverside County (CA) Ventura County (CA) Washington DC City of Kent (WA) City of Massillon (OH) City of Aurora (CO) Papio NRC/Omaha (NE). The FEMA Program. PROGRAMMATIC PMS. PM34 Certify Levees.
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Tetra Tech Certification Geographic Focus • San Bernardino County (CA) • Riverside County (CA) • Ventura County (CA) • Washington DC • City of Kent (WA) • City of Massillon (OH) • City of Aurora (CO) • Papio NRC/Omaha (NE)
The FEMA Program PROGRAMMATIC PMS PM34 Certify Levees PM 43 PAL Program PM 45 PAL Note TECHNICAL PMS PM52 Decertified Levee Mapping PM51 Non-levee Embankments PM 53 Expiring PALs PM63 Technical Review Process NFIP Regulations: 44 CFR 65.10
FEMA Procedural Memorandums • PM-34 • Issued August 2005 • Identify all Levees on Map • Responsibility of Community • PM-43 • Issued March 2007 • Established Provisionally Accredited Levees (PAL) • Allows 2-years to Provide 65.10 Documentation
FEMA Procedural Memorandums • PM-63 • Issued September 2010 • Levee Accreditation Checklist • Tiered Review process • Upstream and Downstream tie-in • Tie-in to High Ground • natural high ground? FEMA Certification Comments
NFIP Regulations (44CFR65.10) • Design Criteria • Freeboard • Closures • Embankment Protection • Stability • Settlement • Interior Drainage • Operations Plan • Maintenance Plan http://www.gpo.gov/
Freeboard • BASE Freeboard • 3’ (riverine) • 2’ (coastal) • ADDITIONAL Freeboard • +1’ at constrictions (bridges) • +0.5’ upstream end • Exceptions (R&U) • Hydrologic Record • Hydraulic Sensitivity • Geotechnical (coming) freeboard
Levee Station Equivalent Record Length (year) Top of Levee Elevation (feet) 100-year Water Surface Elevation (feet) Actual Freeboard (feet) CNP for a 100-year flood event Minimum Freeboard (feet) Minimum Top of Levee Elevation (feet) CNP2 for a 100-year flood event LOWER DEVORE LEVEE 200+98.68 71 1,894.68 1,886.41 8.27 99.98% 3 1,889.41 95.7% MILL CREEK LEVEE 197+93.11 52 2283.22 2277.81 5.41 91.03% 3 2,280.81 88.9% 191+92.95 52 2266.68 2254.87 11.81 100.00% 3 2,257.87 80.7% 79+94.76 52 1821.46 1813.46 8.00 99.95% 3 1,816.46 79.7% DEMENS LEVEE 17+26.23 45 2124.15 2112.83 11.32 99.85% 3 2,115.83 90.1% 5+62.00 45 2007.55 2002.13 5.42 100.00% 3 2,005.13 92.9% Freeboard
Closures “All openings must be provided with closure devices”
Closures “All openings must be provided with closure devices” Spillways Side drain pipes – options? Channels / canals FEMA Certification Comments
Geotechnical • Stability • USACE EM 1110-2-1913 • Settlement • USACE EM 1110-2-1904
Interior Drainage • Joint Probability Analysis • River stage • Local runoff
Operation Plan • Officially Adopted Plan • Responsibility – name/title • Any Manual Operation? • Flood Warning • Implementation Plan FEMA Certification Comments
Maintenance Plan FEMA Certification Comments • Vegetation Policy • USACE ETL 1110-2-571 - Guidelines for Landscape Planting and Vegetation Management at Levees, Floodwalls, Embankment Dams, and Appurtenant Structures Figure 1: Levee Section - Basic
Without Levee Analysis What does it mean?
Without Levee Analysis What does it mean? When will we know what it means?
Levee Evaluation and Rehabilitation Questions & Answers
PAL Certification Timeline • 2005 • COE/Tt Robles Dam Modifications • 1949t • Matilija Dam • 2009 • VC/Tt Phase I Evaluation • FEMA/HDR FIS • 1958 • Castaic Lake • 2011 • COE/Fugro Inspection (Spring) • VC/KC 30% CdSJ design (July) • VC/Tt CTP Study (Nov) • 2000 • COE/BOR Study • Matilija Removal 1950 2000 2005 2010 • 2010 • VC/COE/Tt Develop Study Paths • VC/Tt Stop-log Maintenance Review • VC/TtMeiners Oaks / Live Oak Design Review • 1958 • Robles Diversion Dam • 1970 • NFIP Regs