Three Rivers Levee Improvement Program

MBK Engineers continues to work with the Three Rivers Levee Improvement Authority (TRLIA) on their program to repair the levees of Reclamation District (RD) 784. TRLIA was formed in 2004 to develop, finance, and implement a program to provide increased flood protection to RD 784, the most populous area in Yuba County. Prior to TRLIA’s formation, MBK worked with the Yuba County Water Agency on levee improvements first investigated under Water Act of 2000 grants. MBK has provided the hydraulic analysis and design for the levee repair and environmental restoration program. MBK also provides overall program management and design management over an extensive team of geotechnical consultants, civil engineering consultants, real estate specialists, and environmental consultants. The program for RD 784 has consisted of a series of Problem Identification Reports to provide geotechnical evaluation of the levees, followed by Design Reports, environmental documents to meet CEQA requirements, and finally plans and specifications for construction. TRLIA currently has a four phase program of construction to bring all RD 784 levees to a 200-year level of protection. Phases 1 to 3 have been completed and Phase 4 initiated. Contracts have been completed for over 10.5 miles of levee repairs at a cost of over $84,000,000. Repairs have consisted of raising levees, flattening oversteep slopes, installing slurry cutoff walls, installing stability and seepage berms, installing relief wells, reconstructing pumping stations, and constructing a two mile setback levee along the Bear River. Included with the Bear Setback Levee was environmental restoration of 600 acres of agricultural land in the floodplain to riparian habitat. Extensive coordination has occurred with the Corps of Engineers and FEMA to ensure that levee repairs will be accredited by FEMA. MBK has coordinated potential Section 104 Credits with the Corps and a Section 408 permit for levee alteration. Several Reclamation Board encroachment permits were obtained for the levee repairs. The TRLIA program is scheduled to complete Phase 4 of its construction program in 2008 with construction of a six mile setback levee and associated restoration along the Feather River. MBK is coordinating with DWR with the objective of obtaining Proposition 1E funds for construction of this important improvement to the Sacramento River Flood Control System.