FEMA Emergency Flood Control Structure Repairs


Diamond D provided emergency civil engineering construction services to the Yolo County Flood Control and Water Conservation District to repair the West Adams Canal and Bridge, Moore Siphon, Gibson Bypass and Alder drop flood control structures that were damaged by high water flows during the winter of 2005/2006. The repairs were funded by the Federal Emergency Management Agency (FEMA) and performed over an accelerated seven week schedule. Some repair tasks were competitively bid with twenty-four response times and others were awarded and started immediately as emergency response tasks. Diamond D also provided turnkey design-build services for repairs that required engineering analysis.

Tasks performed to repair and/or reinforce damaged elements including demolishing and reconstructing concrete slabs, wingwalls and head walls, installing precast concrete structures, placing geotextile fabric, rip-rap and grout, placing and compacting imported clay soils, filling scour holes with lean concrete, and removing sediment.

Even though in–channel construction tasks were conducted on an emergency basis, they were performed without generating turbidity or negatively impacting the environment by using "green" construction techniques and specialized equipment such as Komatsu CD 110 low –ground pressure carriers. The repair tasks also included environmental benefits, such as enhanced fish habitat.


  • Constructed reinforced concrete slab, retaining walls and reinforced concrete wingwall extensions anchored to existing structures with dowels and epoxy
  • installed precast concrete turnout, pipe and stilling well
  • Placed 100 tons of 12 Inch rip – rap
  • Placed geotextile fabric
  • Grouted rip-rap
  • Placed and compacted 1,600 cubic yards of imported clay soils
  • Removed 300 cubic yards of sediment
  • Filled scour holes with lean concrete

Owner: Yolo County Flood Control District

Contract Value: $667,763.91 Completion Date: June 20, 2006

Reference: Available Upon Request