Herbert Hoover Dike Rehabilitation Project Reach 1 Cutoff Wall Gap Closure

The work for this project included constructing approximately 2200 linear feet of cutoff wall in Reach 1 of the Herbert Hoover Dike embankment, where gaps were left around water control structures S-308, S-352, S-351, and Torry Island Bridge. Cutoff wall construction shall consist of conventional cutoff wall and jet grout cutoff wall. 

GFA Services

GFA International, Inc. is performing a wide variety of quality control (QC) services. This QC testing consisted of:

  • Mix design testing of proposed SBBM for hydraulic permeability of not less than 1 x 10-6 and unconfined compressive strength
  • Pre-construction survey of existing facilities
  • Vibration control plan creation and implementation
  • Vibrating wire piezometer installation with real time geo-net instrumentation and monitoring 
  • Exploratory drilling
  • Soil cement and soil cement bentonite QC testing for UCS, viscosity, permeability and unit weight 
  • Staged verification coring and testing
  • Falling head and rising head permeability testing
  • Borehole geophysical logging – optv camera, bore deviation and CCTV camera
  • Testing of embankment and MSE wall materials
  • Vibration monitoring
  • Rotary sonic drilling and sampling for QC testing of mixed materials