Bolivar Ohio Seepage Barrier & Rehabilitation Projects

Bolivar Dam, Muskingum River Basin, Ohio Major Rehabilitation Project

The Bolivar Dam project consisted of the construction of a seepage barrier approximately 4,500 ft. (1,372 meters) in length and a maximum depth of 144 ft. (44 meters) through the upstream slope of the dam embankment along the left abutment. Drilling and grouting was performed along an alignment approximately 300 ft. (91 meters) in length by 60ft. (18 meters) average depth in the left abutment of the dam from the end of the seepage barrier to near the emergency spillway was also required.

GFA provided quality control (QC) testing which consisted of:

  • Mix design testing of proposed SBBM for hydraulic permeability of not less than 1×10-6 and unconfined compressive strength.
  • Exploratory borings to confirm underlying sand stone depth utilizing continuous flight auger, SPT sampling, rock coring and roto sonic sampling methods.
  • Constructed on site testing laboratory and curing facilities and achieve ACOE validation prior to start of seepage barrier
  • Pre-placement sampling and testing of the SBBM for permeability and compressive strength.
  • Post placement testing of SBBM for permeability and compressive strength with samples collected from verification borings.
  • Provide Contractor furnished laboratory with calibrated and maintained equipment for ACOE QC testing

Challenges encountered included, heavy rain events in the spring during exploratory drilling on the slope of the levee which required temporary access roads and stabilization to be added in order to complete the borings. Additionally, extremely high hydraulic permeability test results from pre-placement samples in the range of 8×10-9 resulting in delays in the reporting. GFA coordinated with our client and the ACOE to allow higher testing pressures and reduce duplicative testing requirements in order to get the reporting of the samples on time and meet the project schedule.