Raw Water Delivery System – Construction Phase Services

The Brushy Creek Regional Utility Authority (BCRUA) Raw Water Delivery System delivers a permanent raw water supply from Lake Travis to the cities of Cedar Park, Leander, and Round Rock, Texas. The system carries an ultimate capacity of 142 million gallons per day and includes two 10-ft diameter steel-lined deep-water intake assemblies, an 8,800-ft intake tunnel with a 96-in finished inside diameter and cast-in-place concrete liner, a 2,600-ft transmission tunnel with a 78-in finished inside diameter, and a raw water pump station with a wet well shaft extending approximately 300 ft below grade.

Subsurface conditions consist of alluvium overlying the Glen Rose Formation. The project presented significant geo-structural challenges, including deep shaft construction in both marine and land environments, underwater connections between the intake assemblies and the intake tunnel beneath Lake Travis, and the complexity of coordinating TBM and roadheader construction methods across multiple tunnel and shaft components simultaneously.

Brierley Associates was contracted directly by SAK Construction, LLC to provide construction phase services. The team developed support design calculations for the initial support of the Main Shaft, Suction Chamber, Intake Tunnel, and Transmission Tunnel. Brierley also produced design support calculations for the Lake Tap Connections, Suction Chamber brow support, and Starter/Tail Tunnel brow support, and conducted tunnel assessments and numerous site visits throughout construction.