Tunnel Boring for WHCRWA’s Major Water Supply Project

DEC uses large tunnel boring machines (TBMs) to excavate miles of tunnels for large-diameter water lines for the West Harris County Regional Water Authority (WHCRWA).

The Suzzann TBM is working on Surface Water Supply Project (SWSP) Segment B3 in Harris County. This TBM will excavate approximately 4.4 continuous miles of 126-inch-diameter tunnel for a 96-inch-diameter water line.

The Sheryl TBM (named in honor of late Right-of-Way Manager Sheryl Bookman) is working on SWSP Segment B1/B2 in Harris County. She will excavate approximately 1.8 miles of 132-inch-diameter tunnel for mainly a 96-inch-diameter waterline. Overall, Segment B1/B2 will have about 10 miles of 96-inch-diameter waterline, with some dug by other TBMs.

WHCRWA is one of the largest water supply programs in the region. DEC manages the $1.8 billion program in coordination with more than 120 municipal utility districts, cities and regulatory agencies. DEC leads a team of internal and external professionals tasked with designing and building more than 100 miles of pipelines and three booster pump stations to deliver more than 150 million gallons a day of surface water to the service area’s growing population.