San Antonio Water System W-6 Upper Segment Main Project

San Antonio, Texas

Stiver Engineering provided key services as part of the largest and most complex sanitary sewer improvement project that the San Antonio, Texas Water System (SAWS) has ever undertaken. The project involves replacing a deteriorating, 5-mile-long pipeline, known as the “W-6 Upper Segment” main, that serves approximately 500,000 residents in the San Antonio area. The replacement pipe will be designed to last 100 years.

Stiver’s work included designs for steel casing, bore pit/access shaft, and grouting plans along with a concrete thrust block analysis. Buckling and jacking calculations were provided for the 36-inch casing pipe. Stiver also helped the contractor with a plan to grout fill around the 8-inch and 12-inch PVC carrier pipes inside the 36-inch casing. A custom concrete thrust block was provided to the contractor to help with the installation of the 36-inch casing pipe. Stiver Engineering provided the support/restraint design for the 60-inch and 104-inch diameter Hobas carrier pipes along with the buoyancy calculations and grout pour designs.