Stiver Engineering provided numerous services for capital improvements to a 108- inch-diameter water line running from Aldine Westfield Road to Willis Street in Houston, Texas. We created shoring and portal designs for launch and receiving shafts — some as deep as 31 feet — using sheet pile and soldier piles, wale sets, steel plates, timber lagging, and other methods. Stiver also created trench safety designs for installation, special shoring requirements with trench boxes, steel plates and soldier piles, and steel casing designs.

The Joes Creek Interceptor project in Dallas involves 8,370 linear feet of 60-inch excavated diameter tunnel that will house 36-inch HOBAS carrier pipe. There are 20 shafts (ranging from 21 to 48 vertical feet in depth), and ground conditions include sand, sand with gravel, sandstone, sandy clay, shaley clay, and shale (Eagle Ford). Stiver Engineering provided steel casing pipe calculations for 8 runs. We also created designs for various sizes of shoring pits using sheet piling and wale sets, as well as designs for a 32-foot-diameter liner plate and ring beam shaft at various locations and TBM face pressure calculations.

As part of a major infrastructure project at the Schoharie Reservoir in Gilboa, New York, Stiver Engineering provided a variety of services for a low-level outlet designed to release water downstream into Schoharie Creek to facilitate dam maintenance and emergency response, mitigate flood risk, and enhance downstream habitat for fish and wildlife. The work includes construction of a 9.5-foot diameter micro-tunnel at a depth of 160 feet. Stiver provided designs for the gate shaft as well as analysis of the steel jacking frame for the tunnel machine and steel pipe. We also provided trench safety designs, thrust block designs, steel pipe casing designs, anchor bolt attachment designs, and a structural review of the Herrenknecht tunnel launch seal and pipe break frames, among other services.

The city of Houston replaced a 42-inch diameter water line that stretched from West Belfort Avenue to Bissonnet Street along Braes Forest Drive. Stiver Engineering provided steel casing and thrust block designs for the installation of the water line. Calculations were provided for a total of 14 tunnels that varied in depth and length. The casing runs were used to determine the jacking loads that were going to be transferred to the thrust blocks.

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.