Stiver Engineering provided the horizontal directional drilling alignment and pulling calculations for a 42’’ inch diameter force main crossing beneath the Houston Ship Channel adjacent to the 69th street wastewater treatment plant. The purpose of the HDD installation was to replace the existing Hedrick Force Main Aerial Crossing. The HDD was approximately 1,000 ft. and was installed to a depth of 100 ft.

Stiver Engineering provided the contractor with an alternate tunneling method for a 6-inch diameter force main.  The alternate design consisted of a horizontal directional drill (HDD) that was 21 ft. beneath an existing railroad.  The pull forces and pipe stresses were analyzed and a profile was delivered to the contractor for construction.

The sewer system in the city of Las Vegas was disjointed and inefficient. Connections to the main sewer line were sporadic, and relief sewers could not adequately intercept flow. To support the City’s waste management, Stiver Engineering provided key design services for the Paradise Whitney Interceptor in Las Vegas.

The project consisted of a 32,000-foot gravity sewer that conveys flow from the Enterprise Water Resource Center and existing interceptors. Over 26,000 lf of trenchless construction were installed, making it one of the most significant trenchless new installation programs in terms of footage undertaken in the United States. The project received an honorable mention for trenches project of the year by Trench Technology.

Stiver Engineering provided a trench excavation safety plan for the open cut sections including fall restraint systems in addition to the trench shoring, bore pits for the tunnel operations, tunnel design, steel casing design, tunnel grouting design and tunnel settlement analysis.

As a part of Memphis’ North Mud Island Interceptor Sewers Project, Stiver Engineering was retained to provide a shoring design for sliplining an existing 120” diameter RCP sewer line with a 110” diameter Hobas pipe.

A custom trench box was proposed with an arch spreader and walers to resist the lateral pressures from weak sandy soils adjacent to the Mississippi River.

Apart from the shoring design, additional cable and rigging calculations were performed for a fall restraint safety line system.

Stiver Engineering provided shoring design services for a 72-inch water line project from Emancipation Avenue to Tuam Street on Clay Street in Houston, Texas. Stiver’s work included secant pile shaft design for the launch and receiving shafts. The shafts are 34 ft ID and 80 ft deep. We also created designs for the breakout structure for the Akkerman TBM.