Project Highlights

• Replace gravity sewers
• Collection system improvements
• Reduce combined sewer overflows

Project Description

The Richmond Sanitary District recently finished constructing over $6 million in collection system improvements, which involved replacing and rerouting aged gravity sanitary sewers with new twenty-four (24) to thirty-six (36) inch diameter pipe using a combination of open-cut and trenchless methods.  The project is an important part of Richmond’s goal to reduce combined sewer overflows (CSOs) into the East Fork Whitewater River.

Richmond has significant elevation changes throughout the city, which presented several design and construction challenges. Those challenges include:

• The design and construction of a dual-barrel siphon under the East Fork Whitewater River, which conveys flow from the West Side Interceptor to Richmond’s deep rock East Side Interceptor.
• Steep slope stabilization after the construction of the dual-barrel siphon.
• Open-cut construction across the East Fork Whitewater River.
• Protection of a county bridge utilizing pinning via soil nails prior to the construction of the sanitary sewer.
• Bore and jack sewer installation under a Norfolk Southern railroad bridge.
• Ensuring that the proposed improvements associated with the RSD’s CSO Long Term Control Plan will be successful via design-level collection system hydraulic modeling.