Description:

Located along a bend in the James River, this project required intense planning and coordination in order to replace an existing outfall pipe during a 48-hour shutdown of the WWTP. In addition to navigating a shutdown, the work had to take place during an opportune time when the tide and weather were conducive for in water work. Ahead of the shutdown, Maverick crews fused the 8” HDPE outfall pipe, installed RCP pipe segments along the pipe alignment for ballast, and excavated around the active outfall to expose the tie in point. Once the plant was shut down, the HDPE outfall pipe was floated out into the river and pulled through the RCP pipe segments and then connected to the existing pipe main. A thrust block and cleanout were installed followed by numerous lifts of compacted fill. Once the plant was turned back on, crews completed the project by armoring the shoreline with Class II rip rap.

​

Challenges:

• The work had to take place during an extreme low tide that occurred during the daytime hours. In addition, the 2-day forecast had to show no wind as the location was prone to significant wave action due to the upstream and downstream fetch.

• During the outage, crews discovered that the existing pipe was not C-900 as shown on the contract documents and was instead SDR-35. Maverick worked closely with the engineer to develop a solution which entailed a fernco coupling and thrust block installation as the line required restrained joints.

​

Value: $90,100