The Design-Build team of Garney Construction and Dewberry Engineers was engaged by Hampton Roads Sewer District to design and build a force main crossing the James River in Newport News, Virginia. Brierley Associates was brought on by Dewberry as geotechnical specialists and provided on-site assistance during the trenchless installation.
Late in the evening on May 2, 2024, the HDD was successfully completed beneath the Newport News Shipping Channel after almost 24 hours over two days of continuous pipe pullback operations. The operation commenced early on May 1 with tugs towing the 5700 feet of fused 42-in HDPE pipe across the James River from its moored location near the south shore. The pipe was then carefully pulled aboard the pipe handling barge using rollers and crane cradles until it was in position at the pipe pusher assembly just above the previously installed 66-in steel casing pipe. About 150 ft of pipe was then advanced into the casing to test all equipment. Pipe ballasting using river water began from a 6-in HDPE pipe and was continuously monitored using load cells to ensure that the 42-in pipe remained filled with water at all times during the pullback.
Once the pipe pusher was reassembled and tested, pipe pullback operations started at about 10 pm. The pipe was advanced in approximately 31-foot sections, initially descending to the bottom tangent at an Elevation of -160 ft before eventually beginning the ascent back to the surface. Brierley’s Jim Williams was onsite with the drillers throughout this process, carefully checking actual pullback loads for each pipe joint against the estimated loads from our design calculations. At approximately 8 pm on May 2, the barrel reamer at the front of the pipe string emerged from the casing onshore in Newport News, 5614 linear feet from the barge, indicating the successful world record completion of the HDD.