In February 2024, Brownline USA made a key contribution to the installation of a force main under James River, Virginia. Using our Drillguide GST and Radar technology, our client Huxted Trenchless was able to complete a land-to-barge intersect in Newport News, VA. The project broke a world record: never before was a 42” HDPE line installed with this length.
The aim of this HDD was to install a force main under the James River, as part of a large project to greatly improve the quality of water in the area. A pumping station, to be constructed in Newport News, will pump wastewater through the force main, across the river and to a treatment plant in Suffolk, VA. The water can then be treated and released into the river, or it can undergo advanced treatment to meet the quality standards for drinking water.
95% of the trajectory under water
To carry out this crossing, a barge was set up in the James River to allow for HDD equipment, and crews travelled per boat to this jobsite. A large diameter casing was installed on both entry points with a 16” / 400 mm centralizer casing inside.
With roughly 95% of the trajectory under water, gyro equipment was essential in order to survey this crossing. To ensure directional accuracy in the soft soil and a proper depth under the river, the pilot drill was completed using the most accurate guidance system available: Brownline’s Drillguide Gyro Steering Tool. By keeping the pilot drill on its planned trajectory with as little deviation as possible, it minimizes the pipe stress for the 42” HDPE line that would be installed.
Radar intersect deep below the riverbed
During the entirety of the pilot drill, annular pressure was carefully monitored using Brownline’s PWD (Pressure-While-Drilling) module. This helped prevent inadvertent returns under the riverbed.
At the intersect zone, the relative separation between the two drill heads was measured quickly and accurately using Brownline’s Radar. This allowed crews to determine the ideal curve to join the boreholes as smoothly and effortlessly as possible. This efficient intersect was completed 30 m / 100 ft below the riverbed.
After the pilot drill was completed, the client could continue their operations, which resulted in the successful pullback of 5658 ft / 1725 m of 42” HDPE pipe – a world record length for this material and diameter! Brownline USA is proud to have contributed to the pilot phase of this remarkable achievement.
Want to know how our tools can aid your HDD project? Contact us!