In February 2025, Brownline USA surveyed the pilot bore for a long HDD crossing in Corpus Christi, TX. This crossing under the busy ship channel was completed using the intersect method.
New water line under ship channel
The port of Corpus Christi is the fifth largest port in the USA and the largest in oil exports. To provide capacity for more and larger ships, the ship channel will be widened and deepened. Several existing utilities will have to be moved to accommodate this. This included the installation of a 24” water line below the ship channel and an 8” gas line parallel to it. In addition to the ship channel, a wetlands area called Tule Lake was crossed.
The pipelines were installed with horizontal directional drilling. HDD contractor HardRock Infrastructure installed the 24” water line by drilling a 1886 m / 6189 ft crossing below the ship channel. To carry out the pilot bore with the highest accuracy, Brownline USA was called in to survey the job with the Drillguide Gyro Steering Tool.
Intersect crossing using Drillguide GST and Radar
This crossing was carried out using the intersect method, with entry points on either side of the ship channel. At the southern entry point at Tule Lake, the vertical curve was combined with a 17° horizontal curve, creating a compound curve. By relying on the most accurate gyro steering tool in the world, both drills were kept on track as the ship channel was crossed.
As both drill heads approached each other, Brownline’s Radar technology was activated to measure the relative distances between them. These measurements made it possible to connect the two boreholes together smoothly and efficiently. A smooth intersect is very important to ensure an efficient pullback of the steel pipeline.
The use of Brownline USA’s services in this trenchless project resulted in a highly accurate and efficient pilot bore, and a safe installation of the new water line.