Gulfstream Natural Gas/HDD Design and Construction
Using a horizontal directional drilling (HDD) method to protect an archaeological site and surroundings from damage during pipeline installation.
GeoEngineers provided expert geotechnical engineering and horizontal directional drilling (HDD) design and construction consulting services for three crossings along the proposed Phase III expansion of the current Gulfstream Natural Gas pipeline system in Florida. The HDD installations were part of 34 miles of new 30-inch-diameter pipeline.
The three HDD crossings the team designed were located within five miles of each other, near the eastern shore of Lake Okeechobee. Their crossing lengths were 2,700, 1,985 and 1,650 feet.
- Gulfstream chose the HDD construction method because its pipeline needed to cross canals and an archeological site without disturbing the surroundings. Drilling underneath the sites enabled the company to limit the environmental impact of the pipeline construction.
- GeoEngineers evaluated subsurface conditions up to 100 feet at the three HDD crossings.
- The GeoEngineers’ design team analyzed where drilling would start and end on either side of the canals and archeological site, how much force HDD construction equipment could bear, and how well the pipe would curve when pulled back through the hole underground.
- At each HDD crossing, GeoEngineers documented HDD construction contractor actions during drilling of the initial hole underground, enlarging of the hole, and pulling the pipe back through the hole.
- GeoEngineers recommended the HDD construction contractor keep the pipe from floating in drilling fluid by choosing a method to control buoyancy, such as filling the pipe with water. This reduced the possibility of damaging the pipe coating while pulling it back through the drilled hole.
- GeoEngineers’ onsite observations and detailed daily reporting enabled Gulfstream to dispute well over $100,000 in unwarranted construction claims. GeoEngineers completed its work under budget.
- Efforts to reduce drilling fluid leakage at the sites protected the surrounding environment.
- GeoEngineers staff was on site for the duration of the project and communicated concerns directly to Gulfstream, helping reduce construction delays.