Horizontal Directional Drilling
Designing around obstacles
There are always obstacles encountered when routing a pipeline. Sometimes, significant and/or sensitive obstacles; like large streams, rivers, water bodies, extensive wetlands, railroads, or major highways, where conventional open cut, or jack-and-bore pipeline installation methods are not practical or permissible. In those cases, a Horizontal Directional Drilling (HDD) method will be necessary to route the pipeline below the surface obstacles.
Each pipeline obstacle and situation is unique; so before an HDD contractor can unleash their boring equipment; the areas on either side of the obstruction need to be evaluated to determine feasibility of exit and entry points for the bore. Steep slopes, proximity to buildings or structures, geology, landowner requirements, etc. can all affect the length and depth of the HDD bore design.
Our engineers pay special attention to develop a geometric design of the HDD bore to take into account the entry and exit angles, pipe size, and minimum radius and depth required beneath the surface obstruction. This design needs to prioritize the safety and preservation of the surface obstruction, while remaining mindful that unnecessary HDD length and depth will increase construction costs. Pipe stringing and pullback areas will also be identified behind the bore access points, to allow the HDD contractor room to operate.
From civil and environmental services to mechanical pipeline design, we provide HDD design services to fit your project and get you around obstacles to a finished pipeline. We have experience conducting both desktop and field constructability reviews to help identify site constraints and design parameters. Lastly, regardless of what HDD service(s) we’re providing, we work alongside both you and the HDD contractor to ensure that any questions or concerns associated with the design and installation are considered and addressed, keeping you informed and confident in your project.
horizontal directional drilling services include:
- Feasibility & cost analysis
- Site selection/constructability review
- Permitting (environmental, state highway, railroad)
- Geometric design of HDD (exit & entry angles, minimum radius, etc.)
- Pipe string pull-back areas & workspace analysis
- Coordination of geotechnical investigation for HDD bore design
- HDD bore profiles
- Pipe stress calculations
- Hydrostatic test, purge, & blow-down plans