horizontal directional drilling

Horizontal Directional Drilling or "HDD" is a process or methodology used in pipeline construction to install carrier pipe, conduit or cables underground. In typical pipeline construction, trenching is used to open up ditches whereby pipe is subsequently laid and fastened together to form a finished pipeline. However, there are times when trenching is not ideal, such as when a pipeline is needed under a river, road, highway, railroad crossing, wetland, house, etc. In these situations, and any others where open cutting a ditch is simply not ideal, the horizontal directional drilling or "trenchless" method is deployed to ensure pipe is placed safely underground with minimal disturbance to the above ground structure or element.