HDD Culvert Cleaning Proves Effective

By Jeff Griffin, Senior Editor | March 2010 Vol. 65 No. 3

Most travelers are unaware of the complexity of engineering and constructing modern highways and streets, and many of the most critical elements that make a roadway safe and able to withstand heavy traffic for years into the future are not readily apparent.

Culverts play a vital role by carrying water under sections of roadways to prevent flooding during periods of heavy rainfall and reduce erosion of soil formations beneath and around the road's surface.

Most culverts are relatively short in length, but often are buried quite deep. They are of various sizes and shapes, including round, elliptical and box configurations of steel, HDPE and PVC pipes and box shaped structures of concrete. But whatever the shape and material used, culverts are an integral part of a highway's road/drainage interface.

Critical to culvert performance is keeping them free of blockages. Access often is a challenge and excavating the roadway to clear obstructions is a disruptive and costly solution. Therefore, culvert cleaning is an often neglected aspect of highway maintenance.

Bob Harr, founder and owner of Harr Technologies, Kasilof, AK, believes many culverts in the United States never have been cleaned which has resulted in damages to the structures themselves, as well as roads, ditches and other property, and can potentially cause serious injuries.

"One of the main reasons cities and highway and transportation departments have not properly maintained culverts is due to the lack of efficient and effective culvert cleaning methods," says Harr. "Open cutting a road, jetter trucks, backhoes and cables, are methods used to clean culverts and each method has shortcomings."

Harr has developed special downhole tools and a method of employing horizontal directional drilling (HDD) equipment for accessing and cleaning culverts that, he says, can access and clean the structures faster and at less costs than conventional methods. Harr holds patents for the downhole tools and method of using them. The Harr cleaning procedures are in use in the United States and other parts of the world, but many transportation officials responsible for maintaining culverts remain unfamiliar with the benefits.

High-profile job
To date, the system's trenchless culvert showcase project has been on Alaska's James Dalton Highway. The road has received wide attention from the television program, Ice Road Truckers, on the History Channel.

Basic components of Harr's culvert cleaning system are: