The Clackamas 20-inch Reroute was a partnering project that the Barnard Pipeline's estimating team began working on in 1999. Crossing the Clackamas River near Carver, Oregon, the pipeline lateral was designed to serve nearly all of the natural gas needs for the state of Oregon west of the Cascade Range. An 800-foot section of the pipeline had to be lowered 20 feet (below scour depth). The challenge was to develop a work plan that was constructible, safe, and within budget, yet would ensure that the in-service existing 20-inch pipeline would not be compromised in any way.  Because of groundwater at 7 feet and unstable soil conditions, two shoring systems were implemented: modified/engineered trench boxes; and H-pile driven 40 feet with a 16,000-pound vibratory hammer and installation of steel sheets. The engineered trench shoring was designed to allow the water to accumulate in the shored trench.