Construction crews out to tame Ross Point
June 12, 2008 · Updated 9:52 AM
"Just as mass quantities of groundwater has been drained away from the Ross Point hillside on State Route 166, so will its notoriety.At least Steve Lowell thinks so.The geotechnical engineer for the state Department of Transportation said the $1.09 million fix, buttressing the dry hillside with rock, should be finished by early November, allowing the highway between downtown Port Orchard and Gorst to reopen to its customary heavy traffic.Scoccolo Construction, the Seattle-based company that contracted with the state for the Ross Point project, confirmed work is moving along as scheduled.Better still, once the project reaches completion, engineers expect slides wont occur again for a long time, if ever.It would be highly unlikely that another severe slide would occur, Lowell said. Worst case scenario, wed have to add more drains to the hillside or more stones along the buttress.Another hill one mile west of Ross Point was similarly braced with rock five years ago. Since then, that hillside hasnt moved, Lowell said.The first step was to get the water out of the slope and keep it out, Lowell explained. To that end, workers angled two plastic drains, both about one and a half inches in diameter, down the length of the hillside. Holes were punctured in the pipes to facilitate draining, Lowell said. Now, any excess water flows down the hill and into the ditch. We know where to put the drains based on studies that determined which areas had high-potential for ground water, Lowell said.Meanwhile, truck-load by truck-load, Scoccolo workers have hauled away about 56,800 cubic yards of material from the bottom of the hill.The dirt is hauled to Ace Paving Co., where its dumped and traded for quarry rock. About six inches in diameter, each rock is pushed up against the bottom of the hillside, further buttressing the soil. Altogether, the rock weighs 43,900 tons.Slides have perennially plagued Ross Point hill because the soils strength was out of balance.Lowell said a soft zoneof clay lays between a top layer of soil, which consists of loose sand and gravel and the lower layer, which consists of compact silts and clays. Add multitudes of water to already weak soil, and its slides galore. Department of Transportation engineers plan to keep a close watch on that hillside even after Scoccolo finishes.Instruments that measure water levels and shifts in the soils are being installed along the hillside. Technicians will monitor soil trends and collect data on water levels as preventive action against possible slides.But Lowell said preventive action wont need to be taken anytime soon. It would be like lightening striking twice, he said."