PITTSBURGH, PA – July 30, 2010 – In early 2010, Nicholson Construction Company finished the construction of a double-line grout curtain at the Howard A. Hanson Dam in western Washington State. This high profile project was completed under a very strict schedule and heavy public scrutiny.
Howard A. Hanson Dam, built in 1962, is an earth embankment dam. The dam embankment is 235 feet high and 675 feet long. The composition of the right abutment foundation is partially bedrock and unconsolidated alluvial and landslide material. The right abutment has leaked since the dam became operational. A leak in January 2009 filled the reservoir higher than ever, prompting the U.S. Army Corps of Engineers (USACE) to reclassify Hanson Dam as “unsafe” with an “urgent and compelling” need for immediate action.
[Editor] Click through for the rest of this press release from GeoPrac.net Premier Sponsor Nicholson Construction Company [/Editor]