DA Smith was commissioned in 2020 by the US Department of Transportation Federal Highway Administration (FHWA), Central Federal Lands Highway Division to conduct exploratory drilling on the existing Upper and Lower Kings River highway bridges located in Kings Canyon National Park, Highway 180, California. ODEX drilling was required through the sand and granite boulder sediments comprising the Kings River channel for the purpose of evaluating a deep foundation refitting option.
A total of 1,154 feet was drilled in 11 holes, with the deepest hole reaching 115 feet. Holes were drilled through the both the bridge deck and roadway abutments. SPT sampling was conducted on 5-foot intervals. Downhole flowing sands required the use of a special cuttings capture and diversion system to avoid sediment contamination in the river. DA Smith controlled highway traffic while drilling with an automated traffic signal system. Careful coordination with the FHWA, National Park Service, and regional vendors allowed logistical challenges posed by the site’s remote mountain location to be overcome, resulting in a successful and efficient drilling campaign.