To better understand the long-term effectiveness of in-place scour countermeasures designed using FHWA’s HEC 23 guidance, the FHWA partnered with the U.S. Geological Survey (USGS) to assess the condition of existing scour countermeasures at various bridge sites across the country which had experience significant flooding. From 2014 to 2018, the USGS reviewed countermeasure plans, flood data, and conducted on site surveys using both traditional and newer sonar technologies. The USGS has documented its study findings in two open record reports and a final scientific investigation report. You may find these documents at the following website: https://pubs.er.usgs.gov/publication/sir20195080.
