In 2010, the Construction Division at the New Orleans District of USACE had a Quality Control concern at Lilly Bayou, a large flood control weir just north of Baton Rouge, Louisiana. The specifications on a 5 to 1 concrete slope were to be no more than 1/8 of an inch of deviation in any 10 feet. They didn’t think the contractor met the specifications but couldn’t prove it by conventional survey methods. DS&A was requested to perform a test scan which, when completed settled the question once and for all. The deviations in the surface were obvious in the point cloud. DS&A was subsequently awarded a task order to scan the whole structure and provide specific CAD and ascii deliverable’s to the Corps engineers. Along with this data DS&A also delivered “color mapped” pdfs as well as contours to assist the engineers in determining the specifications.
Read more: Laser Scanning on a Flood Control Structure