Government
Case Study: San Antonio Water System
TTL was asked to provide support to the San Antonio Water System (SAWS) in a dispute between SAWS and the City of San Antonio (COSA). The water and sewer mains on Billings Drive between Prescott Drive and Bay Horse Drive were reconstructed by SAWS in the summer of 2016. The pavements on Billings Drive between Prescott Drive and Bay Horse Drive were reconstructed in the summer of 2017. Shortly after the completion of the pavement reconstruction, longitudinal cracks began to appear on the western and eastern sides of the road.
COSA believed the cracking was a result of settlement in the water line trench backfill, which ran along the western side of the road. TTL developed a study to document the existing conditions of the roadway including locating the cracks using an autonomous aerial vehicle and measuring the elevation changes along the pavement surface. The elevation changes along the pavement surface were measured using a LIDAR survey utilizing a Leica ScanStation P40. Cross sections of Billings Drive were developed at 50-foot intervals. TTL concluded the general conditions observed showed the pavement surface heaved within 3 to 6 feet of the curb line and there was no settlement in the water line trench backfill.