Old Alabama Road 48 “Water main relocation
Roswell, Ga.
BEST PROJECT
Sent by: Ruby-Collins Inc.
Owner: City of Atlanta, Watershed Management Department
Principal Design Firm, Civil Engineer: Management of benchmarks
General contractor: Ruby-Collins Inc.
Successfully relocated 5,200 linear feet of 48 inches. The ductile iron water main along the active roads near the Chattahoochee River took meticulous attention to detail and some outside-the-box sewer thinking.
Ruby-Collins approached this fixed design-build project without disrupting Atlanta’s water supply by moving the water main out of the way of a freeway project. Operating on busy roads and near a popular park required meticulous coordination to keep traffic flowing and workers safe.
Project requirements included the continued operation of Atlanta’s vital water supply from a jointly operated Fulton County water source north of the city, though the project team says in the filing that the greatest challenges facing the project revolved around its proximity to the Chattahoochee and the raid. of water in the excavations at the diversion point, line stop and link to the existing line. Divers were needed to carry out the work safely after failures of existing facilities. The proximity to the river also caused hydraulic intrusion problems that required grout injection.
Photo courtesy of Ruby-Collins Inc.
The team also evaluated the engineering of a proposed hole-and-stake section under an existing 8-foot by 12-foot box culvert into a 72-inch culvert. mine tunnel by hand.
Overcoming challenges such as lead times of up to two years for large-diameter pipes, the armored excavation required constant monitoring against water ingress, which led the team to collaborate with a subcontractor specialized in diving to successfully complete the project.
Ruby-Collins prioritized several in-house and third-party safety training sessions, including Excavation and Confined Space Competency courses, as well as 10-hour OSHA sessions for more than two dozen workers. A third party was also brought in to inspect the project’s traffic control measures, which had little or no impact on residents, even with flyovers and other underground work. An OSHA inspection through the National Trench Emphasis program resulted in no recommendations, citations or return inspections for the project, which had zero recordable incidents or lost time accidents during 38,500 hours of work.