Sewer Bypass and Replacement in Atlanta, GA

W.L. Hailey Construction contacted Thompson Pump’s Atlanta, GA representative for assistance in a sewer bypass and replacement in a residential area outside the Buckhead business section in Atlanta.

Phase I & II of this project started mid February 2002 and was expected to run until mid-September 2002. The milelong sewer system runs between townhouses, condominiums, and residences. Noise from the construction equipment was a large consideration for W.L. Hailey. The goal was to remove the existing 24-inch sewer line and install a new 42-inch ductile iron gravity sewer line in its place for the full mile.

In addition to the length of sewer that was to be replaced, other considerations were that there was another 10-inch sewer line ran in close proximity to the existing 24-inch sewer line, and that both the 24-inch and 10-inch lines had laterals – sewer lines that branched off from the main line to handle any overflow. The 10-inch sewer lines were operational, but not to the extent of the 24-inch line.

Some city ordinances were obstacles as well: In Atlanta, the noise ordinance stated that pumps were required to have sound levels not in excess of 65 dB(a). Thompson Pump was the only pump manufacturer who could supply the amount of Silent Knight® sound attenuated pumps required for the application and that could meet the city’s noise ordinances. W.L. Hailey also preferred Thompson Pump because of success on previous projects.

Thompson Pump supplied a total of 20 pumps in all with 16 of them being Silent Knight® Trash Pumps in both wet prime and dry prime (compressor-assisted and vacuum-assisted) models; the others were used to evacuate any rain or run-off water from the excavations.

Thompson Pump also supplied approximately 6,000-feet of HDPE (high-density polyethylene) pipe, manifolds, gate valves, and expert service and set-up assistance from the Atlanta and Charleston, SC branches.

A system of three Silent Knight® pumps were strategically situated around each of the desired manholes and each was equipped with the Thompson automatic start/stop system with floats for unattended operation. One of the pumps handled the majority of the pumping, one was a stand-by unit to handle the extra sewage flow from the residents in the surrounding homes, and the third pump was used as back up. Peak flows of up to 9,000-gallons per minute (12,960,000-gallons per day) were experienced.

The residents in the area reported that the pumps did not disturb them when they were at home. One house was as close as 20-feet away from the main manhole and its three-pump system, and reported that they barely could even hear the pumps.

The successful removal and replacement of the sewer line has allowed Thompson Pump to be invited to provide their expertise during the next phases of the project.