Jun 11, 2021
Updated Tuesday, August 24, 2021
ACUA is embarking on a major infrastructure improvement to a critical force main that conveys wastewater from Ventnor, Longport, Margate, and a section of Egg Harbor Township, to our wastewater treatment plant in Atlantic City. The $3.7 million dollar investment will upgrade the current pipeline, which prematurely deteriorated from the infiltration of grit (sand and small rocks) from the shore communities.
The pipeline being replaced stretches under the Atlantic City Expressway and NJ Transit line and across the bay to Bader Field in Atlantic City. The contractor used a new and unique method to complete the underwater replacement. A directional bore worked its way across the area, digging a hole large enough for the new pipeline. Once it reached Bader Field, the contractor "pulled" the new pipeline through the opening.
The newer technology minimizes disturbance, not only for marine activity, but also of the substrate, water, plants and marine life in the bay. The old way would close the waterways to marine traffic as pipes would need to be floated out to the location and dropped into the dug-out area underwater.
Construction of the original pipeline in the 1970s
The directional bore began drilling on Thursday, June 10, 2021. This part only took a few days.
Now that the new pipeline is in place, it needs to be connected to the current system on both sides. Currently, the contractor is connecting the pipe on the Bader Field side. The area around it had to be excavated down 30 feet to the level of the pipe. To do this, a temporary cofferdam was built. This structure is made of steel sheeting on the outside, with steel I-beams for bracing. Construction of the cofferdam took about two weeks. Water is pulled out through pipes in a well point system. The tubing pulls water out of the excavation area as work is being completed. Other tubes pump fresh air into the hole to dilute the higher concentrations of sulfur present at that depth in the marsh environment.
Once the pipe connection has been completed, the hole will be backfilled and the cofferdam will be removed. The same process will be completed on the other end, closer to our wastewater treatment facility. The excavation on this end will not be as deep.
The new pipeline is made with HDPE rather than steel, which is expected to withstand any grit in the system.
Stay tuned for more progress on this important improvement project!