Upgrade to Aging Powerline Infrastructure
Almita Piling Case Studies
PSE&G, Newark, NJ
Situation
Public Service Electric & Gas Company in partnership with a joint venture between Kiewit Power, Henkels & McCoy, and Aldridge Electric needed to replace 17 aging lattice towers for an existing line along the Passaic River near Newark, New Jersey. The towers’ proximity to the river created a number of challenges for the project, such as site access issues due to the changing water levels of the tides, extremely soft soils, and the need for extra corrosion protection from the saltwater. We also faced the additional challenge of building a portion of the line over an old landfill.
Solution
Originally other foundation solutions were recommended for this project, however due to the old landfill site, helical piles presented the best alternative as it resulted in not having to deal with any potential toxic soils from excavation. Working with Kiewit Power Engineers, Almita created a design that addressed the extremely weak soils outlined in the geotechnical report. A load test program was created and executed to confirm the design’s effectiveness. The extension closest to the surface of each pile was galvanized to address the corrosive nature of the surrounding soil.
Results
Almita’s track based installation excavators were able to address the unique access challenges that were created by working near tidal waters. Most of the piles on this project required an embedment depth of 120 feet. Each piles consisted of a 30 foot lead pile and up to 3 30 foot extensions. Upon completion, the project cost approximately $8,000,000 and included 1500 helical piles.