Our team provided engineer-procure-construct (EPC) services to convert an overhead distribution line crossing to underground. During the project, special design and construction considerations were taken to avoid impacting the Riss Lake Dam, including custom cast-in-place manholes.
As part of the Riss Lake Reliability Project, the initiative included an underground 12-kV circuit crossing the Riss Lake Dam. The cable system is a three-phase cable circuit installed within a six-inch duct, per Evergy standards. The primary cable feeder system connects an existing switchgear enclosure to a new overhead tap along Missouri Highway 9 in the Riss Lake neighborhood.
One of the major challenges was crossing the large neighborhood dam. From the onset, we collaboratively designed to minimize impacts that would affect the dam and residences, and to maintain specifically designated green belt areas. Additionally, care was taken to minimize impacts to an adjacent natural area, an effort that included consulting with the various environmental agencies including the U.S. Fish and Wildlife Service and the Missouri Department of Conservation, and following seasonal tree restrictions for native bat species.
Under the EPC model, we delivered a turnkey implementation with multiple trenchless crossings, real estate acquisition support, permitting, stakeholder management and traffic control.
The underground system was installed via open-cut trenching and horizontal directional drilling (HDD) methods. Special design and construction care was taken for portions of the duct and manhole system across the Riss Lake Dam. Above-grade, primary and secondary feeder sectionalizers and switchgear were installed with their associated foundation bases.