UTEC Constructors, Inc. and Wisconsin Electric Power Company
Commonwealth supported UTEC Constructors, Inc., with engineering and permitting services for 8.5 miles of 138 kV underground transmission line that used a high-pressure, fluid-filled (HPFF), pipe-type cable system insulated with 490 mils of paper insulation in downtown Milwaukee to improve Wisconsin Electric’s capability of delivering power to their customers in that area. Commonwealth provided design engineering, survey coordination, and permitting services for the project.
Seven 138 kV circuits and numerous manhole vaults were installed. Three of the circuits were new, two circuits were replaced, and two circuits were re-routed.
The work included installing pipe-type cable under city streets, highways, railroads, canals, and rivers. Portions of the route also included a 4” HDPE conduit for a fiber optic communication link between substations.
The project involved extensive surveying to carefully align the cable pipe under busy city streets already underlain by an extensive network of sewer, water, gas, steam, signal, and other electrical lines. Long borings were required to cross under two rivers and Interstate Highway 43, and shorter borings crossed under several urban railroad lines. Extensive coordination with the Wisconsin Department of Transportation was needed to cross under four elevated interstate highways that were in the process of being rebuilt. The new lines greatly improve Wisconsin Electric’s capability to deliver power to customers in downtown Milwaukee.