NU 115KV XLPE Underground Transmission Project

In the spring of 2005, construction began on the Northeast Utilities 115 KV XLPE Underground Transmission Project. The project was awarded as a Contractor Quality Controlled (CQC) contract.

MEC provided Northeast Utilities with the final design of the underground installation, as well as substantial value engineering. Adding to the typical challenges of completing an underground transmission project was traffic; construction took place on both quiet country roads and busy city streets.

The 10.5-mile project was divided into three segments - six miles through the Hoyts Hill, in Bethel to Gallows Hill in Redding, CT, a half mile segment with in the property limits of the Bethel Educational Park and the final four mile segment from the Norwalk substation to Norwalk Junction in Wilton, CT. Installation included:

• Over 365,000 feet of conduit
• 57,000 feet of 500 mcm ground cable
• 57,000 feet of temperature sensing fiber optic cable with associated splicing and testing
• 52 thermo couples and test stations
• 166,000 feet of 3000KCMIL  XLPE cable

Additionally, MEC assisted the cable manufacturer, VISCAS, with the completion of 84 splices with in underground vaults and 30 terminations on 85- foot steel towers. Mass. Electric was responsible for the start up and testing of each segment.

As the lead in this joint venture project MEC, along with Kiewit Eastern and Kiewit Industrial, completed this challenging fast track, design/build project in early 2006.