ELECTRIC TRANSMISSION ROUTING STUDY
LOCATION: WOODBRIDGE, NJ
CLIENT: CONFIDENTIAL
MARKET SECTOR: ENERGY UTILITY
THE OPPORTUNITY
PS&S was tasked with preparing construction level design and associated construction permitting for a high voltage electric transmission line as part of the Woodbridge Energy Center (WEC) project, an electric power generation facility located in Woodbridge Township, Middlesex County, New Jersey. The high voltage electric transmission line connected the new power generation facility in Woodbridge to the existing JCP&L electric sub-station in Sayreville, New Jersey. PS&S’s design included geotechnical investigation and engineering, structural and site civil engineering, surveying and environmental engineering services for approximately 4-mile long high voltage electric transmission line, 2-mile long gray-water line and 0.5 mile long sanitary line. The graywater line and sanitary line were designed and constructed to serve the new power generation facility. PS&S also designed underground electric vaults as part of the electric transmission line.
THE CHALLENGE
The high voltage electric transmission line was proposed to be designed and constructed in three different segments including overhead line supported by approximately 22 monopoles, underground direct buried line and Horizontal Directional Drilled (HDD) line. Due to the challenging subsurface conditions, environmental constraints, and utilities conflicts discovered as a result of PS&S’s investigations along the bank of Raritan River, a modified alignment of the transmission line including special monopole foundation had to be designed for each electric transmission monopole. A part of the graywater line proposed to be installed within an existing utility tunnel below Raritan River posed unique design challenges in navigating the new line through a tight and confined space.
THE PS&S SOLUTION
PS&S developed and designed modifications to electric transmission line alignment and pole locations in such a way that minimized the disturbance to environmentally sensitive areas and eliminated relocation of existing major utilities. A special monopole foundation was designed for each electric transmission monopole that included micro-piles and a pile cap to meet the challenge posed by the poor subsurface conditions. The above unique solutions also resulted in less material handling, expedited construction and were cost effective. A special combination of pipe materials, fittings and anchoring system was designed to address the challenge of accommodating a new graywater line in an existing tunnel.