Siting and Routing for 345 kV Transmission Line

With a forecasted increase in industrial load and corresponding outage concerns along the Gulf coast in Texas, our client needed to construct a new 345 kV transmission line.

Our team was brought in to prepare an Environmental Assessment and Alternative Route Analysis to support  the utility’s application for a Certificate of Convenience and Necessity (CCN) to the Public Utility Commission (PUC) of Texas.

Our technical experts collected data to identify constraint and opportunity areas for routing the proposed transmission line, developed a network of geographically diverse alternative routes, and conducted an environmental impact analysis.

Based on the outcome of the analysis, our team recommended two routes  we believed best addressed the requirements of the Public Utility Regulatory Act (PURA) and the PUC Substantive Rules. The project received approval from the PUC of Texas.

Challenges & Accomplishments

• USACE-Designated Columbia Bottomlands: The U.S. Army Corps of Engineers (USACE)-designated Columbia Bottomlands comprise approximately 250 square miles of unique riparian habitat in southeast Texas that boast hundred-year-old oak trees and the last of the Brazoria palm tree. The habitat is a key stop-over for a migratory bird population of 239 million individual birds representing 237 species. Because the project passed through this sensitive ecological area, our client faced the possibility of needing to obtain an Individual Permit that would have significantly delayed the permitting and construction schedule of the project. Through careful planning, we helped Energy them identify routes that avoided these areas as well as known waters of the U.S., including wetlands, which reduced anticipated impacts and avoided the need for an Individual Permit.
• State and Federally-Owned Lands: The study area included the U.S. Fish and Wildlife Service (USFWS)-managed San Bernard National Wildlife Refuge and two large state-owned properties: one managed by the Texas Parks and Wildlife Department (TPWD) and one managed by the Texas Department of Criminal Justice (TDCJ). We helped our client develop a route that completely avoided the national wildlife refuge. Additionally, the routing and siting team coordinated with TPWD and TDCJ to minimize impacts to those properties while still providing the geographically diverse routing options the PUC requires.

Project Features

• Between 54 and 85 miles of new 345 kV transmission line
• USACE-designated Columbia Bottomlands
• Section 10 water crossings
• San Bernard National Wildlife Refuge
• TPWD Justin Hurst Wildlife Management Area
• TDCJ – Clemens Unit
• Coastal Management Zone
• Expansion of State Highway 36
• Existing residential and industrial development

POWER’s Services

• Agency consultation
• Alternative route analysis
• Bald eagle nest helicopter surveys
• Clean Water Act permitting
• Constraints and opportunities analysis
• Engineering cost support
• Expert testimony
• Historical and archaeological surveys
• Open houses
• Public involvement
• Resource inventories and land use review
• Study area development
• Wetland delineation