TPWD issues recommendations concerning Oncor’s proposed Horseshoe Springs to Owl Hills 138-kV project

The Texas Parks and Wildlife Department (TPWD) on Nov. 9 filed with the Public Utility Commission of Texas recommendations concerning Oncor Electric Delivery Company’s proposed Horseshoe Springs to Owl Hills 138-kV Transmission Line Project, including that the commission select a route for the project that would minimize adverse impacts to natural resources, such as “Alternative Route 1.”

As noted in the filing, Oncor proposes to build the new single-circuit line from the proposed Horseshoe Springs switch station to the proposed Owl Hills substation, both located in Culberson County, Texas.

The proposed Horseshoe Springs switch is located about two miles south of the intersection of Farm-to-Market (FM) Road 2185 and FM 652, while the proposed Owl Hills substation is located about 15 miles to the northeast, and west of United States Highway 285 near the Culberson County/Reeves County line.

The proposed line would be about 30 miles long, depending on which route is selected by the commission. The TPWD also noted that Oncor anticipates the use of a self-supporting, double-circuit steel or concrete pole. The typical structure height is anticipated to be 85 feet, but pole height would vary depending upon terrain. The proposed right of way (ROW) width for the project would be about 70 feet.

The TPWD also noted that there are two additional large customer load additions in the area where Targa and Chevron North America Exploration and Production Company (Chevron) have signed agreements for Oncor to provide new electric service in the same vicinity as the proposed transmission line project.

Targa is installing new oil and gas facilities in the area and plans to take electric service from a new Oncor substation called Alligator Draw in Culberson County. The TPWD also said that Chevron is installing new oil and gas processing facilities in the area and plans to build, own, operate, and maintain its own substation located in Culberson County. Oncor is planning to provide service to that facility via a new point of delivery (POD) called Chimney Well.

The certificate of convenience and necessity (CCN) application states that routing the proposed transmission project near the Alligator Draw and Chimeny Well POD locations would provide the ability to connect those new loads to the transmission grid without the need for an additional new 138-kV line. The TPWD added that if the proposed transmission project was not routed near those locations, a new CCN would be needed, tapped from the Horseshoe Springs to Owl Hills 138-kV transmission line. The length of that new tap line would be dependent on the ultimate location of the proposed transmission project.

The TPWD also noted that while Alligator Draw and Chimney Well are not included as part of the proposed transmission project, Oncor’s decision to recommend a route was partially based off of their agreement with Targa and Chevron to provide new electric service in the same vicinity as the proposed transmission project and to route the proposed transmission project near the Alligator Draw and Chimney Well POD locations in order to do that.

The TPWD said that its decision to recommend a route did not take into account the mentioned agreements with Targa and Chevron and only evaluated the proposed routes based on potential impacts to fish and wildlife resources.

Oncor retained Halff Associates to identify and evaluate alternatives and to prepare an environmental assessment (EA) and alternative route analysis report to support its application for a CCN. The TPWD added that Halff evaluated 512 preliminary alternative routes and considered 35 routing criteria addressing such factors as land use. Oncor then selected 34 alternative routes to be filed with the CCN application and chose the approximately 29.9-mile, estimated $34m Route 508 as the route that best meets certain requirements. Route 508, the TPWD added, is about 11.6 miles longer than the shortest alternative route – Route 1 – and estimated to cost about $11.7m more than the least expensive alternative route – Route 1.

The TPWD said that its decision to recommend Route 1 was based primarily on that Route 1:

  • Is the shortest route at 18.3 miles
  • Does not cross any parks and there are no additional parks or recreational areas within 1,000 feet of the ROW centerline
  • Has the shortest length through pasture/rangeland at 12.5 miles
  • Does not cross any upland woodlands
  • Has the shortest length through riparian areas at five miles
  • Crosses 181 feet of potential wetlands
  • Does not cross any open water
  • Contains the fewest number of stream crossings at 11 stream crossings
  • Does not cross any known habitat of endangered or threatened species
  • Does not cross any known rare/unique plant locations within the ROW

“Of the routes evaluated in the EA, Alternative Route 1 appears to best minimize adverse impacts to natural resources while also maintaining a shorter route length,” the TPWD said.

For soil stabilization and/or revegetation of disturbed areas within the proposed project area, TPWD recommends erosion and seed/mulch stabilization materials that avoid entanglement hazards to snakes and other wildlife species.

The TPWD also said that to prevent electrocution of perching birds, it recommends utilizing avian-safe designs that provide appropriate separation between two energized phases or between an energized phase and grounded equipment. Additionally, the TPWD recommends covering energized components with appropriate bird protection materials where adequate spacing cannot be achieved, such as installing insulated jumper wires. TPWD also said that it recommends that lines that cross or are located near rivers, creeks, drainages, wetlands, and lakes have line markers installed at the crossings or closest points to the drainages to reduce potential collisions by birds flying in the vicinity of water features.

Furthermore, the TPWD said that it recommends excluding vegetation clearing activities during the general bird nesting season, March 15 through Sept. 15, to avoid adverse impacts to breeding birds.

In addition, the TPWD said that it recommends having a permitted biologist survey the commission-selected route for any Texas horned lizards that may be in the area that is proposed for disturbance.

The TPWD also said that it recommends taking measures to avoid impacts to aquatic and riparian habitats, which would help minimize impacts to the Pecos pupfish, as well as other aquatic species that may inhabit the project area.

Among other things, the TPWD said that it recommends surveying the commission-selected route for prairie dog towns or burrows and species that depend on them.

About Corina Rivera-Linares 3067 Articles
Corina Rivera-Linares, chief editor for TransmissionHub, has covered the U.S. power industry for the past 15 years. Before joining TransmissionHub, Corina covered renewable energy and environmental issues, as well as transmission, generation, regulation, legislation and ISO/RTO matters at SNL Financial. She has also covered such topics as health, politics, and education for weekly newspapers and national magazines. She can be reached at clinares@endeavorb2b.com.