Oncor seeks approval of proposed 345/138-kV line in Texas

Oncor Electric Delivery Company on July 21 filed with the Public Utility Commission (PUC) of Texas a standard application for a certificate of convenience and necessity for the proposed Riverton-Sand Lake 345/138-kV Transmission Line Project.

As noted in the filing, the new line would connect the proposed Riverton switching station, to be located along County Road (CR) 440 just east of U.S. Highway 285 in Reeves County, Texas, to the proposed Sand Lake switching station to be located about six miles northeast of Pecos, Texas, on the northwest side of Farm-to-Market 3398 in Ward County, Texas.

The proposed line would be built using double-circuit 345-kV transmission structures, with one circuit initially installed and operated at 138 kV, Oncor said, adding that the project includes building the Riverton and Sand Lake switching stations. That work may include station dead-end structures, other structures, bus work, tranformers, grading, fences, and other equipment, the company said.

Noting that the proposed project is to be built at 345-kV standards in order to meet long-term growth for the area, Oncor said that in order to meet future needs, it and American Electric Power (NYSE:AEP) submitted a separate proposal to ERCOT that would bring 345-kV service to the area called the Far West Texas Project.

While the Far West Texas Project is separate from the proposed Riverton-Sand Lake project, ERCOT recommended that the proposed Riverton-Sand Lake project be built using 345-kV construction standards in order to find synergies between the two projects and provide a future upgrade path for the area, Oncor said.

The length of the proposed Riverton-Sand Lake line ranges between about 37 miles to 42 miles, depending on which route is selected by the PUC, Oncor said, adding that its current standard structure for new double-circuit 345-kV construction is the steel lattice tower.

The project area is located in parts of Reeves, Ward, and Loving counties in Texas, with only a portion of the City of Pecos as the only incorporated city extending into the study area, which includes the unincorporated communities of Mentone and Orla.

The routes generally run parallel to the Pecos River in the Southern High Plains, the company said, noting that general land use consists of farming, ranching, and mineral production.

Discussing the need for the proposed project, Oncor said that the project would support continued load growth on the Wink-Culberson and Yucca Drive-Culberson 138-kV transmission lines; improve reliability by connecting the middle portions of two long transmission lines, which would support voltage conditions; provide transmission facilities in an area without transmission facilities; provide transmission voltage feed to new substations, including the new Mentone substation; and improve substation transformer and distribution feeder performance at existing substations.

Oncor noted that it continues to experience load growth in West Texas due to oil and natural gas production, mid-stream processing, and associated economic expansion in the area referred to as the Delaware Basin. Loving, Reeves and Ward counties lie within the West Texas region of the Delaware Basin where deep underground shale deposits referred to as “plays” are providing opportunities for oil and natural gas exploration and production, the company said.  

Improvements in oil and natural gas exploration technologies have increased activity in the area and resulted in electric load growth at substations within the Delaware Basin, Oncor said, noting that that growth has resulted in increased load served on the existing Oncor Wink-Culberson Switch 138-kV Line and the Oncor Yucca Drive Switch-Culberson Switch 138-kV Line, the second phase of which is being built.

The proposed Riverton-Sand Lake line would address reliability concerns by creating a new 138-kV pathway between the Wink-Culberson and Yucca Drive-Culberson lines, Oncor said. The resulting 138-kV system would become more networked and allow bi-directional flow in the area to support voltage conditions, the company said.

ERCOT has recommended the proposed project as the most effective solution to meet reliability needs and provide infrastructure to accommodate future expansion, the company said.

Oncor said that it retained Halff Associates, Inc., to prepare an environmental assessment and alternative route analysis for the proposed project, and that after evaluating the routes, Oncor selected “Route 56” as the route that best addresses certain requirements.

Among other things, Oncor said that no parks or recreational areas owned by a government body or an organized group, club, or church were identified to be located within 1,000 feet of any route centerline of the proposed project. No significant impacts to the use or enjoyment of the parks and recreation facilities located within the study area are anticipated from any route, Oncor said.

Discussing historical and archeological sites, Oncor said that there are no sites within 1,000 feet of the centerline of the alternative routes that have been recorded in the National Register of Historical Places. A total of 13 archaeological sites are located within 1,000 feet of the centerline of the alternative routes, Oncor said.

According to the filing, the estimated total transmission line cost for Route 56 is about $47.5m, and the estimated substation facilities cost is about $8.8m, for an estimated total project cost of about $56.2m.

According to the estimated schedule, right of way (ROW) and land acquisition would begin in August 2018, and be completed in September 2019; engineering and design would begin in June 2018, and be completed in March 2019; material and equipment procurement would begin in November 2018, and be completed in November 2019; and construction of facilities would begin in April 2019, and be completed in December 2019, which is when the facilities would be energized.

About Corina Rivera-Linares 3286 Articles
Corina Rivera-Linares was TransmissionHub’s chief editor until August 2021, as well as part of the team that established TransmissionHub in 2011. Before joining TransmissionHub, Corina covered renewable energy and environmental issues, as well as transmission, generation, regulation, legislation and ISO/RTO matters at SNL Financial from 2005 to 2011. She has also covered such topics as health, politics, and education for weekly newspapers and national magazines.