Southwestern Public Service, Texas regulatory staff and others file stipulation regarding proposed 115-kV line

Southwestern Public Service (SPS), Public Utility Commission (PUC) of Texas staff, and all of the intervenors to the docket (Docket No. 45158), on Jan. 20 submitted to the PUC a unanimous stipulation regarding SPS’ proposed 115-kV NE Hereford to La Plata Transmission Line Project.

The parties said that they submitted the stipulation as representing a just and reasonable disposition of the issues in the docket consistent with the public interest. The parties requested approval of the stipulation and entry of a proposed order, which they attached to their filing.

As noted in their filing, SPS last September filed an application to amend a certificate of convenience and necessity for the proposed line in Deaf Smith County, Texas. SPS requested approval to build and operate a 115-kV line, which the Southwest Power Pool (SPP) identified as needed for reliability to address the overload issues at the existing NE Hereford substation 115/69-kV transformers, Circuit #1 or Circuit #2, which could occur during a single contingency event outage of either transformer.

The project will involve building a new line, which would originate at the NE Hereford substation, located 3.5 miles northeast of Hereford, Texas, in Deaf Smith County, and terminate at the new La Plata substation, a half mile west of the existing Centre Street substation, south of County Road 7, near the western portion of the City of Hereford.

The parties also said that the NE Hereford substation will be reconfigured and a third bay will be added within the existing site. The La Plata substation will be built as a radial feed from NE Hereford, with provisions for expansion, the parties said, adding that SPS would purchase a 70-foot easement – wider in some circumstances – for the transmission line.

According to the proposed order, the La Plata substation is being built to replace the Centre Street substation, which is fed from the NE Hereford substation, but cannot accommodate the proposed 115-kV line due to real estate constraints. The La Plata substation will be built with provisions for expansion to an ultimate arrangement of a three ring 115-kV breaker and a half, with four 115-kV lines and a second distribution transformer.

The parties said that they agree that “Modified Route 6” best meets certain criteria, noting that Modified Route 6 is about 7.51 miles long and the segments that comprise that route are: A, B, F, F*, G*, M, P and Q. Modified Route 6 parallels existing transmission line right of way (ROW), other compatible ROW, and apparent property lines for 7.37 miles, or 98% of its length.

SPS stipulates that the total estimated cost to build Modified Route 6, including substation costs, is about $11.8m. The parties added that SPS estimates that the cost to build the transmission facilities is about $4.9m. The estimated cost to expand and upgrade the NE Hereford substation and build the La Plata substation is about $6.9m, including about $3.8m in associated distribution facility costs. At a total cost of about $11.8m, Modified Route 6 is tied with Route 6 for the second least expensive route, which is $12,678 more than the least expensive route.

“Therefore, the estimated cost of the proposed transmission line constructed on Modified Route 6 and substation facilities is reasonable when compared to the estimated costs of construction on the other proposed alternative routes for this project,” the parties added.

According to the proposed order, the proposed line will have no significant impact on parks and recreational areas, and Modified Route 6 does not cross any recorded cultural resource sites.

Modified Route 6 crosses 1.73 miles of high archaeological or historical site potential, according to the proposed order, which also noted that since the alternative route lengths crossing areas of high archaeological site potential range from 1.53 miles to 2.46 miles, the length crossed by Modified Route 6 is in the lower end of the range.

Construction of the line will not have a significant effect on the geologic or physiographic features of the area, and the line will cause minimal and short-term impact to soil, water and ecological resources, the proposed order said.

In addition, Modified Route 6 will cross no streams; will have about 0.22 mile of ROW across open water, such as ponds and playa lakes; will cross one playa lake; and will have about 0.09 mile of ROW across potential wetlands. SPS will span any wetlands where possible, the proposed order added.

The proposed line will have no significant impact, if any, on aquatic/hydric habitat, and will have no significant impact on local wildlife. The proposed order also noted that no impacts to federal or state-listed threatened or endangered species are anticipated.

Among other things, the proposed order called for SPS’ application to be approved, consistent with the stipulation, and that the approved route for the line is Modified Route 6.

In the event that SPS or its contractors encounter any artifacts or other cultural resources during project construction, work is to cease immediately in the vicinity of the resource and the discovery is to be reported to the Texas Historical Commission.

The proposed order further noted that SPS is to exercise extreme care to avoid affecting non-targeted vegetation or animal life when using chemical herbicides to control vegetation within the ROW, and is to minimize the amount of flora and fauna disturbed during construction of the line, except to the extent necessary to establish appropriate ROW clearance for the line.

Also, SPS is to update the reporting of the project on its monthly construction progress report before the start of construction to reflect final estimated cost and schedule, the proposed order said.

SPS is a subsidiary of Xcel Energy (NYSE:XEL).

About Corina Rivera-Linares 3295 Articles
Corina Rivera-Linares, chief editor for TransmissionHub, has covered the U.S. power industry for the past 16 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