The Public Utility Commission of Texas on March 19 approved, with modifications, Pedernales Electric Cooperative’s (PEC) June 2017 application to amend a certificate of convenience and necessity (CCN) to build, own, and operate a single-circuit, 138-kV transmission line from PEC’s existing Highway 32 substation to its existing Wimberley substation in Hays County.
An agreement – which supports approval of a certain route referred to as, “modified alternative route C” – was executed that resolves all of the issues between the parties to the proceeding, the commission said in its final order.
As noted in the order, the project involves rebuilding and upgrading an existing four-mile, 69-kV radial transmission line connecting the two substations. The project is needed to provide 138-kV transmission service to support the growing loads in Wimberley and provide necessary capacity for backup to feeders at adjacent substations, and eliminate the 138/69-kV autotransformer as a single point of failure risking long-term outages. The commission also noted that the existing Highway 32-to-Wimberley 69-kV line and associated autotransformer are projected to reach thermal capacity by 2024.
The project will begin at the Highway 32 substation, located north of the intersection of Farm-to-Market (FM) Road 32 and FM 12, and extend to the Wimberley substation, located west of FM 2325 in Wimberley, the commission added.
The area traversed by the line is in the Edwards Plateau and the Balconian biotic provinces of Texas. The commission also noted that the southern half of the project crosses rural hill country land used for pasture or rangeland, while the northern half of the project crosses the suburban, residential area south of Wimberley, including crossing the Blanco River.
No parks or recreational areas are crossed by the approximately 3.9-mile, estimated $6.6m agreed route, and there are three parks or recreational areas located within 1,000 feet of the centerline of the agreed route. The commission added that the project is not expected to have a significant impact on parks or recreational areas.
The project is also not expected to have a significant impact on historical or archaeological resources, the commission noted, adding that the agreed route does not cross any known cultural resource sites and that there is one archaeological site located within 1,000 feet of the centerline of the agreed route.
The agreed route crosses potential habitat of federally endangered or federally threatened species, such as the black-capped vireo and golden-cheeked warbler. The commission added that other federally listed species, such as the interior least tern, piping plover, red knot, and whooping crane, are not anticipated to occur, except as rare, non-breeding migrants. Before construction, PEC will conduct a natural resources assessment to consider threatened and endangered wildlife and plant species along the approved route.
The commission also noted that there are 115 habitable structures that are within 300 feet of the centerline of the agreed route, and that considering the highly developed nature of the study area, PEC’s proposed routes minimized, to the extent reasonable, the number of habitable structures in close proximity to the routes.
Among other things, the commission said that PEC is to cooperate with directly affected landowners to implement minor deviations in the approved route to minimize the impact of the project.