The Texas Parks and Wildlife Department (TPWD) on June 4 issued recommendations to the Public Utility Commission of Texas regarding AEP Texas, Inc.’s proposed Three Rivers to Borglum to Tuleta 138-kV Transmission Line in Live Oak and Bee counties in Texas.
As noted in the filing, AEP Texas proposes to build the new line, which would be comprised of two segments, with the first segment beginning at the existing AEP Texas Three Rivers substation located northeast of Three Rivers on State Highway (SH) 72 in Live Oak County and extending southeast to the proposed AEP Texas Borglum substation to be located south of the City of Beeville on U.S. Highway (US Hwy) 181 Business in Bee County, Texas.
That segment would be referred to as the Three Rivers to Borglum Segment (TRB), which would be a single-circuit, 138-kV line and could include rebuilding portions of an existing AEP Texas 138-kV line.
The TPWD added that the second segment would begin at the proposed Borglum substation and continue northerly to the existing AEP Texas Tuleta substation in Bee County. That segment, referred to as the Borglum to Tuleta Segment (BT), would be a double-circuit transmission line to accommodate a new 138-kV circuit and an existing 69-kV circuit.
The TPWD also said that depending on the route selected, the total length of both segments of the proposed transmission lines would be about 50 to 80 miles in length.
Noting that AEP Texas retained POWER Engineers, Incorporated to prepare an environmental assessment and alternative route analysis (EA), the TPWD said that the consensus opinion of the POWER evaluators was that primary alternative routes TRB 8 and BT 1 were the routes that best balance land use, aesthetic, ecological, and cultural factors. AEP Texas concluded that alternative routes TRB 19 and BT 1 are the routes that best address certain requirements, the TPWD said, adding that Route TRB 8, for instance:
- Is the shortest route, at 28.32 miles
- Has the longest length using existing transmission line right of way (ROW), at 22.10 miles
The TPWD also noted that Route BT 1, for instance:
- Is the shortest route, at 21.66 miles
- Has the fifth fewest habitable structures within 300 feet of proposed ROW centerline, with 34
The TPWD said that it has selected TRB 19 and BT 1 as the routes having the least potential to impact fish and wildlife resources, noting that Route TRB 19, among other things, has the shortest length of route through woodlands/brushlands, at 9.98 miles, while Route BT 1, for instance, has the second shortest length of route through riparian woodlands, at 0.32 mile.
Route TRB 19 appears to be the route that causes the least adverse impacts to natural resources, the TPWD said, adding that Route BT 1 appears to best minimize adverse impacts to natural resources.
“Of the proposed routes, TRB 19 would appear to be the preferred route,” the TPWD said, adding that it “recommends the [commission] select a route that would minimize adverse impacts to natural resources, such as route BT 1.”
Among other things, the TPWD also recommended that any commission certificate preclude vegetation clearing activities during the general bird nesting season, March 15 through Sept. 15 to avoid adverse impacts to birds. In addition, the TPWD recommended that the company utilize properly installed and maintained erosion control/sedimentation best management practices near aquatic areas during construction to avoid potential impacts to water quality.
In addition, contractors clearing the ROW and installing the line infrastructure should be made aware of the potential to encounter state-listed amphibians in the project area and be instructed to avoid negatively impacting them, if encountered, the TPWD said.
Furthermore, the TPWD said that it recommends that the project area be surveyed for mammal burrows or any structures that may provide suitable habitat for burrowing owls, primarily concrete culverts.
As TransmissionHub reported, AEP Texas filed its application to amend its certificate of convenience and necessity for the transmission line with the commission in April.
As noted in the application, Live Oak County is currently served by two 138-kV lines terminating at the AEP Texas Sigmor 138-kV station, which then serves as a source to the underlying 69-kV system through a nearby AEP Three Rivers 138-kV station. The two 138-kV lines terminating at the Sigmor 138-kV station are the 28-mile, 138-kV San Miguel-Sigmore line and the 66-mile, 138-kV Lon Hill-Orange Grove-Sigmor line.
The current transmission system is not able to reliably serve that area if either of those lines is removed from service in order to perform scheduled maintenance or the result of other outage conditions, the application added.
AEP Service Corporation (AEPSC), on behalf of AEP Texas, submitted a proposal to the ERCOT Regional Planning Group (RPG) to address the reliability of the Live Oak County area electric system. After being reviewed by the ERCOT RPG and the ERCOT Technical Advisory Committee, the proposed project was recommended by the ERCOT Board of Directors as needed to support the reliability of the ERCOT regional transmission system.
According to the estimated schedule, construction of the facilities would begin in June 2021 and be completed in August 2022, which is also when the facilities would be energized.