The Texas Parks and Wildlife Department (TPWD), in Feb. 3 comments submitted to the Public Utility Commission (PUC) of Texas, recommended that the PUC select a route that would minimize adverse impacts to natural resources, such as “Route D,” for Sharyland Utilities’ proposed Sale Ranch to Natural Dam 138-kV Transmission Line.
As noted in the comments, the single-circuit line will connect the Sale Ranch substation in Martin County, Texas, to the Natural Dam substation in Howard County, Texas, in order to integrate new load and increase reliability of the electric system. Depending on the route selected, the line will range from 16.78 miles to 19.18 miles in length and will be built on concrete or steel monopoles in a right of way (ROW) about 100 feet wide. The TPWD also said that the typical structure height would be about 95 feet to 110 feet.
Sharyland contracted with POWER Engineers to prepare an environmental assessment (EA) and alternative route analysis. The TPWD also noted that POWER selected “Alternative Route A” as the alternative route that best balances routing criteria related to land use, aesthetics, ecology and cultural resources. Sharyland then undertook further evaluation to consider engineering, design and construction constraints, as well as costs. The TPWD added that Sharyland selected “Alternative Route C” as the route that best addresses certain requirements.
Based on Sharyland’s assessment, Route C:
- Is the shortest of the nine alternative routes, requiring 16.78 miles of ROW
- Is the least expensive route at about $17.4m
- Is a strong selection from a strictly land-use and environmental perspective, being ranked by POWER as the third best route overall
- Has three habitable structures within 300 feet of the ROW centerline, two of which are industrial (as opposed to single-family residences); no route has zero residential structures within 300 feet of its centerline and three of the nine, including Route C, have only one
- Avoids recorded archaeological site 41MT7 – a multi-component site that dates from as early as the Paleoindian period in the Late Prehistoric Period
The TPWD noted that the EA did not provide sufficient information based on surveys (aerial or on-the-ground), remote sensing, modeling, or other available analysis techniques to determine which route would best minimize impacts to important, rare and protected species. Therefore, the routing recommendation is based solely on the natural resource information provided in the certificate of convenience and necessity application and the EA, as well as publicly available information examined in a Geographic Information System (GIS), the TPWD said.
“Of the 11 routes evaluated in the EA, Route D appears to best minimize adverse impacts to natural resources,” the TPWD said. “Route D is the fourth shortest route and does not cross riparian woodlands or brushland. Route D crosses the second least amount of mesquite brushland, mapped wetlands, and streams.”
The TPWD also recommended that if migratory bird species are found nesting on or adjacent to the project area, they must be dealt with in a manner consistent with the Migratory Bird Treaty Act. The TPWD also recommended excluding vegetation clearing activities during the general bird nesting season, March through August, to avoid adverse impacts to that group.
Also, to prevent electrocution of perching birds, the TPWD recommended using avian-safe designs that provide appropriate separation between two energized phases or between an energized phase and grounded equipment. Furthermore, the TPWD recommended covering energized components with appropriate bird protection materials where adequate spacing cannot be achieved, such as installing insulated jumper wires, insulator covers, bushing caps and arrester caps.
According to the EA, of the federal and state-listed species for Howard and Martin counties only the state-listed Texas horned lizard is anticipated to occur within the study area where suitable habitat exists. The TPWD added that it recommends avoiding disturbance of the Texas horned lizard, its burrows, and colonies of its primary food source, the Harvester ant, during clearing and construction.
The TPWD also recommended that Sharyland survey the selected route for prairie dog towns and avoid disturbance of prairie dog burrows during placement of the structures, ROW clearing and line maintenance. If prairie dog burrows would be disturbed as a result of the proposed project, the TPWD recommended that non-harmful exclusion methods be used to encourage the animals to vacate the area prior to disturbance and discourage them from returning to the area during construction.
Among other things, the TPWD recommended that POWER and Sharyland prepare a mitigation plan to provide compensatory mitigation for those habitats where impacts from the transmission line cannot be avoided or minimized. That would include impacts to species and habitats covered under federal law – wetlands and associated habitats, threatened or endangered species – and state resource habitat types not covered by state or federal law, such as riparian areas, the TPWD added.