The Public Utility Commission of Texas amends Electric Transmission Texas’ (ETT) certificates of convenience and necessity (CCNs) to include the construction and operation of the proposed Stewart Road 345-kV Transmission Line in Hidalgo County, along “settlement route B3,” according to a proposed order sent to the commission on Jan. 16 by the Office of Policy & Docket Management.
The commission will consider the docket (PUC Docket No. 47973) at an open meeting scheduled to begin on Feb. 7 at the commission’s offices in Austin, Texas, the office said, noting that parties in the proceeding are to file corrections or exceptions to the proposed order by Jan. 30.
As noted in the proposed order, ETT in February 2018 filed with the commission an application to amend its CCNs for authority to build, own, and operate the proposed line.
The proposed double-circuit, 345-kV line would connect AEP Texas Inc.’s Stewart Road substation, as expanded, to an interconnection point along ETT’s portion of the existing North Edinburg-to-Palmito 345-kV transmission line. AEP Texas and Sharyland Utilities each own about half of the North Edinburg-to-Palmito 345-kV line, with AEP Texas owning and operating the North Edinburg substation and the western half of the line, and Sharyland Utilities owning and operating the Palmito substation and the eastern half of the line.
AEP Texas agreed to the interconnection of the proposed line to the AEP Texas Stewart Road substation, the proposed order added.
The proposed line is needed to support the reliability of the regional transmission system.
The proposed order also said that the right of way (ROW) width would typically be 150 feet. Construction of the proposed line would consist of double-circuit steel monopoles using 954.0 aluminum-conductor steel-reinforced Cardinal conductors.
In the application, ETT identified route B3 as the route that best addresses certain routing requirements. The proposed order added that ETT in November 2018 filed a unanimous settlement agreement in which the parties to the proceeding agreed to an amendment of ETT’s CCNs for the proposed line using filed route B3 – the settlement route, which is 4.9 miles long and has an estimated cost of about $16.8m.
The proposed order noted that the estimated cost of the expansion of the existing AEP Texas Stewart Road substation that is required to connect the proposed line is about $27.9m.
The total estimated cost for the proposed line using settlement route B3, plus the substation’s estimated costs, is about $44.8m, which the proposed order said “is reasonable when compared to similar proposed transmission lines.”
The settlement route parallels existing transmission line ROWs or other compatible ROWs or apparent property lines for 4.18 miles of the 4.90-mile route, which is 85.3% of the route.
The proposed order added that the proposed line would not significantly impact the use or enjoyment of parks or recreational areas.
Also, while the settlement route does not cross any recorded archaeological sites and does not come within 1,000 feet of any known archaeological sites, the settlement route crosses 4.10 miles of areas of high potential for archaeological sites. The proposed order added that the settlement route, and all application routes, cross the Louisiana-Rio Grande Canal Company Irrigation System, which is listed in the national register of historic places.
Potential impacts to the Louisiana-Rio Grande Canal Company Irrigation System have been mitigated through the careful selection of routing alternatives, and additional mitigation can be provided by pole placement, spanning resources, and construction measures during the construction process as necessary, the proposed order said.
Discussing environmental integrity, the proposed order noted, in part, that ETT does not anticipate significant impacts to wetland resources, ecological resources, endangered and threatened species, or land use as a result of construction of the proposed line.
Among other things, the proposed order said that ETT must conduct surveys, if not already completed, to identify pipelines that could be affected by the transmission line and cooperate with pipeline owners in modeling and analyzing potential hazards because of alternating current interference affecting pipelines being paralleled.
Also, if ETT encounters any archaeological artifacts or other cultural resources during project construction, work must cease immediately in the vicinity of the artifact or resource and the discovery must be reported to the Texas Historical Commission.
The proposed order also said that before beginning construction, ETT must undertake appropriate measures to identify whether a potential habitat for endangered or threatened species exists and must respond as required.