ETI has filed an application with the Public Utility Commission of Texas (“PUCT”) to amend its Certificate of Convenience and Necessity (“CCN”) to add new electric transmission infrastructure in Montgomery and Grimes Counties. ETI is proposing to construct a primarily single-pole double-circuit 230 kilovolts (“kV”) electric transmission line (“proposed transmission line”). This proposed transmission line would connect the proposed Castle Substation along Texas Highway 1774, north of the Texas Highway 249 extension in Grimes County, to the existing Grimes to Ponderosa transmission line at a connection point near the community of Dobbin, Texas. The new Castle Substation will add the needed capacity to serve the growing community in the area and will interconnect with other adjacent substations and distribution feeders, which will improve the electric service reliability in the area.

The application was filed at the PUCT on July 16, 2021 under Docket No. 52304. In its CCN application for this project, ETI presented 75 potential route segments, routing between six alternative cut-in options and two alternative substation sites for the PUCT to use in selecting a transmission line route for this project. ETI has presented 22 different alternative route combinations of the 75 segments ranging from 6.23 miles to 8.23 miles in length, for consideration by the PUCT. The PUCT will choose the substation site, the cut-in point to the existing Grimes to Ponderosa transmission line, and the route of the proposed transmission line. The estimated cost of the proposed transmission line and substation ranges from approximately $48.9 million to $57.4 million depending on the final site and route selected by the PUCT.

The proposed transmission line would be erected utilizing either concrete or steel predominately single-pole structures within a right-of-way that would be up to 125 feet wide. This right-of-way consists of approximately 62.5 feet on either side of the centerline of the proposed transmission facilities, some of which would overlap with other compatible rights-of-way, depending on the final location. Below you will find some helpful links regarding this project:

All routes and route segments included in this notice are available for selection and approval by the Public Utility Commission of Texas.

If you have questions about the transmission line you may contact Brad Coleman, ETI’s Regulatory Transmission Coordinator, at (281) 689-4601 or email the project team at