Joint proposed notice of approval filed in Texas regarding Rio Hondo to Majadas line

The Public Utility Commission of Texas amends AEP Texas Inc.’s certificate of convenience and necessity (CCN) No. 30028 to build and operate the Rio Hondo to Majadas 345-kV transmission line, according to a Jan. 18 joint proposed notice of approval filed by the company.

Commission staff has reviewed and agreed to the joint proposed notice of approval, the company said in a related Jan. 18 motion.

According to the notice, AEP Texas in November 2018 filed an application to amend its CCN to build the line from the existing AEP Texas Rio Hondo switch station to an interconnection point at the proposed Majadas substation that will be owned by Las Majadas Wind Farm, LLC.

The project cost estimate for the line is about $18.8m, the notice said, adding that the project cost estimate for line termination at the AEP Texas Rio Hondo switch station and for line termination at the proposed Majadas substation is about $3.2m.

Discussing the need for the proposed line, the notice said that the project would permanently interconnect the Las Majadas wind project to the ERCOT electrical grid through AEP Texas’ transmission system facilities. The wind generation facility will have an output capacity of 272.8 MW net at the point of interconnection. The notice also said that Las Majadas Wind Farm executed an ERCOT standard generation interconnection agreement with AEP Texas for the interconnection of its wind generation facility.

“Construction of the project will allow the interconnection of the wind farm generation facility to the ERCOT grid through AEP Texas’ transmission system and provide for full output of the wind farm generation of 272.8 MW during normal operating conditions,” the notice said.

AEP Texas proposed one route, which is 9.44 miles long, the notice said, adding that 11 landowners directly affected by the line agreed to the proposed route, all of which have signed consent agreements with AEP Texas regarding the route. The proposed route represents a reasonably direct path from the Rio Hondo switch station, located in Willacy County, to the interconnection point at the proposed Majadas substation, to be located in Cameron County, the notice said.

The proposed route is located in an area that traverses the Tamaulipan Biotic Province, where thorny brush is the predominant vegetation type. The notice added that the study area is predominantly cropland, pastureland, and rangeland, and that it has experienced a moderate degree of alteration due to wind farm development, transportation corridors, and existing transmission lines.

AEP Texas would build the line as a single-circuit line on single-pole steel structures. The notice added that the typical structure for the line would be 110 to 140 feet in height, and would require a 150-foot-wide right of way (ROW).

There are no known habitable structures within 500 feet of the centerline of the route, the notice said. In addition, the proposed route parallels about 61.2% existing transmission line ROW, railroads, public roads or highways, or apparent property boundaries.

The notice also said that there is one park or recreation area within 1,000 feet of the centerline of the proposed route; the line would have no adverse impact on parks and recreational areas.

There are no known historical or archaeological sites crossed by, or within 1,000 feet of, the centerline of the proposed route, the notice said, adding that there is one property listed on the National Register of Historic Places crossed by the centerline of the proposed route. The line would have no significant impact on historical or archaeological areas, the notice said.

Discussing environmental integrity, the notice said, for instance, that the proposed line would cross one stream for 127 feet, cross five irrigation or drainage canals, would parallel irrigation or drainage canals for 1.16 miles, and would cross open water, such as lakes or ponds, for 53 feet. The line would span the stream habitats and AEP Texas would avoid the placement of supporting structures in the streambed.

The notice also said that there are three endangered or threatened plant species of potential occurrence in Willacy or Cameron counties, but expected occurrence of those located in the study area is extremely low. While two sensitive plant communities occur in the study area, neither are crossed by the proposed route. The line is not expected to adversely impact any threatened or endangered plant species or sensitive plant communities, the notice said.

The state-listed threatened black-striped snake, cat-eyed snake, Texas horned lizard, Texas indigo snake, and Texas tortoise are likely to occur in the study area, and if present along the proposed route, could experience minor temporal disturbance during construction activities. Overall, the notice added, the proposed project should not adversely affect those species.

Among other things, the notice said that AEP Texas must conduct surveys, if not already completed, to identify pipelines that could be affected by the line and cooperate with pipeline owners in modeling and analyzing potential hazards because of alternating current interference affecting pipelines being paralleled.

About Corina Rivera-Linares 2807 Articles
Corina Rivera-Linares, chief editor for TransmissionHub, has covered the U.S. power industry for the past 13 years. Before joining TransmissionHub, Corina covered renewable energy and environmental issues, as well as transmission, generation, regulation, legislation and ISO/RTO matters at SNL Financial. She has also covered such topics as health, politics and education for weekly newspapers and national magazines. She can be reached at corinar@pennwell.com.