Dixon Water Foundation pushes back on proposed power line route, saying it jeopardizes their mission

Students gathering at the Mimms Ranch for their annual Sul Ross State University range inventory visit. Photo courtesy Dixon Water Foundation.

MARFA — Mimms Ranch, a nonprofit research and demonstration rangeland operated by the Dixon Water Foundation, is joining a number of concerned local citizens in opposing proposed transmission lines that are part of an improvement project initiated by American Electric Power (AEP). 

The mission of the 16,000 acre ranch, located on Marfa’s northwest border, is to promote watershed health through land management. One of the potential power line routes AEP generated would run along their northern property line and cut through six miles of the Mimms Ranch. No lines currently exist in the area, and the construction would create new property easements on 50 feet of either side of the line. New steel poles would measure approximately 75 to 85 feet in height and eight feet in diameter. 

“It would be not only an eyesore on a relatively pristine mixed prairie, which is few and far between these days, but it would also be a big physical scar directly through these research areas that hasn’t existed before,” said Philip Boyd, vice president of science and research at the Dixon Water Foundation. 

AEP is in the process of putting together an application to submit to the Public Utilities Commission (PUC) to replace a 1929-built transmission line that runs through Marfa, beginning at the Alamito Creek substation in the Sal Si Puedes neighborhood, and extends to Fort Davis. After hosting public meetings last month, AEP will now analyze feedback and finalize route options. Construction for the project is expected to begin in 2023. AEP did not respond to requests for comment by press time.

While it is possible the replacement lines could take on a similar route to the existing infrastructure, for its application AEP will submit many route options to the PUC, who will arbitrate the replacement line. Since the 1929 transmission lines were erected, a natural gas pipeline has gone in along the route, a pairing engineers generally try to avoid, said Derek Green of Burns & McDonnell, a construction engineering company working with AEP on the proposal. 

The Dixon Foundation has submitted feedback and letters of support from their partners to AEP opposing the construction of transmission lines on Mimms Unit, a protected high desert grassland which won a Leopold Conservation Award from Texas Parks and Wildlife in 2017. The foundation is conducting a number of ongoing research projects dedicated to range management and the health of grassland bird populations which have declined by 53% in the past several decades.

“Our ranches serve as one of the priority grassland areas in the Chihuahuan Desert and for grassland birds in general in the Central Great Plains here,” said Boyd. 

Alejandro Chávez Treviño and Emily Card, master’s students and researchers with the Borderlands Research Institute, on the Mimms Ranch conducting overwintering grassland bird research. Photo courtesy Dixon Water Foundation.

Power lines would create more perches for predatory raptor birds that use the lines to prey on vulnerable grassland birds, he said. Additionally, between eight and 57 million birds die annually as a result of electrocution and collision with electric utility lines, according to the U.S. Fish & Wildlife Service.

Bird surveys that study species life cycles and habitat preferences are regularly conducted at Mimms. Sul Ross students also utilize the ranch to run range inventory projects, looking at grazing techniques and impacts on vegetation over extended periods of time. 

“Putting a power line through would not only fragment our bird habitat but could also potentially disrupt these decade-long range inventory research projects that have been going on and these monitoring efforts,” said Boyd. 

The imposition of transmission lines would jeopardize the work of the Dixon Water Foundation and their partners, said Boyd, who come to Marfa from all over to learn about grassland ecology. The foundation partners with many entities including Texas Parks and Wildlife, The Borderlands Research Institute, Bird Conservancy of the Rockies as well as organizations in Mexico and Canada.

“We’ve involved a lot of external parties who are gaining a lot of information from [the Mimms Ranch] that they’ve been sharing on a broader scale,” said Boyd. “We look at [the power lines] as disruptive of our long-term work as a foundation.”

Impacts on carefully-managed native vegetation and potential use of herbicides by AEP to maintain access to transmission lines could also pose a threat to the foundation’s ranching operations.

“The idea of having six miles of 100-feet-wide right of ways constructed would undo a lot of this work to protect these native species and native systems, and could have a cascading negative effect in terms of increased water and soil run-off, chemical impacts and spread of invasive species,” said Boyd.

Utilizing the multi-pasture approach to cattle grazing, the foundation regularly rotates its herds around the ranch to promote even graze and pasture recovery. The proposed transmission line route would cross several of the subdivided pastures, creating significant complications for ranch managers, said Boyd.

“Construction of a right of way and subsequent maintenance would require constant coordination with our ranch managers to account for the presence of our herd,” said Boyd. “Developing along this proposed route would also potentially complicate access to water points for our cattle herd and could intersect with the buried water lines that supply those points.”  

The land that makes up the Dixon Water Foundation’s Mimms Unit was originally purchased 14 years ago, but has since expanded. AEP cannot build lines near the Marfa airport, so in the preliminary map power lines are proposed to go around it to the west. Boyd said it seemed as if AEP had outdated county assessment data based on the way they drew up the proposed routes. Part of the route that would affect the Mimms Unit ran along an old property boundary that no longer exists.

“In actuality it is the center of our property because we purchased that ranch and brought it into the Mimms ranch a few years ago,” said Boyd. 

Boyd attended AEP’s virtual town hall earlier this fall, but said there was no mention of grassland birds or pronghorn in regards to the company’s preliminary environmental assessment. He said AEP mentioned they would avoid wetlands, which are few and far between in the Chihuahuan Desert, although Alamito Creek does run through the Mimms Unit.

“I felt like there was some local knowledge that was being overlooked. There’s a lot of nuances to where we live,” said Boyd.

According to AEP’s online project dashboard, they take into consideration various environmental factors when analyzing transmission line routes, including the presence of federally-listed endangered or threatened species and proximity to bodies of water. AEP lists Texas Parks and Wildlife and many other federal and state agencies as routinely being contacted regarding similar projects, but it is unclear whether that applies to this specific project or when that outreach occurs. 

Boyd said the Dixon Water Foundation is prepared to do everything in their power to keep the lines from being built on their property. When AEP submits its application for the project to the PUC, which will likely be soon, landowners, including the foundation, will be notified. At that time they may choose to intervene in the project in order to oppose a specific route.