ALBUQUERQUE — On the edge of Southern New Mexico’s largest city is an earthen dam, built decades ago to keep storm runoff from carving through the desert hills and flooding the populated area below.
New Mexico State University’s golf course is just downstream, and beyond that is a major artery for interstate travel, the university’s sports arena, student housing and a collection of neighborhoods.
The Tortugas Site 1 Dam has never been breached in nearly 60 years, but erosion is taking a toll as deep ruts have developed on the dam’s slopes and unwanted vegetation has sprouted around the spillway.
The dam is just one of 97 dams in New Mexico that are considered high hazard because of the potential for loss of life if they failed and have been determined to be in poor or unsatisfactory condition.
A more than two-year investigation by the Associated Press shows New Mexico leads the nation with the highest percentage — nearly 50 percent — of its high-hazard dams being in bad shape. Nationally, at least 1,680 dams were in that category as of last year.
Some are decades-old and on the list because they lack design and other construction documents that would provide more certainty about their stability. Others have inadequate spillways that would be incapable of withstanding a historic storm.
Many dams on the list in New Mexico also lack emergency action plans, or documents that would detail how authorities would respond to a dam failure and how they would alert downstream residents.
The plan for the Tortugas Dam includes a prescripted emergency broadcast that warns residents not to return to their homes or residence halls to recover their belongings, but rather to head for higher ground.
“Listen carefully. Your life may depend on immediate action,” the suggested message reads.
Alton Looney, the state university’s interim associate vice president for facilities and service, said Dona Ana County emergency management officials conducted an exercise two years ago that addressed a possible flood.
Ultimately, he said, officials determined it would require an amount of water twice the size of the Rio Grande to breach the spillway.
Still, the university is in communication with the irrigation district that manages the dam to ensure it’s prepared if anything were to happen, Looney said.
New Mexico’s poor and unsatisfactory dams are mostly in rural areas around the arid-state — from Dona Ana County north to Lake Maloya, which provides drinking water for the city of Raton.
Spending measures approved by the New Mexico Legislature earlier this year included more than $10 million for dam improvements and other flood control projects around the state. But local government officials say the need always outweighs available funding.
“Aging infrastructure is overall quite a priority for counties — from dams to bridges, rural roads, you name it. Roads are probably our highest, but dams come in right up there at the top,” said Joy Esparsen, deputy executive director at New Mexico Counties.
The association has a seat on the state water trust board, which funds projects such as dam improvements, conservation work and the eradication of invasive species. This year, the board received more than $50 million in requests, even though available funding is closer to $39 million.
The more rural the dam and the fewer people affected, the lower on the list it will be, Esparsen said.
“The need is huge,” she said. “Anything that’s an emergency gets moved up with special criteria in the ranking of projects.”
The Office of the State Engineer has been awarded a special appropriation of $200,000 for a dam safety risk assessment project. The work could begin before the end of the year, said Charles Thompson, head of the agency’s dam safety bureau.
“We’re interested in learning if we’re focusing our efforts on the right things, if we’re fully understanding what our threat is,” he said.
Unlike some other states, New Mexico is spending more on dam safety programs in the 2019 fiscal year than it did in 2011, with a budget of more than $655,000 and six full-time staff positions.
Some lawmakers also plan to ask for more money for dam design and restoration projects during the legislative session that begins in January.