Red Mesa Reservoir must make improvements or face demolition

Thursday, Aug. 16, 2018 7:26 PM
Trent Taylor, a board member of the Red Mesa Reservoir and Ditch Co., walks on the outlet tower near the reservoir’s dam Wednesday. Taylor is exploring ways to enlarge the reservoir, often called Mormon Reservoir, located on the Dryside of La Plata County, southwest of Durango.
The spillway at Red Mesa Reservoir has been expanded to handle a 100-year flood. The Red Mesa Reservoir and Ditch Co. has until 2028 to make improvements to handle a 1,000-year flood. The project could cost as much as $9 million.
Red Mesa Reservoir, also known as Mormon Reservoir, is located on the Dryside of La Plata County, southwest of Durango. The reservoir must be improved to handle a 1,000-year flood or it will be razed.
Released water from Red Mesa Reservoir could flow down a series of irrigation ditches to Long Hollow Dam.
The outlet control at Red Mesa Reservoir was installed in 1945 and is simpler to use than the automated control at Long Hollow Dam, says Trent Taylor, a board member for the Red Mesa Reservoir and Ditch Co.


The clock is ticking for managers at Red Mesa Reservoir who have six years to raise millions of dollars for state-ordered repairs to prevent the dam’s demolition.

“It’s going to be a challenge,” said Trent Taylor, an operator of the dam and a board member of the Red Mesa Reservoir and Ditch Co. “But we have to do something, and we will.”

Red Mesa Reservoir, historically known as “Mormon Reservoir,” is about 30 miles southeast of Mancos, off Colorado Highway 140 before the unincorporated community of Kline.

The relatively small reservoir, which has a capacity of about 1,175 acre-feet, provides water to about 50 people in the notoriously water-strapped western part of La Plata County, commonly referred to as the “Dryside.”

The dam was originally built in the early 1900s, Taylor said, by members of the Church of Jesus Christ of Latter-day Saints who used a “Fresno scraper,” a machine pulled by horses for building canals and ditches.

But a major flood washed out the earthen dam in 1911. It was rebuilt over the next two decades and completed in 1945. Aside from minor improvements here and there, Red Mesa Reservoir has remained largely unchanged, Taylor said.

In the 1980s, however, Colorado’s Division of Water Resources deemed the dam’s spillway (the structure used to deal with overflows) inadequate to handle waters expected in a 100-year and 1,000-year flood.

Calls to the Division of Water Resources were not returned.

Plans over the years to enlarge the dam and improve the spillway never came to fruition, Taylor said. And the issue, for the most part, seemed to lay dormant, especially because the parched region has never had to use the existing spillway.

But this January, the spillway was condemned during a Division of Water Resources inspection, with the agency placing water restrictions on the reservoir until fixes were made.

To save this year’s water season, which has been one of the driest in recorded history, reservoir managers and the water division struck a deal: improve the spillway for the 100-year flood and restrictions would be temporarily lifted.

“We didn’t dare drain the reservoir this spring,” Taylor said.

It cost about $25,000, but reservoir managers were able to expand the spillway to meet the requirements of the 100-year flood within a month or so. But that’s only a short-term fix to a much larger problem.

“It’s going to be a heavy lift for that community on the west side of the county,” said Bob Wolff, a board member on the Southwestern Water Conservation District. “But they (the water division) don’t want water going over a dam because it erodes in a heartbeat and can put downstream people at risk.”

To expand the spillway to handle the waters of a 1,000-year flood, Taylor estimated it would cost up to $9 million. If improvements aren’t made, the state will raze the dam, he said, at the cost of about $1.5 million.

There are more than 90,000 dams across the country, according to the U.S. Army Corps of Engineers. But as America’s dams age, funding for maintenance has become scarce, a far cry from the dam-building heyday of the 1920s.

The Association of State Dam Safety Officials in 2016 said it would cost $60 billion to make necessary repairs to dams across the country.

Taylor believes the Division of Water Resources put pressure on Red Mesa Reservoir in response to the near crisis at California’s Oroville Dam. In February 2017, Oroville’s spillway almost failed.

The situation isn’t anywhere as dire, but the state has an obligation to ensure public safety, Taylor said.

As for funding options, the answer may come with reservoir managers getting creative.

Opportunities for grants are available, especially through the Colorado Water Conservation Board. But the board prefers to award grants when a project has a broader reach.

“We really look for projects that serve multiple purposes and have multiple benefits,” said Lauren Ris, deputy director of the CWCB. “And if folks can come together in a collaborative way, that helps. It’s definitely something we as a staff look for when evaluating grants, and we encourage it.”

The reservoir’s greatest hope in surviving the ordeal, Taylor said, is teaming up with managers at the recently built Long Hollow Dam, which is near Red Mesa Reservoir and has a capacity of nearly 5,400 acre-feet.

The details haven’t been worked out yet, but the two dams have an opportunity to work together, which in turn, could help hundreds of people on the west side of the county have better access to water.

Attempts to reach Brice Lee, president of the La Plata Water Conservancy District, were not successful Friday.

As an added bonus, the water in Red Mesa Reservoir predates the 1922 Colorado River Compact, the most valuable water rights in the state, Wolff said. Essentially, they are not subject to requirements in the seven-state deal.

Taylor said it’s likely Red Mesa Reservoir would also enlarge its capacity to intake the district’s full water rights of 4,070 acre-feet.

The district has until 2021 to draft a plan, Taylor said, and must start construction by 2024. The project must be completed by 2028, which he jestingly calls “D-Day.”

“People don’t realize how much of a benefit it is to turn on your tap and have potable water,” he said.