One pipe.
That’s all there is to get water from a 7.2 million-gallon tank at the city of Durango’s water-treatment plant to smaller water tanks and mains that feed every faucet in the city. And the pipe has been in use non-stop since 1954.
There is no other method – no secondary system – for transporting water from the treatment plant near SkyRidge subdivision on College Mesa in east Durango to the mains that feed homes, businesses and government operations.
Repairing and inspecting a pipe without a redundant means of moving water could force city officials to enact water restrictions for all city water customers, said Assistant Utilities Director Jarrod Biggs. A pipe can’t be fixed if there are millions of gallons rushing through it, he said.
“We do have storage tanks (around the city), so it’s not going to be like there’s no water,” he said. “But it’s going to be one of those things where we will be saying, ‘Hey, everybody needs to stop using water and needs to conserve.’”
The risks of water shortages associated with potential disrepair of the decades-old water-treatment plant have caused city officials to explore opportunities to expand treatment capacity to allow for old infrastructure to be turned off and fixed.
The city for years has proposed a new treatment plant that treats water from Lake Nighthorse, thereby providing a second source of water and the desired redundancy. The estimated cost of a second treatment plant: $55 million.
City staff says a new plant would allow the city to update its existing treatment system and provide a backup source if the Florida and Animas rivers became polluted or run low.
But the plan for a new plant is more than 15 years old, and changes to expected water usage and increasing water rates have raised the question: Is a second water plant needed?
The city of Durango water-treatment plant has at least three “choke points” where one pipe carries water from one point to another. The 7.2 million-gallon storage tank, for example, has just one pipe in and one pipe out, said Jason Fast, water facilities supervisor.
One pipe carries water from flocculation basins – where massive paddles stir water to remove sediment and other solids – to a filtration building about 100 yards away.
Two pipes can carry water from the city reservoir, which is filled with water from the Florida and Animas rivers, to a pump that feeds the flocculation basins. But one pipe has limitations – it can’t pump as much water and city crews would have to install infrastructure to make it functional.
The secondary pipe is likely filled with contaminants that would require special treatment to remove, Fast said. Biggs said he has asked operators when the last time the secondary pipes has been turned on and they shrug.
“This stuff hasn’t been used in decades,” Biggs said.
If any of the “choke point” pipes failed, city staff would be “scrambling to get the parts” to fix the problem, Fast said.
“We’d be without water,” he said.
The prevailing solution to the risks posed by aging infrastructure has for years been to build a second water-treatment plant.
A plan for a new water-treatment plant has been in the works since at least 2003, when a water master plan suggested a second plant is the most appropriate solution to the risks posed by possible water plant failures.
The city of Durango bought water rights in Lake Nighthorse in 2012, securing drinking water from the reservoir filled that year, Biggs said. Water rates in 2014 rose in anticipation of a new water plant, a utility cost that’s increased almost every year since.
But the water plan, now more than 15 years old, could use updating. The city expects to obtain a new survey of the city’s water system.
“We’re moving in the direction of (a new treatment plant at) Ridges Basin because it’s been the plan that we’ve been pursuing,” Biggs said. “This is another inflection point where we can say, ‘Is this the right plan?’”
Durango resident John Simpson, who has been critical of municipal spending, said the city needs to take a step back before it commits to building a new water-treatment plant. A new water study must be performed to account for the changes in population, usage and threats to supply that have changed since 2003, he said.
A big change to the previous report is customers aren’t using as much water now as anticipated at the turn of the century, Biggs said. “People have gotten better at conservation,” he said.
Biggs said the water-treatment plant on College Mesa could be retrofitted to bypass choke points and create redundancy, but a wildfire in the Weminuche Wilderness could cause ash runoff in the Florida and Animas rivers – the only two sources of water available to the city for treatment.
The possibility of such a natural disaster is “definitely our biggest risk,” he said.
What’s more, some infrastructure at the College Mesa plant doesn’t meet state standards. Take the earthen dam, for example. Biggs said state inspectors for years have told the city it needs to refurbish the dam, but city crews would have to drain the reservoir to perform the maintenance.
Draining the reservoir would incapacitate water-treatment operations, Biggs said.
“The logistics of rehab cause the problem,” he said.
The life expectancy of many pieces of critical infrastructure at the College Mesa plant is suspect, said Steve Salka, who worked as the city utilities director from 2012 to 2017. He quit over a conflict with former City Manager Ron LeBlanc, he said.
“There’s maintenance on the (College Mesa) plant that we have that has not been done for 65 years,” Salka said. “Some equipment is being held together with bailing wire and Band-Aids.”
There’s not enough room at the College Mesa site to build the infrastructure and capacity needed to take the current water-treatment system off line for repairs, Salka said. The plant is surrounded by residential property, and the city wants to avoid using eminent domain – an often arduous legal process to take private land for public use – if it can, Biggs said.
Building a second plant at Ridges Basin to treat water from Lake Nighthorse would give the city leeway to shut off the College Mesa plant for much-needed repairs, according to Biggs and Salka.
“All the pipes that go into the city start at the (College Mesa) water plant,” Salka said. “There’s no place to build the tanks we need and redundancy at the site now. There’s no land up there. If you have two water plants, you can do maintenance on both: When one plant is down, you can run the other.”
Failure at the existing plant is not a matter of if, but when, he said.
“People say you don’t need it,” Salka said. “They don’t understand how you treat water and how it’s been running for 65 years.”
bhauff@durangoherald.com