Turns out, despite years of devastating drought in Southwest Colorado, it doesn’t take too long for the region’s reservoirs to replenish.
In 1977, Southwest Colorado’s third lowest water year in recorded history, Vallecito Reservoir, which has a capacity of 125,000 acre-feet of water, hit an all-time low, hovering just above 11,000 acre-feet.
“It was looking pretty pitiful,” said Mike Canterbury, reservoir tender for Pine River Irrigation District, the agency that operates Vallecito Reservoir.
But a strong snowpack year after the 1977 drought in the San Juan Mountains nearly filled Vallecito Reservoir back up. In spring 1978, the reservoir northeast of Durango was near capacity at 120,000 acre-feet.
The other year of exceptional drought in recent memory and the lowest water year on record – 2002 – brought water levels in Vallecito Reservoir to just under 15,000 acre-feet. Two years later, the reservoir was almost full again, hitting 120,000 acre-feet.
This year will go down as the second-lowest water year in recorded history. But despite the lack of precipitation, the lowest Vallecito Reservoir got was about 21,700 acre-feet around Oct. 3, Canterbury said.
But already, an uptick in moisture in October has the region’s reservoirs rising. To date, a weather station at the Durango-La Plata County Airport has recorded nearly 2 inches of precipitation this month. (Just 6 inches of rain have been recorded at the weather station for the entire year.)
As a result of the recent moisture, Vallecito is back up to 24,100 acre-feet.
Area reservoirs, at historic lows, rebounding with October rains
And Lemon Reservoir, which has a capacity of about 40,145 acre-feet, is hovering around 6,625 acre-feet. The reservoir, also northeast of Durango, hit a low of about 5,670 acre-feet in the first week of October.
Efforts to reach the Florida Water Conservancy District, as well as the Florida Ditch Co., both of which deal with water out of Lemon Reservoir, were unsuccessful.
McPhee Reservoir gained 2,000 acre-feet in October due to recent rains in the Dolores River Basin, said Mike Preston, general manager for the Dolores Water Conservancy District. The reservoir is currently holding about 169,000 acre-feet, with just 19,000 acre-feet of active storage. The inactive pool is 151,000 acre-feet.
This time last year the carryover into the next water year was 137,000 acre-feet of active storage, thanks to the above average previous winter of 2016-2017. But the historic dry winter of 2017-2018 produced less than 50 percent of average snowpack, and farmers survived off of the previous year’s carryover storage. A full active storage supply for McPhee is 240,000 acre-feet.
Preston said there are two encouraging factors going into this winter. First soil moisture levels for the foothills and mountains are improved compared to last year’s deficit at this time, so when the snowpack releases in Spring, more of it will drain into the reservoir rather than into the soil. Second, the El Niño weather phenomenon is setting up in the Equatorial Pacific, which tends to push storms on a more southerly track with a better chance of hitting Southwest Colorado.
“We used up all of our carryover this year, so we need an average to above average winter to meet allocations,” he said. “A good foundation of soil moisture has been laid down and that sets the stage for building a good snowpack for the reservoir. We already have snowpack above 10,000 feet.”
PRID’s Canterbury, however, said Vallecito is gaining ground.
“As long as we get some snow, we have a good drainage and we should recover pretty quickly,” he said.
In a normal water year, water managers will set releases out of Vallecito Reservoir to about 30 cubic feet per second – the lowest level that can generate hydroelectric power.
But this year, because there was not enough water to go around, Canterbury said releases will be set to about 5 cfs, which will set the dam into a “free spin” – meaning it’s not generating power.
“Once we do that, we ought to start filling even better,” he said. “And of course, we’ll keep doing our rain dance.”
Warren Gabbert, water commissioner for with Colorado Division 7 of Water Resources, said ditches supplied by Vallecito Reservoir ran about 70 to 80 percent of what they would normally run in a good water year.
Area reservoirs, at historic lows, rebounding with October rains
A strong snowpack in 2017 provided some much-needed carryover for this year, he said. But still, water managers had to enact restrictions for water-right users, giving more priority to more senior water-right holders.
This month’s rain has definitely helped, he said.
“We’re a week to 10 days ahead of schedule for snow-water moisture in the high country at this time,” Gabbert said. “Right now, it’s looking good, as long as it continues.”
Aside from storing as much water as possible, and strategically planning water releases, the rest is pretty much up to Mother Nature, Gabbert said.
“Right now, we’re just trying to gain back as much water as we can, as quickly as we can,” he said. “But Mother Nature is the driving force in all of that. You wait and see, then you cross the bridge when you get there in terms of what you need to do.”
Calls to Gabbert’s counterpart for Lemon Reservoir, Tom Fiddler, were not returned Friday.
Lake Nighthorse appears to be one of the fullest reservoirs, if not the fullest, in the state of Colorado. As of Wednesday, the reservoir was at 112,186 acre-feet, which is about 93 percent full.
Calls to Jarrod Biggs, the city of Durango’s utilities director, to find out the city’s reservoir level, were not returned.
PRID’s Canterbury said predictions for a moisture-heavy El Niño weather pattern this winter are a hopeful sign.
“Just seeing the snow up there makes me feel better,” he said.
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