Looking good: #Colorado reservoirs reach highest levels in three years — Fresh Water News

Chatfield Reservoir is among those statewide that are reaching highs not seen in three years. Credit: Mitch Tobin, Water Desk, LightHawk aerial photography

Click the link to read the article on the Water Education Colorado website (Jerd Smith):

Thanks to an exceptional year of deep winter snows and frequent summer rains, Colorado’s drought-stricken reservoirs have reached a three-year high, with the statewide average standing at 102% of normal, up from 78% at this time last year.

“Statewide [reservoir levels] increased to above normal for the first time in three years,” said Karl Wetlaufer, a hydrologist and assistant snow survey supervisor for the Natural Resources Conservation Service (NRCS) in Lakewood. “We’ve seen really significant increases in every individual river basin as well as statewide.”

Wetlaufer’s comments came last week at a meeting of the state’s Water Availability Task Force, which monitors rain and snow, weather forecasts, and stream and soil conditions statewide. Wetlaufer is a member of the task force.

The numbers don’t mean all the state’s reservoirs are full, but that their “fullness” at this time is above average for this time of year. Reservoirs are tracked in each of Colorado’s eight major river basins, with the South Platte and Arkansas basins seeing the biggest gains, Wetlaufer said.

Colorado derives the majority of its drinking and farm water supplies from mountain snows that are collected in reservoirs, and as a result, reservoir levels are closely watched.

Colorado reservoirs have reached their highest levels in three years, with the statewide average reaching 102% of normal, according to the Natural Resources Conservation Service.

Hydrologists track water throughout a period of time known as the water year, which begins Oct. 1 and ends Sept. 30.

Water year 2023 has given Colorado and other Western states a major reprieve from a 22-plus-year drought cycle that is considered the worst in more than 1,200 years. Precipitation registered at 108% of normal.

The year “has been wetter than average for a lot of areas around the state,” said Becky Bolinger, assistant state climatologist at Colorado State University’s Climate Center who is also a member of the task force.

This year is giving the whole state a much-needed leg up on moisture going into the winter.

West Drought Monitor map September 26, 2023.

This doesn’t mean that the megadrought is over, though for a two-week period in July, the state was actually drought free, Bolinger said. But since then low levels of drought have returned to the southwest and south-central part of the state, including the San Luis Valley, where Alamosa had its driest summer on record, receiving just 4.32 inches of rain, down from a norm of 7.5 to 8 inches.

Looking ahead, the water picture remains healthy. An El Niño weather pattern that is expected to arrive shortly and continue into the winter and next spring will bring with it wet snows for much of Colorado, with the exception of the northwest mountains.

That same weather pattern means the danger of ultra-dry conditions returning in the next six months is slim, Bolinger said.

“Overall I am not seeing any indicators over the next six months that things are going to turn bad, but in the next year a lot will change. The area I will probably watch is the northern mountains. That is an area that could be at risk for developing drought,” she said.

Still water utilities, coming off a summer when rains kept lawn sprinklers turned down and helped bolster those reservoir levels, are pleased with the situation.

“The South Platte Basin has had a really good summer which translates into lower demand on our system,” said Swithin Dick, water resources administrator for the Centennial Water and Sanitation District in Highlands Ranch. “It’s looking good going into the winter.”

Aspinall unit operations update: Bumping down to 1400 cfs October 2, 2023 #GunnisonRiver #ColoradoRiver #COriver #aridification

Grand opening of the Gunnison Tunnel in Colorado 1909. Photo credit USBR.

From email from Reclamation (Erik Knight):

Releases from the Aspinall Unit will be decreased from 1750 cfs to 1400 cfs on Monday, October 2nd.  Releases are being decreased in response to a reduction in diversions at the Gunnison Tunnel.   

Flows in the lower Gunnison River are currently above the baseflow target of 1050 cfs. River flows are expected to remain above the baseflow target for the foreseeable future. 

Pursuant to the Aspinall Unit Operations Record of Decision (ROD), the baseflow target in the lower Gunnison River, as measured at the Whitewater gage, will be 1050 cfs for October through December. 

Currently, Gunnison Tunnel diversions are 1050 cfs and flows in the Gunnison River through the Black Canyon are around 700 cfs. After this release change Gunnison Tunnel diversions will be 700 cfs and flows in the Gunnison River through the Black Canyon will still be near 700 cfs.  Current flow information is obtained from provisional data that may undergo revision subsequent to review.