Chelsey Nutter, Upper Arkansas Water Conservancy District project manager, discusses the district’s reservoir operations with a group of interested citizens during GARNA-sponsored educational event at O’Haver Reservoir. The equipment is part of the a monitoring station that provides real-time data about reservoir conditions (photo by Joe Stone).
Two local conservation groups organized a water education event featuring a presentation by Chelsey Nutter, Upper Arkansas Water Conservancy District projects manager, and a visit to O’Haver Lake, one of the storage reservoirs managed by the conservancy district.
Sponsored by the Greater Arkansas River Nature Association and Central Colorado Conservancy, Nutter’s presentation provided an overview of water availability, water management and water rights administration in the Upper Arkansas River Valley.
Water storage was a recurring theme of the presentation. As Nutter pointed out:
• Adequate water storage capacity protects against the threat of drought.
• Without additional water storage capacity, water conservation provides limited benefits.
• Water storage aids wildfire suppression.
• Underground water storage provides new opportunities to store water while avoiding evaporation.
Nutter’s report included an update on snowpack in the Arkansas River basin, which stands at 37 percent of median as of May 10, varying from 110 percent at the Fremont Pass snowpack telemetry site to 0 percent at the Glen Cove SNOTEL site.
This wide variation between the northern and southern portions of the basin is not unusual, Nutter said, given this winter’s dominant La Niña weather pattern, which tends to produce warmer, dryer conditions in Southern Colorado and cooler, wetter conditions in Northern Colorado.
And while Chaffee County is currently experiencing moderate drought conditions, reservoirs in the Arkansas River basin are full thanks to above-average precipitation for the two previous years.
Discussing water management challenges, Nutter noted that 80 percent of Colorado’s population lives east of the Continental Divide while 80 percent of the state’s water resources are on the Western Slope. Of approximately 9 million acre-feet of water annually flowing in Colorado’s rivers, the Arkansas River’s share is 164,000 acre-feet.
This limited supply makes storage “incredibly important,” Nutter said. “Storage is the only way to truly plan for drought.”
Reservoir storage in the upper portion of the Arkansas basin is the most beneficial, she said, because less water is lost to evaporation compared to downstream reservoirs. Upper basin storage also supports river flows, benefiting recreation and providing more opportunities to use the water than storage in the lower basin.
The Voluntary Flow Management Program provides a prime example. Through the program, senior water rights owners store water in mountain reservoirs and voluntarily release the water to support recreational activities and aquatic ecosystem health. The water is then recaptured downstream in Pueblo Reservoir, and the owners of that water then use it for municipal, industrial and agricultural purposes.
The Upper Ark district stores water in seven upper basin reservoirs – Turquoise Lake, Twin Lakes Reservoir, Rainbow Lake, Cottonwood Reservoir, North Fork Reservoir, Boss Lake and O’Haver Lake – as well as DeWeese, Conquistador and Pueblo reservoirs.
One of the primary uses of the district’s water is augmentation, which provides an economical way for people and businesses to gain legal access to water without having to go through Water Court.
The district’s blanket augmentation plan gained Water Court approval in 1994 and allows the Upper Ark district, through its Water Activity Enterprise Committee, to replace water from out-of-priority water use across most of Chaffee and western Fremont counties.
Within the district’s augmentation coverage, the district can replace water used out of priority by releasing water stored in a reservoir, thereby preventing injury to owners of senior water rights. (The district is currently working to expand augmentation coverage further into Fremont County.)
Without replacement water provided under the conservancy district’s blanket augmentation plan, many property owners would not be able to legally use water from wells on their land, and obtaining a well permit for new construction would require a private augmentation plan, which could cost upwards of $50,000 for a single household.
Obtaining an augmentation certificate through the district’s blanket augmentation plan costs a one-time fee of $4,215 plus a $165 annual storage and maintenance fee per 0.1 acre-foot augmentation unit (uawcd.com/documents/AugAppCover_Rev_2012-02-22.pdf).
Nutter’s presentation also described innovative projects to enhance the water supply in the Upper Arkansas Valley, including underground water storage.
Building on studies by the U.S. Geological Survey and engineering analysis by Colorado River Engineering, the conservancy district has begun implementing its Trout Creek Park Alluvial Aquifer Storage Project near Johnson Village.
The site provides 10,000-20,000 acre-feet of potential underground water storage in the alluvial aquifer thanks to loose soil consisting of sand, gravel and rock.
Trout Creek Park’s loose soil allows the district to place water into the aquifer through recharge ponds. Once the district’s water reaches the water table, the aquifer’s natural flow gradually feeds that water into the Arkansas River.
One recharge pond has already been constructed, and engineering analysis has determined that it takes almost six years for 50 percent of the water from that pond to reach the river and just over 21 years for all of the water to reach the river.
Additional recharge ponds at key locations will provide more options for timing when the water will reach the river. As the water reaches the river, the conservancy district can then use the water, recapture it in Pueblo Reservoir or exchange the water upstream to place it back into the aquifer or a reservoir.
Aquifer storage avoids the need to permit and construct costly reservoirs. Underground water storage also eliminates most of the evaporative water loss that occurs when storing water in reservoirs.
Following Nutter’s presentation, attendees traveled to O’Haver Lake, where Nutter described district reservoir operations and the district’s stream and reservoir monitoring stations on the lake and on Grays Creek, which supplies water to the lake.
Recent Comments