The Colorado River runs through Glenwood Canyon in this Sept. 23, 2020 file photo.
Despite persistent drought conditions, Glenwood Springs water supply can easily accommodate city users’ needs and more for the foreseeable future, Public Works Director Matt Langhorst said.
While snow water equivalent, aka snowpack, feeding the basins north of Glenwood Springs is 8% below average, Langhorst said the city’s main water sources — Grizzly and No Name creeks — provide more than enough water to meet the city’s needs, even in the dry years.
“If you take how much water comes off both No Name and Grizzly creeks, we could drop down a significant amount and still be good,” Langhorst said.
The first of two primary water sources, Grizzly Creek basin’s lowest snowpack was recorded in 1977, yet the basin still produced more than 4,000 acre feet of water that year. Glenwood Springs uses about 2,200 acre feet of water annually, Langhorst said.
Before pulling from Grizzly Creek, however, the city relies on No Name Creek, but no monitors are in place to monitor snowpack feeding the source.
“Usually in June or July, No Name gets low enough that we turn on the diversion for Grizzly Creek,” Langhorst explained. “We could still live on No Name Creek past July, but we would dry the creek up. We still want water going past the intake for aquatic life and other environmental uses.”
Glenwood Springs Public Works Director Matt Langhorst points out the burn scar directly above the city’s intake structure at No Name Creek in June 2021.
Shannon Marvel / Post Independent
On the high side, the Grizzly Creek basin produced more than 17,600 acre feet of water in 1986.
In addition to water rights on No Name and Grizzly creeks, Glenwood Springs has access to about 500 acre feet of water in the Ruedi Reservoir, southeast of the city, Langhorst said.
Growing demand?
City staff also pay close attention to water availability in relation to future development.
As project proposals flow into city hall, city staff measure the impact on the surplus using an Equivalent Residential Unit (EQR) of about 350 gallons per day for a standard four-bedroom home with two bathrooms.
“When you build, let’s say 300 condo units, they are not a full EQR,” Langhorst said. “(Each unit) is something less, because most will have less than four bedrooms, and it’s doubtful the majority have two bathrooms or 3,500 feet of lawn area.”
The city then applies the relevant EQR per development against its water model to determine whether city infrastructure and water supply can meet the demand.
“We know we can meet demand, but the water model helps us illustrate that,” Langhorst said. “As we look at what (proposed developments) do to our system, and so far it’s neutral.”
Ample water supply, however, doesn’t mean water restrictions are off the table. Langhorst said the city’s watering restrictions in recent years were implemented to facilitate repairs to water plant infrastructure and accommodate for historic spikes of sediment flowing into the system as a result of debris flows.
To alleviate stress on the system and lessen the likelihood of future restrictions, the city invested about $8.5 million in water infrastructure upgrades in anticipation to and as a result of the debris flows.
Following the infrastructure upgrades, the city can treat about 8.5 million gallons a day and store up to 6 million gallons.
On the hottest days, the city typically uses up to 4.5 million gallons a day.
Drier county, higher fire risk
Glenwood Springs’ drinking water supply might not be at risk as a result of the ongoing drought, but Garfield County could still get stuck with cotton mouth.
Brendon Langenhuizen, the Colorado River District director of technical advocacy, said one of the greatest risk factors presented by a county wide drought is increased fire risk.
“Drought slows regrowth on burn scars, which can lead to debris flows like those we experienced in 2021,” Langenhuizen said. “Also the warmer temperatures cause more moisture to evaporate from our soils.”
A massive debris flow, seen here in August 2021, sits in the Colorado River after washing down the Devils Hole drainage in Glenwood Canyon.
Chelsea Self / Post Independent
Drier soils lead to drier vegetation, which increases wildfire risk. Additionally, drier soils absorb more precipitation and snowpack, decreasing the amount of snow melt flowing into the county’s rivers and tributaries, Langenhuizen explained.
The current Natural Resources Conservation Service drought maps show Garfield County’s status as moderate.
“Last year at this time, we were seeing the flows in the Colorado River at about 50% of average,” Langenhuizen said. “This year, we’re seeing those flows at closer to 80% of average.”
River flows can indicate how quickly snow is melting in key watersheds, and river flow averages are gauged over a 30-year timeframe.
“Conditions are looking better this year,” Langenhuizen said.
Regardless of improved river flows, it’s too soon to say whether this year’s drought will be better or worse than years prior.
The monsoon season, which typically spans from June-August, could be the determining factor, he explained.
“We rely on those monsoonal rains,” Langenhuizen said. “And the forecast is calling for hotter, drier weather in the next three months. I’d rather it be the other way around.”
Whereas the county has plenty of drinking water, recreation and agriculture could be impacted by drought conditions, he said.
Early spring drought conditions can create more opportunities for anglers. But, later in the season, waterway temperatures rise due to a lack of snowmelt entering the rivers. Warmer waters stress fish, can cause fish kill and are generally viewed as bad for the fishing environment, said Lindsay DeFrates, a River District media specialist.
Less water in the river overall reduces other river recreation activities, such as stand-up paddleboarding, rafting and kayaking, DeFrates added.
While Garfield County’s water outlook for 2022 is looking up, DeFrates said the area has a long way to go before it clears its drought status.
“Because we’ve been in drought conditions for so long, our storage capacity in our reservoirs is drastically lowered,” she said.
Langenhuizen added, “Ideally, we need three to five really wet, back-to-back years before we could really consider ourselves out of the drought.”
Reporter Ike Fredregill can be reached at 970-384-9154 or by email at [email protected].
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