#Snowpack news (March 18, 2022)

Colorado Snowpack 8-digit HUC view March 17, 2022 via the NRCS. (Click to enlarge)
Colorado Snowpack basin-filled map March 17, 2022 via the NRCS.
Westwide SNOTEL basin-filled map March 17, 2022 via the NRCS.

The latest issue of the newsletter “The Runoff” is hot off the presses from @AspenJournalism #CrystalRiver #RoaringForkRiver #ColoradoRiver #COriver #aridification

A herd of elk graze on Crystal River Ranch outside of Carbondale in spring 2020. The ranch is applying for a new stock watering water right.
CREDIT: Brent Gardner-Smith/Aspen Journalism.

Click the link to read the newsletter on the Aspen Journalism website (Heather Sackett). Here’s an excerpt:

Crystal River Ranch

Crystal River Ranch, the huge expanse of irrigated land just west of Carbondale owned by Sue Anschutz-Rogers, a member of one of Colorado’s wealthiest families, is applying for another water right. This time, the ranch is asking for 5 cfs of water from the Crystal River for stockwatering. The majority of the 5 cfs would be to keep the water in the ditch ice-free so the cattle can drink from it in the winter. CRR pulls water from the Crystal via the Sweet Jessup Canal, and although it’s the first major agricultural diversion out of the lower Crystal, the land it irrigates is several miles downstream. The Sweet Jessup is also one of the biggest diversions on the Crystal and one of the oldest, with a water right dating to 1905. Its three water rights can pull a combined 74 cfs from the river. The Colorado Water Conservation Board and the city of Aurora have both filed statements of opposition to the application. In 2020, Crystal River Ranch filed to maintain a conditional water right for dams and reservoirs on the property, which a water court later granted.

Map of the Roaring Fork River drainage basin in western Colorado, USA. Made using USGS data. By Shannon1 – Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=69290878

Hydrogeologist: Please reject Renewable #Water Resources’ proposal — The #Alamosa Citizen

San Luis Valley irrigation crop circles. Photo credit: The Alamosa Citizen

Click the link to read the article on the Alamosa Citizen website (Chris Lopez):

ERIC Harmon is the type of person Douglas County says it wants to listen to.

He’s a hydrogeologist with expertise on the San Luis Valley aquifers of the Upper Rio Grande Basin. In fact, his team completed the groundwater component of the Rio Grande Decision Support System, which is generally described in state water court documents as “an interactive computer-based system that utilizes data and computer models to help decision makers solve unstructured problems.” The RGDSS is what the state relies on to determine the impact of groundwater pumping.

Harmon is also retired and hasn’t been part of any of the presentations that the three Douglas County commissioners have heard on Renewable Water Resources and its pitch to Douglas County to partner on exporting from the San Luis Valley.

What does Harmon’s experience and expertise say about the RWR proposal? He wrote a letter to the Douglas County commissioners outlining his concerns and recommendation that Douglas County reject the RWR proposal. He has yet to hear back from the commissioners. Alamosa Citizen also asked Douglas County for a response to Harmon’s letter.

Hydrogeologist Eric J. Harmon

“The Renewable Water Resources (RWR) proposal to Douglas County to use ARPA funds should be rejected in favor of less risky projects,” Harmon told the commissioners. “RWR’s project would place undue risks on San Luis Valley (SLV) water users and ratepayers (water customers) in Douglas County. Why? For that, we need to get down into the weeds on the SLV aquifers.”

You can read the letter HERE.

Harmon said he has given expert testimony in the Division 3 Water Court (San Luis Valley) in the AWDI case (1991), the Confined Aquifer New Use Rules case (2006), the Great Sand Dunes In-Place Groundwater Right case (2008) and the Groundwater Rules case (2018).

“Confined aquifer tests in the SLV by my testing team were done as part of Colorado’s Rio Grande Decision Support System (RGDSS) in the early 2000s,” he said to the commissioners. “Our tests showed repeatedly that pumping impacts move outward from a confined aquifer well very rapidly, often causing drawdown (water level decline) up to ½ mile away within one day of pump startup. At several locations, pumping a deep well caused measurable drawdown in layers much shallower than the pumping zone. This is how confined aquifers work: drawdown spreads out very far, very fast. The SLV confined aquifer is ‘leaky.’”

After he sent along his letter to AlamosaCitizen.com for publishing, we asked him a few additional questions. The exchange is below:

AC: What concerns or thoughts, if any, can you share on the drought the San Luis Valley has been experiencing going back to 2002?

EH: Conditions are never static in hydrology. The dynamic nature of water, weather patterns, and the hydrologic cycle means that conditions are always changing. But where there is a long-term drought, the job of scientists and engineers becomes harder. It means that any predictions we are asked to make may be less reliable than we would like, because we don’t always have similar historic conditions we can look back on to compare to.

AC: The streamflow measurements documented by Davis Engineering for the Rio Grande Water Conservation District demonstrate troubling patterns. Have you recently looked at those streamflow measurements? In your view what type of impact is drought, climate change having on the basin and should that be a concern with the RWR proposal?

EH: I have tried to keep up with the general hydrologic trends in the Valley, including snowpack and streamflow. I have also kept up with the trends of Unconfined Aquifer storage change that Davis Engineering has done for RGWCD for many years. It is clear that even after a number of years of self-imposed pumping reductions in the Subdistricts, there is still too little water available to meet the irrigation demand, and to replenish the groundwater storage deficit in the Unconfined Aquifer in the Closed Basin. If drought or climate change persist in the future, as appears likely, then these impacts should be of concern in any new appropriation of water, whether by RWR or anyone else.

AC: Would the change in conditions, drought persistence, declining snow melt, particularly along the Sangre de Cristo range factor into a water court proceeding?

EH: Declining snowpack, earlier and faster runoff, and drought persistence certainly are of concern in the Sangre de Cristos, as they are in the San Juans. Valley-wide, the water supply from the Sangres is considerably less than it is from the San Juans. Smaller drainage areas, the “rain shadow” effect of the San Juans before the snowstorms get to the Sangres, and differences in topography and geology between the two ranges all are factors. If asked, I would advise the water court to look very hard at all of these factors. If groundwater recharge is less in the future than is predicted, it would almost certainly have an impact on the question of injury.

AC: Commissioner Teal said at the last meeting (March 8) that Douglas County has heard repeatedly that there is a “million acre feet” of water in the SLV aquifer. How does one address that notion?

EH: I can’t find any reference to a “million acre feet” in RWR’s proposal or in the presentations to Douglas County. RWR has stated that 22,000 acre-feet per year, the amount they intend to pump, is 2.5% of the aquifer’s annual recharge. So RWR’s number for annual recharge is 880,000 acre-feet. I do not know if this is what Commissioner Teal is referring to. The important thing, however, is not the annual groundwater recharge or the volume of groundwater in storage in the aquifer. The important thing is that the Valley’s water resources are over-appropriated. As Colorado Division of Water Resources officials have pointed out, this means there is no water available for appropriation and full (“1 for 1”) replacement is required under the Rules.

Counting every drop: #Colorado approves $1.9M for high-tech snow, #water measuring program — @WaterEdCO #snowpack

Colorado and othehr Western states are hoping to increase the use of Aerial Snowborne Observatories to better measure the water content in moutain snowpacks. Credit: NASA Hydrological Services

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

Colorado has approved a $1.9 million snow measuring initiative based on NASA technology that will help communities across the state better measure and forecast how much water each winter’s mountain snowpack is likely to generate, using planes equipped with sophisticated measuring devices.

The Colorado Water Conservation Board (CWCB) has been testing the accuracy of the flight-based data measuring work since 2015, according to Erik Skeie, who oversees the program for the CWCB. The board approved funding for the new $1.9 million initiative at its March 16 board meeting.

The new collective, known as Colorado Airborne Snow Measurement group, includes utilities, irrigation districts and environmental groups, including Northern Water, Denver Water and the Dolores Water Conservancy District, among others. In all, 37 water-related groups wrote letters in support of the grant and the measuring program, Skeie said.

Northern Water, which supplies more than 1 million residential, commercial and farm customers on the Northern Front Range, is hopeful the grant will help create an annual monitoring and measurement effort.

”I think it’s a really good program if we can make it sustainable into the future,” said Emily Carbone, water resources specialist at Northern Water.

This map shows the snowpack depth of the Maroon Bells in spring 2019. The map was created with information from NASA’s Airborne Snow Observatory, which will help water managers make more accurate streamflow predictions. Jeffrey Deems/ASO, National Snow and Ice Data Center

Airborne Snow Observatory technology uses planes equipped with LiDAR, a pulsing radar, to develop a grid that contains a deeply detailed picture of the ground when it isn’t covered by snow. Then, during the winter months, those planes fly the same terrain once or more each month when it is covered with snow. In this way, the instruments are able to measure snow depth and snow reflectivity. These data, combined with computer-based models, allow the ASO to generate precise readings on when the snow will actually melt and how much water the snowpack in different regions actually contains.

Traditional forecasts can be off by as much as 40%, and sometimes more. But ASO forecasts have been shown to have accuracy rates of 98%.

As the megadrought in the Colorado River Basin has intensified, and climate change has altered snowfall and traditional patterns of snowmelt, finding better ways to measure the water content of snow has become critical, said Taylor Winchell, a climate adaptation specialist at Denver Water who is overseeing the utility’s flight data program.

A flight from NASA’s Airborne Snow Observatory gathers data about the snowpack above Dillon Reservoir on a flight. Information gathered from the flight helped Denver Water manage reservoir operations. Photo courtesy of Quantum Spatial

Denver Water began using the technology in 2019.

“As the snowpack is changing, the more accurate measurements that we can have help us adapt our operations to a new water future and it helps us make the most of every drop in the system,” Winchell said.

Since the early 1930s, snowpacks have been measured manually and via remote ground-sensing by the federal Natural Resources Conservation Service. Colorado and other Western states use a network of dozens of snotel sites to collect on-the-ground data, but forecasts can change dramatically if the weather becomes volatile, as has been the case more often in recent years.

That volatility and the ongoing drought have made water forecasting even more critical for water agencies. If water supplies come in lower than forecasts indicated, cities and irrigation districts can come up short of water, causing disruptions in deliveries, among other problems.

But ASO technology is expensive. Denver Water spends about $145,000 for two flights, a cost that includes subsequent modeling as well. But the forecasts have proved to be so accurate that the utility is committed to its ongoing use.

California is spending roughly $7 million annually and that cost could grow to more than $20 million if the golden state opts to expand the geographic reach of its ASO program, according to Tom Painter, a former NASA scientist who helped develop the ASO technology and who is now the CEO of Airborne Snow Observatories Inc., the NASA spinoff that is commercializing the technology.

A similar program in Colorado, one expansive enough to cover all the critical mountain watersheds, could cost as much as $15 million annually, Painter said.

The work would include flying some 10 flights per year per river basin during January, February, March and April, with additional flights in late spring as the snow begins to melt. Then flight data would be incorporated into forecast models.

Predicting snowmelt and its water content as warm weather arrives has been a tricky issue for researchers and water utilities because it becomes highly variable.

“That’s when traditional models start to fall apart,” Painter said. “They can’t hold onto the snowpack well enough. So having the data from ASO is nice to keep the forecast accurate. It’s like looking at your checking account balance a couple of times a month.”

Skeie, of the CWCB, said the new approach to measuring what’s known as snow water equivalent, or the amount of water contained in the snow, will take much of the guess work out of annual water forecasts.

And he’s hopeful that the multi-million price tag can be covered by an array of agencies, including the water utilities, the U.S. Bureau of Reclamation and state governments, among others.

“It’s going to take all of that to make it sustainable,” Skeie said. And with the backing of the Colorado Airborne Snow Measurement group, it’s more likely to occur than it has been before.

Using ASO, in combination with snotel data, “is the difference between having someone describe a picture to you, and being able to see it in 4D,” he said. “It’s incredibly useful.”

Jerd Smith is editor of Fresh Water News. She can be reached at 720-398-6474, via email at jerd@wateredco.org or @jerd_smith.

Temperature anomalies by latitude band for each year from 1880 to 2021 — NASA