Part of the streamflow management infrastructure at the city's existing hydropower plant on Maroon Creek. Groups in the community are calling for stream gauges to be installed below the city's infrastructure on both Maroon and Castle creeks.
Part of the streamflow management infrastructure at the city\ Credit: Brent Gardner-Smith

Two groups critical of the city of Aspen’s proposed hydropower plant along the banks of Castle Creek are now raising funds to install stream gauges on that stream, as well as Maroon Creek.

A stream gauge suitable for inclusion in the U.S. Geological Survey (USGS) system cost between $20,000 and $35,000 to install, depending on the site, and $16,000 a year to operate.

Saving Our Streams, a recently formed nonprofit that is challenging the city’s proposed hydro plant, wants at least one gauge on both Castle and Maroon creeks in order to keep an eye on how much water is left in the streams below the city’s diversion dams.

Maureen Hirsch of Saving of Streams has contacted federal officials with the USGS, who have agreed to make a site visit this winter to the Aspen area.

“If somebody is interested in a new stream gauge, we are certainly open to talking to them,” said David Brown, the director of western Colorado operations for USGS, who is based in Grand Junction.

Friends of Rivers and Renewables (FORR), a new initiative from the Aspen-based Public Counsel of the Rockies, also wants gauges on those two streams.

The group is also calling for new gauges on the Roaring Fork River in Aspen, on Hunter Creek and on the lower Crystal River.

“It’s time to get the Roaring Fork River basin properly gauged,” said Tim McFlynn of Public Counsel for the Rockies. “It’s shockingly overdue.”

But the expense of doing so can be shocking as well.

To install five streamflow gauges up to the standards of the USGS and to cover 10 years of operations and maintenance on them could cost $900,000.

There were operating gauges in place high on both Castle and Maroon creeks from 1969 to 1994, but they were taken off-line due to the cost of operating them and the perceived value of the data they were producing.

However, when consultants for the city modeled how much water would be available to both the proposed hydro plant and the streams, they used the 25 years’ worth of data gathered from the now defunct stream gauges, along with data kept by the city at its diversion points.

City water officials are able to track — at their diversion dams lower on Castle and Maroon creeks — how much water they divert from the streams and how much water they leave in the streams.

But the city does not have gauges installed such as those used by USGS or the state’s Division of Water Resources.

Gauges are especially useful when trying to protect an instream flow regime, such as those set by the state to protect a river’s natural environment “to a reasonable degree.”

Lee Rozaklis, a consultant with AMEC Earth and Environmental Inc., was hired by Pitkin County’s Healthy Rivers and Streams board to review the city’s water use for the proposed hydro plant.

He concluded that “as part of the project, Aspen should provide real-time measurement and publicly accessible reporting of daily flow bypasses at the Castle Creek and Maroon Creek diversion structures and flows below the Castle Creek and Maroon Creek hydropower discharge points.”

Phil Overeynder, a utilities engineer with the city who once led the utility department, does not dispute the value of stream gauges.

“It would be a good thing,” Overeynder said. “It would be useful information for the city and for other water users.”

Indeed, a 2011 agreement between the city and the Colorado Division of Wildlife to monitor Castle and Maroon creeks calls for gauges to be installed on both creeks, although it’s not clear in the agreement what type of gauge is required.

Bill Blakeslee, the state water commissioner charged with managing local water diversions, said gauges are the best way to solve water disputes.

“Anybody can produce a study, but without a consistent measuring device in the stream, everybody is just kind of blowing smoke,” he said.

But Blakeslee warned that enthusiasm for new gauges tends to wane when it comes to paying for the ongoing maintenance and operational costs of them, which are prone to freezing up in the winter and need to be routinely checked.

Leaders from both Saving Our Streams and Friends of Rivers and Renewables say they are seeking funding for gauges from both private and public sources.

Saving Our Streams’ members include two billionaires and several other wealthy homeowners on Castle and Maroon creeks. Hirsch said one member already has agreed to fund one gauge.

Yasmine DePagter, another SOS member, said the group plans to conduct a broader grassroots funding effort.

“This should be a community effort,” DePagter said.

Chelsea Congdon, who chairs the water committee for the Snowmass-Capitol Creek Caucus, has signed on to lead the efforts of the new group, Friends of Rivers and Renewables.

Congdon, who also worked on Western water issues for 12 years with the Environmental Defense Fund, wants to convene interested parties and discuss new developments in gauging technology, which could possibly cut the installation costs in half.

But she agrees that new gauges probably need to be up to the standards of either the USGS or the state’s Division of Water Resources, which also maintains a system of gauges.

“One of the things we need to make sure of is that if we help facilitate a gauging system, that it is a system that people buy into,” Congdon said.

Other groups also see the need for more gauges.

In its draft 2011 “State of the Watershed” report, the Roaring Fork Conservancy called for new or additional gauges on Hunter Creek, Castle Creek, Maroon Creek, Snowmass Creek, the Crystal River and on the Roaring Fork River.

Pitkin County Attorney John Ely, who is the key adviser to the healthy streams and rivers board, said more gauges have been on its agenda since its inception in 2009. The board, which is funded by property taxes, now has a grant program to help fund river-health initiatives.

Ely has recommended mapping out the need for gauges throughout the Roaring Fork River basin.

On Thursday, the river board will hear a presentation from Rozaklis and another streamflow expert, Greg Espergren, on a proposed methodology to better protect the environmental health of local rivers.

Gathering accurate flow data is one of the keys to their proposal.

Brown, of the USGS, said gauges are typically a cooperative effort in the state.

“Here in Colorado, there are over 100 entities that provide funding to the streamflow gauging program,” he said.

Brown said taxing entities, such as a city, can apply for federal matching funds for gauges and private entities also can contract directly with USGS to finance a gauge.

Editor’s note: This story was also published in the Aspen Daily News on Feb. 13, 2012.

Brent Gardner-Smith, the founder of Aspen Journalism, and who served as AJ’s executive director until August 2021 and as editor from 2011-2020, is the news director at Aspen Public Radio. He's also been...