Grand Lake advocates to ask lawmakers to endorse restoration, as clarity issues persist

Advocates for Grand Lake, Colorado’s largest and deepest natural lake once known for its crystal clear waters, will ask state lawmakers in 2024 to approve a resolution calling for its restoration in an effort to win statewide support and break a bureaucratic stalemate that has stymied efforts to restore its clarity.

The move comes one year after the legislature’s Water Resources and Agriculture Review Committee was asked to intervene in the issue, which centers on the federal Colorado-Big Thompson Project (C-BT). The C-BT moves water through Grand Lake before pumping it under the Continental Divide to the Front Range, where it serves 1 million people and hundreds of farmers. Lawmakers declined to act at that time, citing the need for more study.

Advocates have long been frustrated at the failure to find a permanent fix to the lake’s clarity issues, whether it’s through a major redesign of the giant system or more operational changes. They are hopeful that if they can get state lawmakers to approve the resolution, they may have more leverage with their federal partners.

“[The resolution] doesn’t have any teeth,” said Mike Cassio, president of the Three Lakes Watershed Association, a nonprofit focused on protecting Grand Lake and two reservoirs in the area: Granby Reservoir and Shadow Mountain Reservoir. “But it is something state legislators could vote on, and it would put people on the record.”

For years, the once-clear lake has been clouded by turbidity created by the pumping. Before the C-BT was built, clarity was 9.2 meters, roughly 30 feet. The goal now is 3.8 meters, according to Esther Vincent, Northern Water’s director of environmental services. Northern Water jointly operates and maintains the C-BT along with the U.S. Bureau of Reclamation.

Historic protections?

Early on locals had hoped the lake would be protected from damage caused by the giant water system. A 1937 federal law, U.S. Senate Document 80, was approved in part to protect Grand Lake’s recreational and scenic values, and a 15-year-old state standard was designed to improve water clarity, but officials acknowledge more must be done.

As advocates seek to broaden support, the Three Lakes Technical Committee, a working group that includes multiple federal and state agencies and interest groups, restarted formal meetings Sept. 1 for the first time since 2014, though other groups have met more often, examining annual operating results and testing new management scenarios. The idea behind restarting the technical meetings, is in part, to identify shorter-term fixes that could be quickly implemented and paid for more easily.

Vincent sees the resumption of the technical committee meetings as a hopeful sign.

“We have a lot of people who are newer to the work and it’s important that we bring everybody up to speed,” she said. “We would like to see clarity get better.”

This year, thanks to an exceptionally wet winter and spring, and high runoff, the lake has been clearer than locals have seen it in decades.

Grand Lake Mayor Steve Kudron said seeing the lake temporarily improve this summer has been gratifying.

“My goal has always been to maintain the recreational, scenic natural quality of Grand Lake and I have that this summer … I should smile while keeping an eye on what we’re going to do when it gets worse,” Kudron said.

A Colorado landmark

The lake is considered a prime jewel in Colorado’s scenic landscapes. Located on the western edge of Rocky Mountain National Park, it has been a tourist haven since the late 1800s.

But it changed when the C-BT began construction in the late 1930s. The system gathers water from streams and rivers in Rocky Mountain National Park and Grand County, and stores it in man-made Lake Granby and Shadow Mountain Reservoir. From there it is eventually pumped up into Grand Lake and delivered via the Adams Tunnel under the Continental Divide to Carter Lake and Horsetooth Reservoir on the Front Range.

During the pumping process, algae and sediment from Shadow Mountain are carried into Grand Lake, clouding its formerly clear waters and causing algae blooms and weed growth, and harming recreation.

In 2008, the Colorado Water Quality Control Commission moved to set a clarity standard, but it has since been replaced with a clarity goal and the aim of achieving “the highest level of clarity attainable.”

Northern Water and others have implemented different management techniques, including changing pumping patterns, to find ways to improve water quality in all three water bodies. In some years, Northern has been able to improve clarity, but not to historical levels.

In 2016, Reclamation took the first steps required under the National Environmental Policy Act of 1969 (NEPA) to do the scientific and engineering studies and public hearings that would be required for a major structural fix to the system. But Reclamation stopped the process in 2020, saying that it could not definitively establish any structural alternatives that would work, nor could it find a way forward on funding what could be a wildly expensive project, according to Jeff Rieker, manager of Reclamation’s Eastern Colorado Area office.

Redesigning the massive 85-year-old water project could easily cost hundreds of millions of dollars, officials said and would take years of permitting. It would also likely require local partners to share some of the cost.

Long-running frustrations

Rieker said the resumption of the technical meetings, scheduled to occur monthly through next April, could help move everyone closer to a solution.

“We certainly recognize the concerns and frustrations that are out there … my hope is that through these dialogues that we are having this year, it will lead to people being less frustrated,” Rieker said.

Cassio said one avenue that may hold promise would be to focus on Shadow Mountain, a shallow manmade reservoir whose warm temperatures, high levels of algae and weeds, and sediment loads do the most damage to Grand Lake. If technology could be introduced to harvest the weeds and aerate Shadow Mountain, that could improve Grand Lake without a major federal infrastructure project.

Rieker said that his agency is very interested in that approach.

At the same time, Northern and Reclamation, along with other Grand Lake interest groups, will update the Colorado Water Quality Control Commission in November on their efforts since 2016. Whether the state will take additional action isn’t clear yet.

Cassio said he remains deeply worried that the lake’s long-term condition will not improve, especially as more frequent droughts and climate change reduce streamflows and degrade water quality even further.

Getting state lawmakers on board could generate a new level of support for the lake. “I am hoping we can get the resolution on the books and that it means something,” Cassio said. “If we have a couple more years of bad snowpack and rainfall, it’s going to be ugly.”

Correction: This article has been updated to change the description of algae blooms in Shadow Mountain Reservoir. The blooms have not produced toxins considered harmful to public health. In addition, the headline has been updated to reflect the persisistence of clarity issues, rather an an ongoing decline.

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