Could restoring a river be as simple as reconnecting its flow?
Just two years ago, the Colorado River near Granby, Colorado, looked more like a shadow of its former self. Decades earlier, the construction of Windy Gap Reservoir drastically altered its natural course, leaving fish populations struggling and anglers reminiscing about better days. But today, thanks to an ambitious restoration project, native trout and other aquatic life are returning, bringing fresh hope to both the river and the community around it.
In May 2025, biologists from Colorado Parks and Wildlife (CPW) released the results of an electrofishing survey along a newly constructed mile-long channel: approximately 848 brown trout and 221 rainbow trout now call it home. Remarkably, these thriving fish populations weren’t stocked, they returned naturally, underscoring the river’s potential resilience when given a chance.
Built in 1985, the Windy Gap Reservoir served vital water needs for northern Colorado’s growing population. But with it came unintended consequences. The reservoir disrupted natural water flows, sediment piled up, water temperatures rose, and insects essential to trout survival vanished. Sculpin, a small fish critical to the aquatic food chain, disappeared from nearly 30 miles of the Colorado River.
Dave Parri, a fishing guide who’s spent over three decades on these waters, remembers when trout were abundant and insects swarmed like snowflakes. By the 1990s, those vibrant scenes faded. Parri, among others, watched helplessly as trout populations collapsed.
In response, an extraordinary collaboration emerged among CPW, Northern Water (the reservoir’s operator), local governments, and environmental groups, including Trout Unlimited. They envisioned the Colorado River Connectivity Channel, a $33 million project aimed at reconnecting the river’s disrupted flow and revitalizing its ecosystem.
Completed in fall 2023, the Connectivity Channel has begun reversing decades of ecological harm. Not only trout but native sculpin have returned, an encouraging sign of renewed ecological balance.
“It’s incredible to see adult trout thriving without stocking,” remarked Jon Ewert, a CPW aquatic biologist. “The habitat improvements allowed fish from upstream and downstream to naturally repopulate this section.”
This transformation reflects deep collaboration and compromise. Kirk Klancke, president of the Colorado River Headwaters Chapter of Trout Unlimited, emphasized the importance of sustained partnership: “Long-term collaboration is key to keeping rivers alive. Grand County’s effort can inspire similar initiatives across the region.”
Initially resistant, Northern Water gradually embraced the project after research showed how significantly Windy Gap Reservoir affected river health. Jeff Stahla, Northern Water’s spokesperson, acknowledges the shift in perspective: “We’ve learned much about river ecosystems. Collaboration with communities has significantly improved our approach.”
Restoring river health isn’t just an ecological victory, it’s vital for local economies reliant on outdoor recreation. Tourism contributes to nearly half of all jobs in Grand County, making thriving rivers essential.
Former fishing guide Wayne Balnicki witnessed firsthand the economic ripple effects when trout populations dropped. “It’s hard guiding fishing tours when fewer fish are available,” he noted. “Reviving the river means reviving livelihoods.”
With sculpin and trout returning swiftly, optimism is growing. CPW predicts continuing improvements as native vegetation establishes along the new riverbanks. Public fishing access, currently restricted, will reopen once the landscape recovers fully.
The Connectivity Channel illustrates how communities, environmentalists, and water providers can work together effectively. Stakeholders hope the model will guide similar restoration projects across the Western U.S., where water diversion often strains rivers and their ecosystems.
Dan Kowalski, CPW’s aquatic research scientist, calls the rapid return of aquatic life “a significant conservation milestone.” Trout and sculpin populations are indicators of a healthy ecosystem, suggesting broader benefits to biodiversity.
With each passing season, the Colorado River Connectivity Channel demonstrates nature’s remarkable capacity to rebound. Anglers like Parri and Balnicki hold renewed optimism, envisioning days ahead when the river returns to its former glory, or perhaps surpasses it.
As Parri puts it, “Nature always finds a way back, given half a chance.”
Could the Colorado River’s remarkable comeback inspire your local river’s restoration?
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