Tag: floods

Thousands of fish die in Colorado, amid flood recovery projects

Thousands of fish die in Colorado, amid flood recovery projects

Cars drive on County Road 43, in Larimer County, Colorado, past a road reconstruction project after the 2013 floods. Some bridge-building may have contributed to a fish die-off (Photo via Larimer Country Road 43 Public Infrastructure Project)

In March 2016, a resident of the small Colorado towns of Drake and Glen Haven — situated within northern Colorado’s Big Thompson River Canyon — reported noticing funky gray water in a side creek of the river and a murder of crows picking at a few dead fish. A few days later, March 7, a large plume of more cloudy water ran down the Big Thompson, leaving behind a massive fish kill. Colorado Parks and Wildlife officials now confirm that more than 5,600 fish, mostly rainbow and brown trout, died in the Big Thompson and its North Fork, and are blaming concrete from a bridge reconstruction project, part of the state’s massive recovery and reconstruction effort following the devastating September 2013 floods.

The die-off is alarming news for the Big Thompson, a popular fly fishing river among tourists and locals, which formerly generated an annual $4.3 million for the region. Larry Rogstad, Colorado Parks and Wildlife Area Manager, says the “iconic” fishery is also important as one of the only rivers in Colorado with wild rainbow trout free of whirling disease. The 2013 floods had already knocked back the river’s fish populations, and Rogstad estimates the recent incident killed more than half of the estimated fish within an eight-mile-long downstream stretch of river.

Jeff Crane, a consulting river hydrologist and restoration expert, says he’s surprised at the magnitude of the fish kill. But he adds that it’s also important to recognize the complexity and ambition behind recovery projects aiming to improve rivers’ natural functions and flood resiliency.

For instance, the previously straightened river now bends and courses through the middle of the canyon, while several new bridges are replacing buried culverts that typically get blocked or exceed capacity during flooding. “We’re actually ‘building’ a whole new river,” says Crane, a proponent of “natural channel design” that mimics natural landforms and uses less grouted rock, or riprap, than conventional flood-protection measures. Despite the fish kill, the local restoration should improve fish and aquatic habitat and reduce flooding damage in the long run, Crane says.

“Thousands of fish die in Colorado, amid flood recovery projects”

High Country News, April 26, 2016

The Road to Flood Recovery

The Road to Flood Recovery

Hwy7 floods CDOT
State Highway 7 near Lyons, Colorado following Sept. 2013 flooding. (Courtesy Colorado Department of Transportation)

In September 2013, driving rains flooded North St. Vrain Creek to nearly 10 times its typical volume and caused it to rise more than 5 feet in barely 24 hours, chewing up sections of U.S. Highway 36, the adjacent roadway between Lyons and Estes Park, Colorado. In Apple Valley, a small side canyon off the highway, the swollen river uprooted and inundated houses and buried cars as it carved a brand new channel.

The close proximity of houses and the highway to the river not only left them vulnerable to damages, but also compromised the natural function of the North St. Vrain’s floodplain.

With last fall’s floods, opportunity has followed tragedy. Recovery efforts have meant a chance to upgrade and restore both river systems and infrastructure, which haven’t always functioned in harmony. Initiatives to protect property and lives in the short term are feeding into long-term plans to reduce flood risks while also restoring the natural patterns and functions of rivers.

The vision is a herculean one, requiring the coordination and cooperation of scores of federal, state and local government agencies, businesses and conservation groups, and thousands of landowners—all with slightly different interests but a common goal of improving flood resiliency. The project unfolding along Highway 36 is a prominent, initial example of what that cooperation might look like and the results it could produce.

“Race to Recovery”

Headwaters Magazine, Summer 2014