The Roundup | What’s in the water?

Test results show high iron and aluminum when Lincoln Creek and the Roaring Fork ran orange

In September 2022, Aspen Journalism reported on a local, state and federal agency investigation into what was fouling the waters of Lincoln Creek. By November 2023, findings pointed to elevated heavy metals concentrations that were naturally occurring, and in May, researchers determined that melting permafrost in the basin above, caused by climate change, is creating a “phenomenal conduit” for unlocking new contaminants. That’s part of the reason why alarm bells went off through the river community on July 16, when Lincoln Creek and the Roaring Fork River ran bright orange following a sediment release caused by the draining of Grizzly Reservoir.

Water Desk Editor Heather Sackett this week follows up on the big question on everyone’s mind: What metals, and at what levels, were flushed into Aspen’s rivers? In short: extremely high quantities of aluminum and iron. While aluminum levels already exceeded chronic water quality standards for aquatic life just below the dam on June 4 and June 25, data showed sharply increasing concentrations of aluminum and iron into the acute-risk range, particularly just below the dam, though sediment traps placed 50 yards downstream filtered out about half of the detectable particles. The potency of the release dropped sharply by the time it reached the confluence with the Roaring Fork, according to the data, but that did not stop the river as far down as Woody Creek from turning a spooky glowing orange color. The good news, such as it is, from a Colorado Parks and Wildlife official, is that the temporary event likely did little harm to fish or the aquatic environment, thanks to the relatively lower potency of copper minerals in the sediment release. See the story for Sackett’s breakdown of the event’s aftermath and water quality testing results from six sites in the watershed, visualized with a handy data mapping tool created by AJ’s Laurine Lassalle. And see below for a rundown of our past Lincoln Creek coverage.

Save the peaches by outmuscling invasive species

Sackett this week also shares how Grand Valley irrigators are working to fend off an invasive zebra mussel infestation that could be disastrous for the region’s farms, vineyards, orchards and Colorado’s famous Palisade peaches. The fast-reproducing mussels, which are native to Eastern Europe, can clog water infrastructure and are “nearly impossible” to eradicate once established. With adult mussels already impacting a reservoir northwest of Fruita, and larvae detected in the Government Highline Canal and in the Colorado River itself, water managers are seeking $4 million in federal funding for a liquid ionic copper solution that would be used in an attempt to kill larvae throughout the valley’s vast irrigation system. Palisade Irrigation District is not waiting for federal funding and plans this fall to begin the treatment that is considered to be “very safe for people and food” on its infrastructure serving 5,000 acres. 

Aspen Journalism was on the beat to provide in-depth coverage of these complex issues, to analyze findings and attend meetings. Thank you, dear readers and supporters, for making this nonprofit newsroom possible.

Grand Valley water managers have plan to outmuscle invasive species

Palisade Irrigation District plans to begin treating with copper this fall

By Heather Sackett | September 4, 2024

If these aquatic invasive species become established, it could be disastrous for the region’s farms, vineyards, orchards and Colorado’s famous Palisade peaches.

Lincoln Creek sediment release had high levels of aluminum, iron

Minimal effects on aquatic life

By Heather Sackett | August 30, 2024

Local officials, residents and environmental groups have long been concerned about water quality on Lincoln Creek and the July 16 release came at a time of increased scrutiny.

Past stories on Lincoln Creek contamination

There are always stories that need a journalist to pursue them. These Aspen Journalism investigative stories are published for you, the community, and our collaborators as a public service, thanks to the generosity of our readers and funders. Will you join them?