By Ben Gerig
During the summer, heavy rainstorms caused large amounts of sediment and organic matter to seep into Fourmile Creek, scene of the devastating Fourmile Canyon fire. In September 2010, the catastrophic inferno ripped through the canyon, flanking Boulder just to the west, causing over $217 million in damage and making it the most costly fire in Colorado history.
Following the massive fire, canyon hillsides have been stripped of their ground cover and blanketed with leftover fire retardant and ash, causing increased soil runoff into the creek—a potentially hazardous situation for local water providers, according to local resident and U.S. Geological Survey hydrologist Sheila Murphy. Old mining waste, or ‘tailings,’ piles have also been exposed.
“We could be getting increased metals from the tailings piles, probably an increase in nutrients and dissolved organic carbons as well, so it’s of concern,” said Murphy, standing creek side a few days after the one-year anniversary of the blaze.