It’s not only trees — wildfires imperil water too
By Emily Benson, High Country News
The Fourmile Canyon Fire, sparked by a backyard burn west of Boulder, Colo., in 2010, caused $220 million in damage and destroyed 168 homes. It also scorched nearly a quarter of a watershed that supplies water to the nearby community of Pine Brook Hills. The problems didn’t end there: Long after the blaze was put out, intense rainstorms periodically washed sediment and other particles downstream, disrupting water treatment and forcing the local water district to stop pulling water from Fourmile Creek, leaving it reliant upon water already collected in its reservoir.
“The water coming down Fourmile Creek would get so dirty that we simply would shut down moving any water (from the creek),” for days or even weeks, says district manager Robert de Haas. “If we hadn’t built the reservoir” — in 2006 — “we’d have been in big trouble.”
Now, research suggests that such water-quality problems might become more frequent across the West. Climate change is already causing a surge in wildfire activity. As a result, scientists expect to see a rise in erosion in most of the region’s watersheds in the coming decades. Sediment and ash running off burned hillsides into streams can clog reservoirs, smother fish and disrupt municipal water supplies.