Human resources

Wildfires pose serious risks to western water resources

Based on analysis of scientific research and evidence from wildfire prone regions around the world.

While large and severe wildfires visibly harm air quality, infrastructure, and landscapes, they also damage watershed ecosystems by killing vegetation and altering soil. This can lead to a series of “cascading disasters”, according to the report, which include flooding, landslides and debris flows during heavy rains following a fire, as well as changes in the amount of water in groundwater reservoirs, especially in California. —for drinking water and agriculture.

“As people continue to settle and build communities in forest areas, the burning of cars, homes and other infrastructure during wildfires releases toxic compounds that can contaminate water supplies. write UCS fellow Carly Phillips and Kristina Dahl, senior climatologist for the UCS Climate and Energy Program. “Across the United States, public drinking water systems downstream of large wildfires experienced high concentrations of compounds such as nitrates and arsenic, which in some cases exceeded levels considered safe. by the Safe Drinking Water Act.”

The report notes that large. severe fires are expected to continue due to human-induced climate change without a rapid reduction in heat-trapping emissions. In the meantime, it recommends actions to reduce the severity of forest fires and protect water supplies by clearing excess vegetation in forests through thinning and controlled burning, removal and replanting of wood after fires. fires to reduce erosion and runoff, and burying of power lines if done as part of a holistic approach that addresses forest conditions, climate change and grid resilience. At the local level, the report suggests adaptation measures to build the resilience of water infrastructure, including diversifying water sources and investing in flexible treatment capacity and water quality monitoring.

“We need to make these changes in the western United States to prepare our water systems for climate change and its predicted impacts, especially in California, Colorado, Oregon and Washington, where wildfires from recent years have highlighted the vulnerability of our forests and our water. supplies,” the authors write. “Unless we limit human-caused climate change and adapt to the increasing incidence and severity of wildfires, Western water supplies will continue to be increasingly threatened in the future. »