Wildfires have the potential to impact water and wastewater utilities by more than just burning their infrastructure and introducing harmful chemicals into pipes, as has been observed in recent incidents. As happened following a large wildfire in New Mexico last year, a city’s water utility was unable to treat the water due to large amounts of ash and debris, leading the local and state governments to declare emergencies.

The Hermit’s Peak Fire burned over 300,000 acres near the town of Las Vegas, New Mexico. It was the state’s largest wildfire, followed in subsequent months by flash floods that inundated the city’s utility with large amounts of contaminated water. Unable to treat the water and with dwindling supplies, the city rapidly installed a temporary pre-treatment system, helped by $2 million provided by the New Mexico government. It is still propping up the overstrained filtration system while the town applies for federal funds for a permanent water treatment facility the mayor estimates could cost as much as $200 million. While this may seem like a rare event, wildfires have become more common and more destructive. When they're followed by heavy rains, as happened in New Mexico and other places, municipal drinking water systems can find they’re unable to treat the scale of contaminated water. They must often pay astronomical costs to augment, repair, or replace entire water distribution systems. With risks growing, researchers say at-risk areas must plan ahead to act quickly and communicate clearly about water issues to fire-hit residents. Read more at Yale Climate Connections.