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The Las Conchas Fire left major damage in its wake in the summer of 2011.
The blaze scorched more than 150,000 acres, forced evacuations in Los Alamos and sent sediment and debris into the Rio Grande.
University of New Mexico researchers used water quality data from the region in a new study showing that wildfires affected 11% of streams and rivers in the western U.S. from 1984 to 2014.
The findings are especially important as wildfires increase in frequency and intensity, said Ricardo González-Pinzón, an associate professor in UNM’s Civil, Construction and Environmental Engineering Department.
“After wildfires, precipitation events start mobilizing everything that was burned and the soil that becomes exposed,” González-Pinzón said. “You get a cascading effect when all those materials enter the (river) network and affect microbial communities, insects, fish and the water that we use for drinking supply and agriculture.”
Scientists studying immediate and long-term effects of Las Conchas collected water data from a National Science Foundation-funded monitoring equipment network that existed before the fire.
The fire affected water from the Jemez Mountains to Elephant Butte Reservoir.
But it’s nearly impossible to predict where wildfires will strike. Hydrologists are often left to analyze fire-affected watersheds without real-time data.
“Whenever and wherever forest fires happen and it becomes safe to access burned sites, we should have teams ready to go to those places to start recording information,” González-Pinzón said. “Those teams can record what is changing post-fire in terms of water quality and quantity.”
The wildfire study group also included UNM research assistant professor David Van Horn; U.S. Army Corps of Engineers Albuquerque District ecologist Justin Reale; U.S. Geological Service hydrologist Grady Ball; and Pacific Northwest National Laboratory scientist Peter Regier, all of whom conducted graduate research at UNM.
The team’s research was published in April in the Nature Communications journal.
Wildfire pollution can change the oxygen and pH levels of rivers and streams.
Burned areas that don’t retain rain or snow may also cause flash flooding and affect groundwater recharge.
González-Pinzón said study results have prompted a project to develop new real-time water quality sensors with funding from the New Mexico Water Resources Research Institute.
“We need to be able to tell people living in cities downstream what dissolved and suspended materials are coming into rivers from wildfire events,” he said. “Having teams and equipment that move throughout the impacted area is like chasing and studying a moving tornado, instead of just recording what happens at one house.”
Theresa Davis is a Report for America corps member covering water and the environment for the Albuquerque Journal.