A Direct Line From Forest Management to Water Supply

Urban water suppliers have had to learn quickly that fire ecology is a major concern in maintaining a secure water supply system.

2 minute read

March 15, 2019, 11:00 AM PDT

By James Brasuell @CasualBrasuell


Sangre de Cristo Mountains

arak7 / Shutterstock

Jasques Leslie begins this story about the connections between watershed and fire protection with an anecdote from the 2011 Las Conchas Fire in New Mexico, which tripled the size of the previously largest wildfire in state history.

"But the fire’s full impact didn’t register until nearly two months later, when a thunderstorm in the Jemez Mountains washed tons of ash and debris into the Rio Grande River, the water source for half of New Mexico’s population and for a major agricultural area. Only an inch of rain fell, but the debris flows the storm generated turned the river black and dumped ash, sediment, and tree and shrub remnants into a major reservoir, requiring a costly cleanup."

According to Leslie, New Mexico is far from alone in learning this lesson: "megafires in similarly dry and overgrown watersheds have ended up contaminating downstream water supplies in numerous areas throughout the western United States, including Phoenix; Denver; Flagstaff, Arizona; and Fort Collins, Colorado. Downstream water managers serving millions of urban residents have learned that the security of their water supplies is tied to the health of upland watersheds that may be hundreds of miles away."

Now, the safety of the water supply is an outcome of for management—just as historic droughts and insect infestations have required completely new approaches to forest management.

Turning attention back to New Mexico after the Las Conchas Fire, residents in the Rio Grande watershed worked with the The Nature Conservancy to establish the Rio Grande Water Fund. That public-private partnership comprises 73 contributing members, including "government agencies at all levels, foundations and other NGOs, local water utilities, and local businesses and residents."

"Together they raised enough money for a 20-year program to restore 600,000 forest acres — enough to support the resilience of the entire central and northern New Mexico portion of the Rio Grande watershed. They have already restored 108,000 acres, and are racing to complete the job before another megafire occurs," according to Leslie.

Tuesday, February 19, 2019 in Yale Environment 360

"Planetizen federal action tracker" logo superimposed over black and white image of US Capitol dome.

Planetizen Federal Action Tracker

A weekly monitor of how Trump’s orders and actions are impacting planners and planning in America.

October 28, 2026 - Zachary Whalen

A car drives through a puddle, making a large splash. Rain pours down.

California plans to bury El Niño’s downpour

If the state plays its cards right, it may be able to store a billion acre-feet of El Niño’s water in aquifers.

October 28, 2026 - Grist

Lake Powell with much of the water evaporated.

Desperate measures: Advocates weigh draining Lake Powell to fill Colorado River

Draining the reservoir could reduce evaporation losses by a couple hundred thousand acre-feet.

October 30, 2026 - Yale Environment 360

A Firefighter sprays water from a hose at a tall blaze.

US buildings threatened, destroyed by fires set to triple by 2060

Researchers found a high fire risk for socioeconomically vulnerable neighborhoods in the American West.

November 4 - Inside Climate News

People cross a crosswalk in Los Angeles.

LA residents may be allowed to paint their own crosswalks

Councilwoman Katy Yaroslavsky put out a motion instructing the Los Angeles Department of Public Transportation to study the feasibility of allowing volunteers to paint crosswalks.

November 4 - ABC7

Two women walking on the sidewalk in Dallas.

Dallas moves to overhaul its zoning code

The city's zoning reform will allow more multi-family and mixed-use developments.

November 4 - Yahoo News