Wildfires can significantly impact our water sources

As temperatures rise, many people plan trips up north to the high country. While enjoying the cooler outdoor temperatures, we must always exercise extreme caution with fires, which can directly affect our water supply in the Valley.  

Many people do not realize that when a wildfire burns, it can lead to the destruction of vegetation that normally helps to filter and stabilize the soil. This loss of plant life can cause increased erosion and runoff during rainstorms, carrying ash, debris, and pollutants into nearby rivers, lakes, and reservoirs. All of this can negatively impact the water supply available to and treated by your water provider. Understanding this connection further highlights the importance of wildfire prevention in protecting our vital water resources.

After this very dry winter, we must do our part in preventing damaging human-caused fires, as even the most minor oversight can spark wildfires. By taking proactive measures, we not only safeguard our stunning and diverse landscapes but also protect the critical watersheds that act as lifelines for water supply throughout the Valley. These ecosystems are interconnected, and minimizing wildfire damage is essential for maintaining our natural resources and ensuring a sustainable environment for future generations.

Outside the Valley is the 8.3 million-acre watershed that channels the snowmelt and rainfall into streams, creeks, and the Salt and Verde Rivers that then flow into Lake Roosevelt and other Salt River Project (SRP)  reservoirs, which is one of the AMWUA cities’ sources of water . The health of these watersheds  is crucial for life in the desert. We face challenges not only from our long-standing drought, but also from forest fires that affect the quality and sustainability of our water supply. Moreover, Arizona’s forests are no stranger to fire. 

Since 2000, more than 3.5 million acres of forests in or around the Salt, Verde, and East Clear Creek watersheds  have been burned by wildfires, including megafires such as the Rodeo-Chediski and Wallow fires. Historically, small fires were a natural part of the ecosystem in Arizona's forests, removing excess vegetation and improving soil conditions. As forest management policies changed to suppress fires, vegetation built up. The history of fire suppression has led to the overgrowth of forests. For example, in the East Clear Creek Watershed, the number of trees grew from an average of 100 per acre, but today’s range can be up to 6,000 trees per acre.

A healthy forest serves as a storage and filtration system for water. In the winter, the canopy prevents the snowpack from melting too quickly. Slowing the snowmelt rate provides the Valley with a steady water supply in spring and summer, when it is needed most. Scorched forests expose snow to excessive sunlight, causing it to melt more rapidly and increasing the likelihood of floods. Waste from runoff settles at the base of the dams, reducing reservoir capacity and impacting water quality.

Even if a winter brings good levels of precipitation and snowpack, one might believe it would significantly benefit our forests and lower the risk of fires as temperatures rise. In some respects, this is true, as wet winters can delay the immediate effects of increasing desert temperatures. However, a winter with abundant precipitation also leads to increased vegetation, such as grass and wildflowers, which becomes fuel once dried by our scorching sun. Therefore, while the forests may seem healthy after a wet winter, high temperatures heighten the risk of wildfires.

The AMWUA cities have long recognized the critical connection between the watersheds and the Valley’s water supply. They have provided funding for ongoing efforts by SRP, the Nature Conservancy, and others to protect the watersheds and reduce the risk of catastrophic fires.

While those efforts are crucial for maintaining healthy forests, we all must do our part to protect our diverse topography by exercising care in our State Parks, during outdoor recreation, and even at home in our own backyards. Please enjoy Arizona’s great outdoors, but use extreme caution with fire and be aware that equipment and all-terrain vehicles can create sparks that are very dangerous in our arid landscape. Our diligence will safeguard our valuable forest areas and ensure the sustainability of our quality water supplies.

For 56 years, the Arizona Municipal Water Users Association has worked to protect our member cities’ ability to provide assured, safe, and sustainable water supplies to their communities. For more water information, visit www.amwua.org .