Two recent pre-wildfire studies by the Coconino County FCD indicate that significant wildfire and post-wildfire flooding threats exist in the upper Rio de Flag watershed above Flagstaff, with significant economic impacts to the region. It has been confirmed that this is possible.
The 21,500-acre Upper Rio de Flag watershed on the west side of the San Francisco Mountains is a heavily forested region of steep slopes and drainage channels that feed into Flagstaff's main waterway, the Rio de Flag. In 2022, the Pipeline Fire burned a small portion of this watershed above Schultz Creek, causing massive post-wildfire flooding on state highways and downstream residential areas, but it destroyed a large portion of the upper Rio de Flag watershed. Parts remain vulnerable to wildfires.
“Future wildfires must be expected,” said Lucinda Andreani, Coconino County Flood Control District Administrator. “We commissioned these two pre-wildfire studies to quantify the level of risk and inform potential response strategies, and importantly, to reduce catastrophic wildfires through forest restoration. It provides insight into how to proactively reduce risk.”
The first study (Fire Severity and Post-Wildfire Flood Analysis by JE Fuller Hydrology and Geomorphology) generated flood models for several different fire scenarios for potential wildfires in the upper Rio de Flag watershed. This study fully details the potential for severe and recurrent post-wildfire flooding along the Rio de Flag River from Fort Valley through downtown Flagstaff and beyond. . The study showed that in some areas, runoff increases by up to 31 times after wildfires. More dangerous than current conditions and flooding of up to 5 feet deep in residential and commercial areas. The fire scenarios modeled in this study showed nearly 2,000 homes, more than 400 businesses, two state highways, and numerous public facilities at risk of post-wildfire flooding.
The second study, an economic impact study by the Economic Policy Institute at Northern Arizona University, uses data from the JE Fuller study to assess the potential economic impacts of wildfires and post-wildfire flooding in the upper Rio de Flag watershed. I calculated. This calculation includes everything from wildfire response and remediation to structural damage, loss of property value, business interruption, habitat loss, long-term recovery costs, and more. . According to the study, wildfires and post-wildfire flooding in the upper Rio de Flag watershed could have an economic impact of $535 million to $2.8 billion. This calculation is conservative and based on a single flood event.
“Since its founding in 2017, the Coconino County Forest Restoration Initiative has been committed to applying the best available science in the pursuit of reforestation in our county,” said District 2 Supervisor and Director said Jeronimo Vazquez, head of the department. “These studies are a step forward in that effort and represent a continued focus on the county’s top two public safety threats: wildfires and post-wildfire flooding.”
“The question is not if, but when, there will be a wildfire in our area,” said District 1 Supervisor Patrice Horstman. The district's boundaries include most of the upper Rio de Flag basin. “If we understand what we are doing now, there is no time to waste in pursuing forest restoration and other actions that can reduce risk levels. We are working closely with the U.S. Forest Service and other partners. We look forward to working together to address the threats in Upper Rio.”
When it comes to forest restoration needed in the upper Rio de Flag watershed, “we're not starting from scratch,” said Coconino County Forest Restoration Director Jay Smith. “The Coconino National Forest has already begun the forest restoration process in this area, and the District has been laying the groundwork for many years to develop regional forest restoration.”
To this end, Coconino County recently received the designation “A ” received a rating.
“This assessment will help us attract more industry partners and accelerate much-needed reforestation in the Upper Rio region and four reforestation sites,” Smith added. .
On March 5, representatives from the Coconino National Forest will participate in the district's follow-up presentation to discuss forest restoration plans for the upper Rio de Flag watershed. Information on how to attend this conference and access his recent presentation on February 27th can be found at: www.coconino.az.gov/104/Board-of-Supervisors
