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Floods Follow Fires

Please visit the Bighorn Fire Flood Risk page for details specific to the Bighorn Fire.

Wildfires raise your flood risk by leaving the ground charred, barren, and unable to absorb water. That means even light rain can potentially turn into a financially devastating flash flood or mudflow and can occur with very little warning. This increased runoff may continue for several years after an area has burned and until vegetation is reestablished. A post-fire flood video from the Canada Del Oro Wash in Tucson, and a post-fire flood video from Cochiti Canyon in New Mexico is a good example of what can happen after wildfires. The District works with the Office of Emergency Management to provide flood alerts to residents within burned watersheds, where possible. To receive these alerts, you must sign up with MyAlerts and provide the property address(es) you are concerned about.

 

See below for important fact sheets:

Floods Follow Fires - El aumento en el Riesgo de Inundacion Despues de un Incendio

Understanding Mudflows - Las Avalanchas de lodo

Post-Fire Debris Flows

Debris flows are a common occurrence after an area has burned. As water runs downhill through burned areas, it can create erosion and undercut previously stable areas which causes large amounts of burned material (ash, sand, silt, rocks, trees) to become loose. As water and the material begin to move, the risk of damage to downhill areas increases. 

Be prepared - Create an Emergency Response Plan

Due to the topography and proximity to mountainous areas in Pima County, there is sometimes little to no warning of impending flash floods or debris flows. In the event of moderate to heavy rainfall it is best to take any emergency steps necessary to protect your life and property. Plan in advance to move away from the area and have a safety plan already in place. Plan ahead by creating an Emergency Response Plan.

Be Flood Safe

Many people do not associate Arizona with flooding, but a 2017 analysis determined that Pima County was the eighth deadliest county in the nation for flood related deaths in the preceding 20 years. That normally dry wash on your property or roadway could present a very real danger to you in times of floods. These floods can happen any time of the year - during a heavy summer monsoon storm, or during a long, slow winter storm. Flash floods can occur many miles away from the storm event that causes them. It is important to Be Flood Safe ahead of a rain storm.

Sandbags

Pima County is providing a limited number of sandbags for impacted properties, available at:

  • Department of Transportation facility at 1313 S. Mission Road (724-6410);
  • Brandi Fenton Memorial Park in the northwest dirt parking lot;
  • South side of Ina Road just east of Pima Canyon Drive;
  • In Catalina at the northwest corner of Golder Ranch Drive and Twin Lakes Drive;
  • In Summerhaven on Carter Canyon Road at the north side of Snyder Road and Lason Lane; and
  • The Town of Oro Valley is providing sandbags at Naranja Park in the Christmas tree drop off lot located just north of the Archery Range along the entry drive.

 

Flood Insurance

The time to buy flood insurance is now. Homeowners, renters and business owners need to protect themselves financially from the devastating losses flooding can bring - including after a wildfire - before the next weather event occurs.

In general, new policies for flood insurance become effective following a 30-day waiting period. However, the Biggert-Waters Flood Insurance Reform Act of 2012 provided an additional exception to this requirement related to flooding caused by post-wildfire conditions, referred to as the Post-Wildfire Exception. Under the Post-Wildfire Exception, the standard 30-day waiting period does not apply to new policies if:

  1. The covered property experiences damage caused by flood that originated on Federal land;
  2. Post-wildfire conditions on Federal lands caused or worsened the flooding; and
  3. The policyholder purchased the policy either:
    1. Before the fire containment date; or
    2. During the 60-day calendar-day period following the fire containment date

If a structure covered by flood insurance floods within the 30-day waiting period, the insurance claims adjuster will determine if the waiting period exception criteria applies and will process the claim accordingly. 

Resources

Wildfires: You Need Flood Insurance

Guidance on the Application of Post-Wildfire Exception to 30-day Waiting Period for New Policies

Preferred Risk Policies

Polizas de Riesgo Preferido

Public Service Announcement from Pima County Supervisor Ramon Valadez

Emergency Management

The Pima County Office of Emergency Management has initiated the development of the Pima County Community Wildfire Protection Plan (CWPP) in accordance with requirements of the Healthy Forests Restoration Act of 2003. Visit the Pima County Office of Emergency Management web page to view the CWPP and other emergency management related information.

The District works with the Office of Emergency Management to provide flood alerts to residents within burned watersheds, where possible. To receive these alerts, you must sign up with MyAlerts and provide the property address(es) you are concerned about.

Cleanup Requests and Complaints

The Infrastructure Management Division processes Drainage Complaints related to public infrastructure such as public drainageways, bank protection, and/or detention/retention basins.

If you have an area of concern relating to debris, mud, or blockages of public infrastructure, call The Flood Control District at 520-724-4600 to submit a cleanup request or complaint.

Media

  • "Bighorn Fire Aftermath: Experts Warn of Higher Flood risk Near Burned Areas"  - AZ Star, June 16, 2020
  • "Bighorn Fire: County Preps for Flood Risk After Fire" - KGUN 9, June 17, 2020
  • "Floods Follow Fires: Leaders Prepare for Post-Bighorn Fire Monsoon" - KOLD, June 27, 2020
  • "Floods Follow Fires" - Pima County Sheriff's Department, July 2, 2020
  • "Experts say Pima County Residents Should be Concerned About Flooding amid Bighorn Fire" - KVOA, July 2, 2020
  • "Pima County Urges Residents to get Flood Insurance Ahead of Monsoon" - KOLD, July 2, 2020
  • Public Service Announcement from Pima County Supervisor Ramon Valadez
  • "Mt. Lemmon Tour Flood Concern" - Pima County Sheriff's Department, July 10, 2020
  • "Crews Prep Tucson-area Washes Before Monsoon Flooding" - KOLD, July 15, 2020
  • "Flash Flood Carries Bighorn Fire Debris Along Channel Outside Tucson" - UK News Yahoo, July 17, 2020
  • "Bighorn Fire Debris Begins to Flood Into Washes Amid Monsoon Season" - KOLD, July 17, 2020
  • "Bighorn Fire Debris Floods Canada Del Oro Wash" - KGUN, July 17, 2020
  • "Flash Food After the Bighorn Fire in the Catalina Mountains, Tucson, AZ" - Reddit Post, July 17, 2020
  • "TFD Warns Public About Runoff from Bighorn Fire" - KOLD, July 17, 2020
  • "Video Featuring Ash-mud Slide Filmed in Pima County Goes Viral" - KVOA, July 17, 2020
  • "Pima County Prepares for More Runoff From Bighorn Fire" - KGUN, July 17, 2020
  • "Blackened Runoff Seen in Tucson-area Wash May be Just the Beginning, Flood Experts Warn" - AZ Star, July 19, 2020
  • "Streaming River of Black Sludge Floods Through Arizona" - Live Science, July 20, 2020
  • "Flash Flood in Arizona Triggers Torrent of Wildfire Debris; officials Warn of Risks After Blaze Near Tucson" - Fox News, July 20, 2020
  • "Deadly River of Black Sludge Filled with Debris Filmed Flooding Through Arizona After Wildfires" - The Irish Sun, July 21, 2020
  • "What the Hell is this River of Black Sludge Oozing as a Result of Arizona" - Inside Wales, July 21, 2020
  • "Rain triggers a flood of steaming muck near Arizona wildfire. Officials warn it can happen again" - Erie News Now, July 22, 2020
  • "Bighorn Fire Aftermath: Official Warn of Flash Flood Danger, Close Mount Lemmon" - Tucson Local Media, July 22, 2020
  • "В Аризоне опасаются внезапных селей в пострадавших от природного пожара района ( Google Translate
    Arizona fears sudden mudflows in wildfire-affected areas)" - Stormnews Russia, July 23, 2020
  • "This Oozing Black River of Sludge Makes Its Way Through Arizona" - Interesting Engineering, July 23, 2020
  • "A River of Black Sludge With Debris Flooding Through Arizona" - Nature World News, July 23, 2020
  • "A Black Stream Of 'Goo' Ripped Through This River Park In Tucson Again" - Narcity, July 23, 2020
  • "Hell Runeth Over" - The Cut, July 23, 2020
  • "Wash and Storm Drain Maintenance Throughout Pima County" - Yahoo News, July 24, 2020
  • "How Badly did the Bighorn Fire Balloon the Flood Risk" - KGUN, July 24, 2020
  • "Monsoon rains leave some Tucson businesses flooded; Pima County Flood Control Responds" - KVOA, July 24, 2020
  • "Post-Wildfire Flood Risk Expands for Tucson-area Homes, Businesses" - AZ Star, July 25, 2020
  • "Runoff from Wildfire Could Damage Many Pima County Homes" - Fox10/US News, July 26, 2020
  • "Black Sludge River Called Sediment Slug Oozes Through Arizona After Wildfire" - The Swaddle, July 27, 2020








2020 Bighorn Fire


The District is working as quickly as possible to assess the impacts of the Bighorn Fire on the flood risk to Pima County residents. Information from the District specific to the Bighorn Fire can be found on the Bighorn Fire Flood Risk page. The National Weather Service also has useful information about debris flows and flooding on their Bighorn Burn Scar webpage.

Pima County is providing a limited number of sandbags for impacted properties, available at:
  • the DOT facility on Mission Road
  • Brandi Fenton Memorial Park in the northwest dirt parking lot
  • the south side of Ina Rd. just east of Pima Canyon Dr.
  • in Catalina at the northwest corner of Golder Ranch Dr. and Twin Lakes Dr.
  • in Summerhaven on Carter Canyon Rd.
  • at the north side of Snyder Rd. and Lason Ln.

The Town of Oro Valley is providing sandbags at Naranja Park in the Christmas Tree drop off lot located just north of the Archery Range along the entry drive.