Bighorn Fire Flood Risk

The Bighorn Fire has increased the risk of flash floods and mudflows in the foothills of the Catalina Mountains. Pima County residents living adjacent to washes downstream of the Bighorn Fire burn area should be aware of the increased risk of flooding due to the fire and take appropriate steps to mitigate that risk. Loss of vegetation and physical changes to the soil leave burned areas prone to increased runoff and erosion. This combination can cause flash floods and mudflows to flow faster and with more volume than normal flows during a typical monsoon storm. These flows, which can include ash, mud, and vegetative debris, increase flood risk for those who work and live in downstream areas.

Flash floods may overtop wash channel banks and cause damage in adjacent areas, even beyond the limits of the regulatory flood. After the Aspen Fire on Mount Lemmon in 2003, flash floods and mudflows resulted in at least one reported fatality and caused extensive property damage in watershed areas downstream of the burn area. 

What can you do?

Sign up for MyAlerts. The Pima County Office of Emergency Management’s MyAlerts (http://myalerts.pima.gov system allows the Regional Flood Control District to provide near real-time flood alerts to Pima County residents within certain watersheds. Residents who sign up for MyAlerts using addresses within these watercourses will receive messages about flood events in their area. This warning system is the most effective way for the Flood Control District to notify residents about flood events. Find additional information about the MyAlerts Flood Alert Messaging webpage at www.pima.gov/floodalerts.

Get Flood insurance. Disaster relief for private property is almost unheard of and after the flood is too late to get flood insurance. The Flood Control District recommends that you acquire flood insurance immediately. The cost does not change due to the fire and you may be surprised how inexpensive it is, especially if your structure is not within a FEMA Special Flood Hazard Area. Ask your insurance agent about a Preferred Risk Policy.

Protect your structure(s). A common response to the threat of flooding is to protect ones entire property. However, frequently some of that land is necessary to convey flows and obstructing the flow path risks adversely affecting other properties. The best course of action is to identify ways to protect your residence from flood damage. The use of sandbags in the doorways, or small diversions just upstream of the residence is usually the most effective way to protect the residence while leave the rest of the property open to flow. Protecting more than just your structures may cause harm to your neighbors and leave you open to civil lawsuits. It may also be a violation of the Floodplain Ordinance, leaving you open to enforcement action and fines.

Create an Emergency Response Plan. An Emergency Response Plan should include preparing “go bags” to help you and your loved ones get out of harm’s way quickly, the fastest route to high ground and safety, and keeping in contact with friends and family.