Floodplain Management Division

header illustration - link to pima.gov

Hot Links

General Information


Sheriff Hank Highwater





Back Button. You can also use your browser's back button.

Photo: Flooding inundates large areas of Marana and unincorporated Pima County during the January 1993 event on the Lower Santa Cruz River.


In order to minimize the threat to life and property from flooding and erosion hazards, the goal of Floodplain Management is to provide residents of unincorporated Pima County with up to date floodplain information, establish appropriate development requirements and provide timely assistance to individuals with drainage questions or concerns. This includes ensuring that any new development within the floodplain is safe from flooding and erosion hazards, does not adversely impact adjacent properties, and maintains the integrity of the floodplain.

Another important goal is protecting natural resources within floodprone areas. Floodplains typically support important riparian ecosystems and associated wildlife. These riparian areas are also important for their role in mitigating flood hazards by maintaining stable flood flow conditions, providing natural erosion control, as well as by promoting recharge into underground aquifers. As such, it is beneficial to all residents of Pima County that these critical resources are protected and maintained.

One of the ways Floodplain Management accomplishes these goals is by implementing floodplain regulations contained in the Pima County Floodplain and Erosion Hazard Management Ordinance. The Ordinance was developed to conform with the National Flood Insurance Program administered by the Federal Emergency Management Agency  (FEMA), which allows residents of Pima County to receive flood insurance. In addition, the Ordinance includes provisions regarding the construction of buildings and other man-made structures within regulatory floodplains. The Ordinance applies only to those areas prone to flooding where the peak discharge is 100 cubic feet per second or greater, or prone to sheet flooding. In other areas, the Ordinance does not apply, however other ordinances such as the Grading Ordinance may apply.

Flood Insurance

If your home is in a federally-mapped floodplain and you finance it with a loan backed by the federal government, flood insurance is mandatory. Even when not required, the District recommends purchasing flood insurance for any structure that may be impacted by flooding.

Prior to purchasing a new home or property always confirm the floodplain status of the property. You can either do this yourself by contacting our office or ask your realtor to provide the information. Additional information can be found at ABCs of Flood Insurance

Floodplain Information

The District encourages residents to become familiar with the flood related hazards impacting their property or property that they are considering purchasing.  District staff is available to discuss flood hazard issues at our customer service counters, which are located at:

97 East Congress, 3rd floor, Tucson, AZ 85701
NE Corner of Congress and Scott, 1 block east of Stone


201 N. Stone Avenue, 1st Floor with Development Services Department
NW corner of Stone and Alameda

The 97 E. Congress counter is open Monday-Friday from 8:00 a.m. until 4:30 p.m., excluding holidays. The 201 N. Stone counter is open Monday-Friday from 8:00 a.m. until 4:00 p.m., excluding holidays. For flood hazard information requests, no appointment is necessary.

In addition, some basic flood hazard information is available on-line:

A flood hazard map and other flood hazard information is available on our floodplain information page.

You may also complete a Flood Hazard Information Sheet on-line, which can be printed and mailed or faxed to Floodplain Management.  Unless requested otherwise, these forms will be faxed back to you.

NOTE: Specific questions about the flood hazard map, the Flood Hazard Information Sheet and/or the regulatory status of a wash cannot be answered via e-mail or over the phone. Please visit our office with this type of question. Other detailed questions may also require you to visit our office, where we may more accurately serve you with the wide array of resources at our disposal. If you wish, feel free to call us to determine whether or not you need to come in to our office for service.  The District phone number is (520) 724-4600.

Floodplain Use Permits

The District issues floodplain use permits in unincorporated portions of Pima County. Floodplain use permits for properties in the City of Tucson, and the Towns of Oro Valley, Marana and Sahuarita may be obtained by contacting that jurisdiction’s floodplain management office . There are currently no federally mapped floodplains within the City of South Tucson, although there may be local drainage issues that warrant attention.

A floodplain use permit is a document issued by the District that authorizes a specific improvement within a regulatory floodplain or erosion hazard area. Regulatory floodplains include areas along any wash with a base flood discharge that equals or exceeds 100 cubic feet per second, and areas subject to sheet flooding.  Virtually all man-made structures or improvements constructed within regulatory floodplains or erosion hazard areas require floodplain use permits prior to beginning construction.  These include: all structures, additions, fencing, walls, pools, drainage improvements or modifications, erosion control measures, and some temporary construction.

To assist you in planning and constructing your improvements, please review the District’s Floodplain Use Permit Application Guide.

Drainage Concerns and Compliance Enforcement

Drainage concerns involving potential floodplain violations within unincorporated Pima County should be reported to the District for investigation. A drainage violation occurs when any unpermitted activity diverts, obstructs, impedes or otherwise changes the regulatory floodplain if it creates a hazard to life or property.  Other violations may include improvement constructed not in accordance with the conditions of a permit or the Ordinance.  If a violation is observed, the owner of the property on which the problem is observed will be notified and required to take corrective action.

See the Compliance Enforcement (under construction) page for additional information regarding what constitutes a violation and what enforcement actions the District may take.

Drainage complaints enable the District to identify potential flooding problems that may warrant measures to alleviate the problem. If you observe a potential violation or if you think that a drainageway that is owned or maintained by Pima County requires maintenance, please contact the District.



About RFCD

District Overview

Photo of 97 East Congress Street
97 E. Congress


Getting a Floodplain Use Permit

Elevation Certificates

Who to Contact for Floodplain Information

Local Drainage

Neighborhood Drainage

How to Deal with Drainage Complaints

Water Harvesting on Your Property

Staying Safe

What to Do in the Event of a Flood

Some Do's and Don'ts in Floodplain Areas

Myths and Facts About Local Flooding in Pima County

Flood Insurance/CRS


Letters of Map Revision (LOMRs) within Pima County

Past Flooding Events

Flood Photos in Pima County

View a Video Clip of a Flash Flood Event on Silvercroft Wash
(.wmv video format, approx. 4 MB)

Original video filmed near Grant Road, August 27, 2003 at 2:00 p.m.


RFCD Intranet
(restricted access)

Pima County Intranet
(restricted access)

Copyright © 2003, All rights reserved


Privacy Statement / County Disclaimer / RFCD Disclaimer / RFCD Intranet (Restricted access)