Project Details

Lower Gila River Floodplain Delineation Study

Public Meetings

Currently there are no public meetings scheduled for this project.

Past Public Meetings

• 9/25/2014
• 9/24/2014
Project Contact: Felicia Terry
Region: W
District: 5 - Steve Gallardo 4 - Clint L. Hickman
Phase: Floodplain Delineation

The Flood Control District of Maricopa County is conducting a detailed Floodplain/Floodway Delineation Study along the Gila River from Airport Road downstream to the Painted Rock Dam Reservoir (approximately the 307th Avenue alignment).

The study will use detailed topographic mapping and technical analyses to re-evaluate the extent of floodprone areas along the 41-mile study reach. The results will be a re-delineation of the floodplain and floodway boundaries.

When completed, the study results will be used by the District for floodplain management purposes. The results will also be submitted to FEMA for approval and incorporation into FEMA's Flood Insurance Rate Maps (FIRMs) for its National Flood Insurance Program.


Depth Map:


The study was submitted to FEMA on December 8, 2015. FEMA completed its technical review and approved the study in October 2016. The public review and technical appeal period is from February 20, 2019 to May 20, 2019. Anyone who believes they have better technical data may submit that data to FEMA for review and possible revision of the floodplain maps during the appeal period. The FCD will be submitting the Lower Gila River Overflow Floodplain Delineation Study (Overflow) as an appeal of the delineation in the area covered by the Overflow study. The FCD anticipates the final updated maps to be published by FEMA in mid to late 2020. The study will remain on the FCD website as a "pending" floodplain until it becomes effective (published) on FEMA's maps. "Pending" floodplains are regulated the same as effective floodplains. View the "pending" floodplain on the "Current and Pending 100-Year FEMA Effective Floodplain Maps" at the following link:

View the pending floodplain.

Depth Map:

View the Depth Map.

Available Documents

Document Name Type Size
0. Newsletter - Gila River Initiatives (Jan 2018) PDF 706 KB
1. Mannings Sensitivity Report (Nov 2014) PDF 72.4 MB
1a. Lower Gila River FDS Technical Report - DRAFT (Nov 2014) PDF 682 MB
2. Public Meet_PowerPoint Presentation Slides (Sep 2014) PDF 3.21 MB
3. Public Meet Exhibit_Lower Gila River Reach 2 (Sep 2014) PDF 43.2 MB
4. Public Meet Exhibit_Lower Gila River Reach 1 (Sep 2014) PDF 43.2 MB
5. Public Meet Exhibit_Gila River Buckeye Slough (Sep 2014) PDF 42.2 MB
6. Public Meeting Comment Sheet (Sep 2014) PDF 93.3 KB
7. Letter to property owners (March 2014) PDF 1 MB
8. Letter to property owners (Jan 2013) PDF 1.12 MB

Send us your questions or comments about this project.