Project Details

Gila Bend Area Drainage Master Plan Update

Public Meetings

Currently there are no public meetings scheduled for this project.

Past Public Meetings

There are no previous public meetings for this project.
Project Manager: Christopher DiMaggio
Region: SW
District: 5 - Steve Gallardo
Phase: Planning & Studies
Description:

Gila Bend ADMP Update (2015-present)
Off-site hydrology was updated using the current NOAA 14 rainfall depths. The on-site hydrology was analyzed using two-dimensional analysis to better determine where the stormwater is ponding, especially upstream of the Gila Bend Canal. The study area for the two-dimensional analysis includes the area south of Interstate 8 (for about 1.5 miles to the south), State Route 85 to the west, Indian Road to the north, and approximately Butterfield Trail to the east. The area is about eight square miles. The revised ADMP recommends focusing efforts on the Sand Tank Wash levee, the Bender Wash overchute over the Gila Bend Canal, and the Scott Avenue Wash levee. The District is currently working with the Town of Gila Bend to develop opportunities for funding these projects.

Original Gila Bend ADMP (completed in 2002)
The purpose of the original Gila Bend ADMP was:

  1. To identify existing drainage problems and to develop corrective measures.
  2. To develop an overall drainage plan that would provide a tool to ensure that future growth provides adequate stormwater conveyance without adversely impacting existing development.
The planning area covered approximately 48 square miles bounded by the Gila River to the north, Citrus Valley Road to the west, Barry Goldwater Gunnery Range to the south, and the section line east of the Gila Bend Municipal Airport to the east. At the time the study was initiated, there had been a considerable amount of land development interest in this area. The Gila Bend ADMP provides the town of Gila Bend with structural and non-structural recommendations to properly plan for the stormwater conveyance needs of the anticipated growth.

The ADMP identified three broad recommended solutions: a set of floodwater management tools for guiding future development, flood control structures to be implemented by development, and flood control structures to be publicly funded. The third component centers on recommended improvements on Sand Tank Wash, including reconstruction of the Sand Tank Wash levee upstream of the Gila Bend Canal, and construction of a Gila Bend Canal overchute on Bender Wash, a retention basin upstream of Interstate 8 and an upstream floodwater detention facility.

Status:

The District updated the hydrologic model and the mitigation plan for the Gila Bend Area Drainage Master Plan (ADMP) watershed in April, 2015.

Recent work assignments concluded in September 2018 included the following tasks: 1) Compile publicly available data for historic storms and flooding events; 2) Conduct conceptual design analyses on the recommended alternatives to eliminate downstream adverse impacts; 3) Quantify the benefit of removing the FEMA Special Flood Hazard Area from the areas to be protected by the proposed improvements; 4) Analyze multiple storm frequencies so that the benefits of the improvements can be quantified for both large and smaller storm events; 5) Evaluate interior drainage conditions for the Scott Avenue Wash Levee; 6) Compile summary maps and findings for use in public outreach.

The District is currently working with the Town of Gila Bend to determine which potential flood control solutions offer the biggest positive impact and thus should be constructed if only partial funding is available.

Available Documents

Document Name Type Size
Gila Bend ADMP map PDF


Send us your questions or comments about this project.