White Tanks Flood Retarding Structure (FRS) No. 4


The White Tanks FRS No. 4 project received much recognition in the industry having won many project awards including the AGC Marvin M. Black Partnering Excellence Award, American Council of Engineering Companies of Arizona (ACEC), 2018 Engineering Excellence Honor Award, Water Resources, and the APWA Arizona Public Works Project of the Year for Structures $5-$25M.

Project Highlights:

  • Geotechnical Services
  • Phase I Environmental Site Assessment
  • Quality Assurance Oversight
  • Materials Testing
  • 6,800 Foot-Long, Dry Earth Dam
  • 100-Year Flood Protection

Ninyo & Moore provided geotechnical, environmental, post-design engineering, construction quality assurance oversight, and construction materials testing services for this project, which included the rehabilitation and raising of a 6,800 foot long dry-earth dam, massive flood pool grading, construction of a new 570 foot long concrete auxiliary spillway, construction of a new concrete principal spillway, and abandonment of two existing concrete inlets. The purpose of the project was to repair documented deficiencies associated with the FRS including horizontal and transverse cracking through the earthen embankment, removal and replacement of principal outlets so that they meet current design standards, embankment raising to accommodate increased floodpool storage, re-grading existing floodpool to eliminate existing dead-storage areas, and improvements to the existing auxiliary spillways. The modified structure now provides a minimum of 100-year flood protection to an estimated 4,000 current residents and 50,000 residents by year 2040; 1,000 residential and commercial properties; agricultural land, and related infrastructure; and additional residents and structures in the future as development continues to occur within the downstream benefited area.

Project Details


Flood Control District of Maricopa County


Buckeye, Arizona

NINYO & MOORE We transform today so our world is a better place tomorrow.