Groundbreaking for the Ashurst-Hayden Diversion Dam Improvement Project

October 10, 2025

Emma Hughes

Community Newsperson

FLORENCE, Ariz. — Improvements and reconstruction of the Ashurst-Hayden Diversion Dam (AHDD), located 12 miles east of Florence, is now underway. Just upstream of the Price Station on the Arizona Eastern Railroad, the dam was constructed in 1922 after Congress authorized funds for all necessary controlling works “for the irrigation from the natural flow of the Gila River of Indian lands on the Gila River Indian Reservation and private and public lands in Pinal County,” according to the Pima-Maricopa Irrigation Project (P-MIP).

The AHDD is a unique diversion dam constructed as a 396 ft-wide and 212 ft-long slab of concrete that “floats” on the sandy riverbed, diverting water off the stream while allowing the sub flow to migrate harmlessly beneath simultaneously. While it is over 100 years old, very little has been done to maintain it.

In partnership with Hunter Contracting, P-MIP will work on improvements that include replacing flashboards and installing a new four-inch facelift to seal the front of the weir. This will allow the upstream river to be redirected into the northern portion of the forebay, lessening the amount of sediment that could enter the intake gates.

“These long overdue improvements are being made thanks to a great partnership with the U.S. Bureau of Reclamation,” said P-MIP Director David DeJong.

On Sept. 26, Gov. Stephen Roe Lewis, Community Council Reps. Duane Jackson Jr, Joseph Manual Jr, and Bureau of Reclamation David Palumbo were present for the groundbreaking at AHDD for the reconstruction. The event was marked by a ceremonial first dig, speeches from key stakeholders, and a tour of the project site, providing a glimpse of the future improvements.

According to P-MIP, the current radial gate that sluices sediment takes nearly 45 minutes to open and close. The new radial gate, however, will open and close in less than 60 seconds, a significant improvement that will prevent any unnecessary waste of water and ensure efficient water management.

DeJong added, “Over the past 25 years, there has been an average of 3,984 acre-feet of water wasted through the radial gate or over the dam that we intended to capture and put to beneficial use.” The project will significantly reduce this waste, contributing to water conservation and environmental sustainability. P-MIP is also developing a standard operating procedure to ensure that the facility is properly maintained and operated. The entire project is expected to be completed by the Fall of 2026.

“It’s really incredible to be out here and see the continued partnership with the Gila River Indian Community, so much progress being made in such a short period of time,” said Palumbo. “This facility will be really important and vital to contributing to water to the basin at large, and really a fundamental piece in a very complex puzzle.”