HYRUM-The Bureau of Reclamation invited the media to visit the Hyrum Dam spillway replacement construction site Tuesday to show how their work is progressing. Large earth moving equipment is dropping the elevation of the hills west of the dam some 35 feet and filling the area with rocks and boulders before pouring the concrete for the new spillway.
Rick Baxter the Provo area office manager for the U.S. Bureau of Reclamation said the Hyrum Dam is as important as larger dams in Utah.
Guest learn the new 36 inch piping that can quadruples the the discharge of the old piping did on Tuesday June 24, 2025.
“We appreciate the publics patience and understanding during this project that is needed to keep the reservoir and spillway in good working order and ensure reliable water deliveries,” he said. “The Hyrum Dam is a high hazard dam was finished being built in July of 1935. Replacing the spillway has taken lots of years and research to get to get to this point.”
For 90 years the Bureau of Reclamation has worked with South Cache Water District to maintain the dam and it has worked well. The old spillway has done its job for over 90 years but has developed voids under it causing concern for both the canal company and the federal agency.
“The taxpayers are paying 85 percent of the cost of the spillway construction and the South Cache Water Users Association is paying 15 percent,” Baxter said. “We are ahead of schedule on this nearly $116 million project.”
The existing approximately 900-foot-long spillway had been operating every single year for 90 years delivering water to the South Cache Water Users Association have.
The Bureau of Reclamation has begun construction on a new spillway at Hyrum Dam, marking a major step forward in ensuring the continued safety and functionality of this nearly 90-year-old structure.
The start of construction follows the March 2025 award of a $115.9 million construction contract to AMES Federal Contracting Group of Burnsville, Minnesota.
Ames has an office in West Valley City.
Hyrum Dam impounds Hyrum Reservoir, which stores water for irrigation and municipal use. Though Reclamation and the South Cache Water Users Association have performed maintenance over the years. The current spillway is used annually to release excess water and is approaching the end of its service life.
Crews work on the new waterway while the water flows from the current spillway into the bowl at the bottom on June 24,2024
In years past, high-volume releases through the spillway prompted around-the-clock monitoring and staging of material and heavy equipment in case emergency action was necessary.
The reservoir can hold approximately 17,746 acre-feet of water and controls the runoff of 212 square miles.
The new spillway will take 3 to 4 years to complete and will includes a new road across the dam.