According to USBR, a 2003 Comprehensive Facility Review of the dam raised concerns about the 70-year old facility’s stilling basin, the integrity of the spillway chute and voids along the lower ends of the spillway walls.
Current investigations at Hyrum, an earthfill dam constructed in 1934–35 on the Little Bear river, began in January with the removal of snow. USBR anticipates repairs to include inserting filtered drain pipes into the existing toe drain system, drilling holes through the spillway floor and wall slabs, injecting sand or grout slurry into voids and the monitoring of floor slabs for movement.
The dam also received a number of repairs in 1990 under a rehabilitation and betterment programme, which included refurbishment of the radial gates, hoists and gate electrical control system and spillway maintenance.
