Feds start 3-day flood experiment of the Grand Canyon to improve Colorado River conditions – By Shaun McKinnon (Arizona Republic) / April 24, 2023
The Bureau of Reclamation opened the bypass tubes at Glen Canyon Dam early Monday and began three days of high water flows from Lake Powell to help improve environmental conditions on the Colorado River through the Grand Canyon.
It’s the first such high-flow experiment at the dam since 2018 and the first during spring runoff season. The goal is to move accumulated sediment downstream and begin to rebuild beaches on the river that have eroded in recent years.
The engineered flood mimics some of the river’s pre-dam flows, when snowmelt runoff from the mountains far upstream would raise water levels and redistribute sediment. Since Glen Canyon Dam’s completion in 1963, the water flowing into the Grand Canyon has carried less sediment, much of the river’s sand and other materials trapped behind the dam.