Overview
- The Salt River Project increased controlled releases after heavy autumn storms, sending a powerful pulse of water through Tempe Town Lake and the Salt River in downtown Phoenix to avoid reservoir overtopping.
- Those releases are being managed with Maricopa County Flood Control and the U.S. Army Corps of Engineers routing excess flows toward temporary storage at Painted Rock, which is a flood-control basin that does not provide long-term storage.
- Local Salt and Verde reservoirs rose from about 48% full on Oct. 1 to roughly 69% full, and the surge is helping recharge groundwater beneath the Phoenix metro.
- Ecologists and city officials say the sudden flows will have mixed effects: high flows will scour some riparian vegetation but will also create pools and damp soils that benefit birds, insects, amphibians and other wildlife.
- Officials stress the limits of the event: October rains added roughly 850,000 acre-feet to Lake Powell but spring snowmelt supplies about 5 million acre-feet on average, so agencies are studying projects like raising Bartlett Dam to capture more episodic inflows rather than relying on storms to solve long-term shortages.