In many places around the country, the threat of drought, major storms, or other extreme weather events has created a need for more efficient forecast data. The U.S. Army Corps of Engineers (USACE) relies on accurate weather projections to most effectively manage its 419 dams, especially in the face of unpredictable climate patterns, fierce competition for water resources, and rising costs.

The U.S. Army Engineer Research and Development Center’s (ERDC) Coastal and Hydraulics Laboratory pioneered Forecast-Informed Reservoir Operations (FIRO) to optimize that efficiency. FIRO is a revolutionary water management strategy that analyzes cutting-edge weather and streamflow forecasts and creates a flexible “FIRO space” in a reservoir that allows operators to adjust water level based on expected conditions, rather than adhering to uniformly mandated level.

In the case of an impending drought, FIRO retains more water in the reservoir to preserve the supply. In water-scarce regions like the arid Southwest, or parts of Colorado and California that struggle with their water supplies, the constant need for more water is compounded when dam releases are inefficient and wasteful. FIRO allows those dam operators to preserve as much water as possible because of the more useful data it collects.

FIRO can also release water to mitigate flood risks. Before a powerful storm makes landfall on the East Coast, for instance, FIRO data can help dam operators decide to preemptively release water to create more reservoir capacity and limit flooding. On top of the FIRO spaces that maximize efficiency, FIRO can boost water supply, improve flow management and safety, increase infrastructure efficiency, and adapt to weather extremes.

FIRO came about from a unique collaboration among federal agencies (USACE, National Oceanic and Atmospheric Administration, and U.S. Bureau of Reclamation), academic institutions, and local water agencies. After a Cooperative Research and Development Agreement (CRADA) was signed and pilots were successfully conducted, USACE districts began incorporating FIRO principles into official water control manuals.

Thus far, the impact is undeniable. In Northern California, at Lake Mendocino and Lake Sonoma, FIRO helped conserve $29 million worth of water in 2024 alone, affecting 58,000 homes. The savings pattern over a few years at these lakes show that FIRO becomes more effective the longer it is implemented and is useful despite weather whiplash (a phenomenon marking alternating periods of extreme drought and heavy precipitation, for which FIRO was present in Northern California).

In Southern California, FIRO at Prado Dam — where the initial CRADA was established between ERDC and the Orange County Water District in 2018 — conserved $6.1 million worth of water for 12,200 homes in 2024. Prado Dam is primarily a dry dam used for flood control, so this example showcases FIRO’s adaptability to different hydrological contexts. Though FIRO was conceived for forecasting and flow management, it has proven to have several other unique benefits. For instance, FIRO’s enabling of more nuanced water releases supports natural ecosystems, like fish species sensitive to river flow timing. The use of hurricane hunter aircraft by FIRO to gather data has improved forecasting accuracy by as many as three days, which is a net benefit to the country and its inhabitants.

Finally, FIRO is a highly cost-effective solution to water management. By optimizing existing infrastructure, FIRO provides benefits equivalent to building new dams or expanding current ones at a fraction of the cost. One example is the Oroville and New Bullards Bar project, where FIRO implementation will provide flood protection equivalent to a proposed 240,000 acre-feet capacity dam that was never built, saving taxpayers hundreds of millions of dollars.

Modern water management is a complex challenge, but FIRO has proven itself a malleable, capable, and cost-effective tool. Now, the USACE is evaluating FIRO’s applicability for all of its dams across several types of dams and climates, in places affected by severe — and severely different — types of weather and surrounding environments.

This technology received a 2025 FLC Impact Award.