Posted on September 9, 2026
By Shawn Davis
SAN BERNARDINO, Calif. — The U.S. Army Corps of Engineers Los Angeles District led a tabletop exercise Aug. 20 in collaboration with other local, state and federal agencies to test coordinated emergency management response efforts during a Super El Nino extreme weather event.
The tabletop exercise centered around the Seven Oaks Dam in San Bernardino and included emergency management responders and representatives from San Bernardino, Riverside and Orange counties; the California Governor’s Office of Emergency Services; California Department of Water Resources; and the Federal Emergency Management Agency.
Southern California is predicted to receive significant weather events this winter because of a possible Super El Nino year, which can impact the area, causing extreme rain, flash floods and mudslides.
A Super El Nino is defined as a phase where the sea surface temperatures rise by 3.6 degrees Fahrenheit or more above the normal season average. This causes ocean warming shifts and atmospheric responses, shifting global jet streams. For Southern California, this shifts the jet stream southward, which can cause back-to-back atmospheric rivers into the region, between December and March.
During the tabletop exercise, the team created a “Super El Nino” atmospheric river scenario to test emergency responses, ensure seamless coordination during high-water events and strengthen joint operation capabilities between partner agencies on how they would coordinate a unified response to a worst-case scenario, starting at the Seven Oaks Dam.
The dam was built by the U.S. Army Corps of Engineers and is maintained and operated by the San Bernardino County Flood Control District. Its multi-jurisdictional location, which includes San Bernardino, Orange and Riverside counties, provided an ample opportunity to test each agency’s readiness and emergency response capabilities during the exercise.
Grant Adams, USACE Los Angeles District lead project planner, welcomed participants to the exercise and provided a brief background about the Santa Ana River Basin, which includes the Seven Oaks and Prado dams, as well as four other dams and a network of channels and levees.
As the exercise began, the team discussed how they would respond to a range of compounding factors, including heavy rainfall, flooding and flood-after-fire debris flows.
Discussion during the session and after-action review also focused on how participating agencies would communicate with each other if events disrupted communication infrastructure and how agencies would determine and communicate evacuation plans and flood-fighting support across multiple jurisdictions.
Col. Josh Bost, who took command of the LA District at the end of July and was participating in his first exercise with the district, told the team it was a great start for preparing for this type of emergency.
“The more often we do this, the more often we get together, the stronger the relationships are going to be,” Bost said, “and the better prepared we’re going to be if a disaster does strike.”
The U.S. Army Corps of Engineers Los Angeles District conducts exercises like this annually to ensure emergency responders are coordinating and prepared before an emergency or disaster strikes.
