The United States Army Corps of Engineers reassure that Lake Success and Lake Kaweah are not going to breach dams, even amid current storms
TULARE COUNTY – After the recent deluge and atmospheric river poured over the valley, officials reassure residents that local dams are expected to withstand the storm.
Both Lake Success and Lake Kaweah are nearing capacity due to the recent rainfall in Tulare County, according to a press release from the Tulare County Sheriff’s office. To remedy this, Lake Success’s dam spillways have opened. Lake Kaweah may also be opening their spillways after the next incoming storm. These spillways are designed to ensure the vast flows of incoming water do not damage the dam structure, according to Ryan Watson, project manager of the United States Army Corps of Engineers.
“[The dam] is safe at [capacity] level, but that doesn’t mean that it’s unsafe when it’s below or above it,” Ken Wright, public affairs specialist of the Army Corps of Engineers said. “The dams are not in danger of being damaged.”
Wright said that their teams are closely monitoring incoming water runoff, reservoir capacities and conditions of each dam structure multiple times a day. They will be informing the public with all information as it comes in. The outflow of water from the dam outlet is approximately 4,200 cubic feet of water per second as of Tuesday morning, and is expected to increase to approximately 7,800 cubic feet of water per second by Wednesday afternoon. The release of water will decline into the weekend as the inflow recedes, according to Wright. The outflow fluctuates to accommodate unregulated downstream flow. Forecasted rain and increasing water outflow may cause localized flooding downstream of Terminus Dam.
“Terminus Dam is designed to hold flood waters coming down from the Kaweah River. Our spillway has a very unique design,” Watson said. “In order for the dam to be breached, inflows would have to be well over 300,000 [cubic feet of water per second]. For some perspective, the Kaweah River didn’t reach 50,000 [cubic feet of water per second] in Friday’s storm.”
The capacity at Lake Kaweah is 185,630 acre feet. As of 1 p.m. on March 14, current water storage is at 146,482 acre feet. The Terminus Dam spillway is a “fusegate” spillway, and Watson said they are named this because they act like fuses in an electrical system. The fusegate spillways will “sacrifice” themselves to relieve pressure from the dam, and go off in a sequence. The first fuse sacrifices itself until water exceeds 200,000 cubic feet per second. If the water continued to rise after the first fuse goes, then the second would begin releasing water. This allows for a safe way to keep water down and to protect the dam.
Both dam structures at Lake Success and Kaweah Lake are stable, in good working condition and operating as designed, according to TCSO’s press release. Residents can expect to see water activity over the spillways at each dam, which is normal. The press release also noted that water activity and releases over a spillway are not an indication of dam failure, but are part of the dam’s intended operation.
Watson said that the situation is dynamic and changing as storms continue to loom overhead, and this causes the amount of water being released to change. They are currently not expecting any flows over the fusegates until late Wednesday night or early Thursday morning. They are also expecting inflows to reduce by then, making any flows over the spillway minimal.
County and city emergency operation centers are activated and closely monitoring potential for flood impacts as well. Officials urge people to be prepared for more potential flooding, especially those who reside near waterways.