Two environmental groups have sued the operator of the Twitchell Dam east of Santa Maria, seeking to change the timing, duration, and intensity of water releases to benefit an endangered fish.
The San Luis Obispo Coastkeepers and Los Padres ForestWatch filed the lawsuit in Santa Barbara County Superior Court, with an eye toward preventing the Southern California steelhead trout from becoming extinct
The lawsuit, naming Santa Maria Water Conservation District as a defendant, contends California law has required dam operators to release sufficient water to keep fish stock in good condition.
The environmental groups are not seeking additional Santa Maria River stream flow releases, Kuyper said, adding they seek water releases timed differently to assist the steelhead.
“They just have a small window during and after storms where they make the 30-mile journey to the headwaters at Sisquoc,” said Jeff Kuyper, ForestWatch executive director.
The goal is to have Twitchell releases better match the historical flows in the Santa Maria River, he added.
Since Twitchell Dam’s construction in the 1950s, the Santa Maria Valley Water Conservation District’s management prevented flows from the Santa Maria River to the Pacific Ocean, limiting migration and stranding endangered steelhead in a channel with little water, the environmental groups contend.
“The construction of Twitchell Dam has altered the condition of fish populations below the Dam from historically good to currently poor,” the lawsuit says.
Migratory steelhead in the Santa Maria River below Twitchell Dam “are now very rare, consisting of a few stragglers even in the highest flow years,” the lawsuit said.
Twitchell Dam sits on the Cuyama River, about 66 miles from its headwaters and about 6 miles from its junction with the Sisquoc River, where the two form the Santa Maria River.
The dam and reservoir, which holds up to 224,300-acre-feet of water, provide flood control while also replenishing the groundwater basin in the Santa Maria Valley.
The lawsuit doesn’t blame the dam for blocking steelhead migration, instead contending that the district limits the timing and quantity of the water flow in the Santa Maria River, preventing passage between the Pacific Ocean and Sisquoc spawning habitat.
“Our lawsuit seeks to bring the Santa Maria Valley Water District out of the 1950s and into the 21st century,” said SLO Coastkeeper Gordon Hensley. “Releasing water for fish migration will have virtually no impact on agricultural or domestic supply—our experts estimate 4 percent of reservoir water would be affected.
“Santa Maria can have both steelhead and its water supply with straightforward changes to water management,” Hensley added.
Santa Maria Valley Water Conservation District representatives did not return calls for comment.
Steelhead are considered one of the most endangered fish species in the United States, the environmental groups said, adding that the rainbow trout spawns in coastal streams before migrating to the Pacific Ocean shows the health of local waterways.
“Endangered steelhead have nearly disappeared from river systems throughout the Central Coast,” said Kuyper. “Today’s legal action seeks to restore one of our region’s most prolific fisheries while maintaining reliable water supplies for our farms and communities.”
The Santa Maria groundwater was the focus of massive lawsuit involving hundreds of defendants amid a dispute regarding rights to the groundwater basin.
Kuyper said the steelhead lawsuit should not conflict with the water rights case.
“I think our lawsuit was narrowly crafted looking at Twitchell Dam and how it can better comply with state law that requires dam operations to provide stream flow,” he said.
— Noozhawk North County editor Janene Scully can be reached at jscully@noozhawk.com. Follow Noozhawk on Twitter: @noozhawk, @NoozhawkNews and @NoozhawkBiz. Connect with Noozhawk on Facebook.