Salinas Valley water projects might trip up on a threatened fish: steelhead trout.

In Monterey County, there has been much talk over the last two decades about a single species of fish, and thousands of man-hours and millions of dollars have been spent to help save it: Carmel River steelhead trout.

Yet in that same time period, there has been far less talk about the steelhead in the Salinas River, which – like their Carmel River cousins – have protections under the Endangered Species Act.

Going forward, don’t expect the old pattern to hold: On June 2, The Otter Project sent a 19-page letter to a host of regulatory agencies – including the Monterey County Water Resources Agency and the National Oceanic and Atmospheric Administration – indicating the nonprofit intends to sue in 60 days if steps are not taken to address alleged violations of two federal laws, the Endangered Species Act and the Clean Water Act.

“We’re not saying they have to fix it right now,” says Steve Shimek, chief executive of the nonprofit. “Within 60 days, they need to tell us what they’re going to do to fix it. If they don’t, we intend to sue them.”

In 2014 and 2015, no steelhead returned to the river.

The letter paints a bleak picture of the modern trajectory of Salinas River steelhead, from 4,750 returning to the river in 1965 to just 43 in 2013. In 2014 and 2015, no steelhead returned at all.

The alleged violations stem from MCWRA’s multifaceted Salinas Valley Water Project. In 2007, the Army Corps of Engineers granted the county a permit to build the rubber dam in North Marina, but as a condition of that permit, the county must adhere to several requirements spelled out by NOAA scientists.

Among those conditions are a minimum flow requirement of 60 cubic feet per second from the Nacimiento Dam, which The Otter Project alleges the county violated in 2014 and 2015.

The letter also states the county has failed to install a fish screen at the rubber dam, failed to adequately reduce pesticides in the river by 50 percent, and hasn’t carried out water quality and steelhead monitoring. Under the county’s federal permit, those were all required actions.

Shimek says that with a handful of water projects in the pipeline, including an interlake tunnel and Pure Water Monterey, time is of the essence to ensure the steelhead are protected.

“What do steelhead need, not only to exist, but to recover?” he says. “Once we establish that, it’s appropriate to evaluate things like the interlake tunnel.”

NOAA officials declined to comment, citing pending litigation, and a county spokesperson says the letter is under review by county counsel.