In March, the demolition of four dams caused a sharp increase in sediment and heavy metal pollution downstream. Residents then raised concerns about elevated arsenic and lead levels with the Siskiyou County Board of Supervisors.

Supervisors voted 4-1 to declare a local state of emergency and sent an emergency alert to Governor Gavin Newsom’s office.

This request was rejected earlier this month.

A letter from the Governor’s Office of Emergency Services dated August 8 states that numerous safeguards have been put in place “to ensure that the expected short-term impacts of the Lower Klamath Dam removal project do not have adverse human health effects.” It cites existing state and federal requirements to treat surface water used for drinking water, as well as remediation efforts by the Klamath River Renewal Corporation for public water sources below the dams.

The letter also said it is unlikely that recreational activities on the river would cause adverse health effects, an assessment consistent with testing conducted by the North Coast Regional Water Quality Control Board this spring.

The rejection notice was published on the district’s website last Friday.

Ed Valenzuela, the only Siskiyou County supervisor to vote against the emergency request, said there is no strong data to support an emergency declaration.

“Is the river different than before? Yes. Is it the ‘river of death’ that some people talk about? No, it has not reached that level,” Valenzuela said.

He added that residents along the river have known for years that toxic algal blooms are occurring as water slowly accumulates behind the dams, and that wells in residential areas have not dried up in large numbers to warrant a state of emergency.

“This project took 10 years,” Valenzuela said. “It was a significant event, but they knew some of these things were going to happen. They knew that if they let some of the sediment through, the water quality would change.”

According to the OES letter, the county had not issued a public health alert and “there are no catastrophic situations or conditions of extreme danger to persons or property.”

State agencies, including the California Department of Fish and Wildlife, will continue to work with the county to monitor water quality.