Invasive mussel species detected in Idaho river

The Idaho Department of Agriculture is asking the public to stay out of the water in the Centennial Waterfront Park area in Twin Falls as it has confirmed the presence of quagga mussel larvae in the Snake River.

In a press release issued Tuesday, the department said multiple samples of quagga mussel at larval life stages were found in the area by the agriculture department’s early detection monitoring program.

“These invasive pests will clog pipes that deliver water for drinking, energy, agriculture and recreation,” Idaho Gov. Brad Little said at a press conference Tuesday. “This is a very high priority for Idaho and for me, given the gravity of the risk. If we are not successful, an unchecked spread – which we are doing all we can to stop – has the potential to cost Idaho hundreds of millions of actual and indirect costs.”

Little said he is thankful the agriculture department caught the mussels early on and has already implemented a “robust response” to remove the invasive species.

According to the press release, this is the first time a rapid response plan has been put into action for quagga mussels in Idaho. The department is implementing a rapid response plan that includes notifying impacted entities, implementing containment measures, conducting delimiting surveys and evaluating for potential treatment options.

The department is asking for the public’s cooperation to stay out of the water at Centennial Waterfront Park as staff works to contain the mussel population. Boat ramps and public access to the water are closed temporarily.

“Our Invasive Species Program is prepared to respond to these findings quickly in an effort to contain mussel population growth in such a vulnerable area,” agriculture department director Chanel Tewalt said in the press release. “We greatly appreciate the public’s cooperation and plan on opening the area as soon as possible to minimize the impact to businesses that rely on the Snake River.”

All watercraft users are encouraged to follow the “Clean, Drain and Dry” actions for watercraft and equipment before entering and after leaving Idaho water bodies. The agriculture department watercraft inspection stations are also operating across the state and mandatory for watercraft users to stop at.

Lt. Governor Scott Bedke said he was disappointed to learn that this invasive species has infiltrated the Snake River.

"This is a major issue for not just the surrounding area but the entire state. If left unchecked, this can negatively affect our water quality, majorly impact the Snake River’s ecosystem, clog our irrigation pipes, and take over our ship and boat hulls," Bedke said in a press release.

The lieutenant governor applauded the Department of Agriculture’s early detection and quick response to this issue.

"[I have] faith in their action plan to contain – and potentially treat or remove – these mussels. I urge everyone to adhere to the Department of Agriculture’s rapid response plan so we can get this serious situation under control.”

The presence of the quagga mussel larvae is concerning, Molly McCahon, Lakes Commission executive director, said.

"This means they are not fully established adult mussels and there remains the possibility they won't survive," McCahon said. "It also makes containment is very difficult. If they do become established; however, the Pacific Northwest would unfortunately lose the ability to claim that the Columbia River Basin is free of invasive quagga/zebra mussels."

The three largest tributaries to the Columbia River flow through Idaho — the Kootenai River, Pend Oreille River, and the Snake River.

"This discovery in the Snake River is highly concerning and we appreciate the work ISDA and neighboring local, state, and federal partners have ahead of them," she added.