December 18, 2023

Water Closure 

ISDA’s water closure along the Snake River has been amended as of December 18. Beginning December 18, water access is open to the public between Broken Bridge (Yingst Grade) and Pillar Falls. Water access from Pillar Falls to Twin Falls Dam remains closed (IDAPA 02.06.09.135).

Water access between Broken Bridge (Yingst Grade) and Pillar Falls is accessible only during Centennial Park operating hours. Current operating hours at Centennial Park are 8a.m. to 6p.m., weather dependent.

Decontamination

Decontamination for watercraft entering and exiting the river between Broken Bridge (Yingst Grade) and Pillar Falls is mandatory. Any watercraft or conveyance is required to be decontaminated prior to launch and upon exit of the river. The decontamination station is operating at Centennial Park.

Watercraft includes but is not limited to boats, kayaks, paddleboards and other devices used in water. Conveyances including duck decoys, waders, fishing tackle, life jackets, and anything that has touched the water must also be decontaminated. ISDA watercraft inspections and decontaminations are free to the public.

Mandatory decontamination applies to all watercraft launches anywhere between Broken Bridge (Yingst Grade) and Pillar Falls. Watercraft launched at any access points between Broken Bridge (Yingst Grade) and Pillar Falls (i.e. Auger Falls Park, Yingst Grade shoreline access, etc.) must be decontaminated at Centennial Park prior to launch and upon exit of the river.

Access to the river between Broken Bridge (Yingst Grade) and Pillar Falls is prohibited outside of Centennial Park operating hours. Access to Snake River from Pillar Falls upstream to Twin Falls Dam remains closed.

See the decontamination and closure map here.

Monitoring the Impacted Area

Copper levels in the Snake River have dissipated as anticipated and ISDA is not detecting any additional copper in the river system. The adult mussel that was identified in the river pre-treatment experienced mortality within 48 hours of the first treatment block. Although initial veliger sample results indicated the treatment impacted larvae and adult populations, it is premature to conclude complete eradication at this stage. Quagga mussels generally stop reproducing once the water is below 14 degrees Celsius. Sampling will begin again in the spring once water temperatures reach 14 degrees Celsius. Surveying will be an ongoing effort to determine the success of the treatment.

Outside the Impacted Area

We urge all Idaho watercraft owners to CLEAN DRAIN DRY. Please reach out to ISDA at any time for a free decontamination wash. 1-877-336-8676

Media Contact:

Sydney Kennedy

Public Information Officer

(208) 332-8507

media@isda.idaho.gov

General Questions:

(208) 332-8620

info@isda.idaho.gov