Douglas County PUD unveils railroad bridge PIT tag project

PATEROS – The Douglas County PUD is proposing a project to install passive integrated transponder (PIT) tag-detention antennas on the utility's railroad bridge, which crosses the Methow River at the confluence of the Methow and Columbia rivers.

The PIT tags, attached to the bridge pilings, will monitor fish entering and exiting the river.

Pateros City Administrator Jord Wilson told the Dec. 16 meeting of the city council that he met with Tom Kahler, the PUD’s senior fisheries scientist, to discuss the planned project.

The railroad bridge is the ideal spot to locate the tag array because the Methow’s width is at its narrowest at the bridge, and all fish entering and leaving the river must pass under the bridge. The tags can monitor the entire river depth at any water discharge, and the design of the bridge piers provides recesses where the antennas can be placed to protect them from debris.

The bridge is supported by three concrete piers where six antenna assemblies can be secured in the 14-foot recesses on each side and positioned to be flush with the concrete face.

The antennas will be assembled at the Boise, Idaho, Biomark facility and transported to the job site.

These are not small units one would associate with fish monitoring devices. The assemblies vary in length from approximately 13 feet to 32 feet. The longer unit will weigh about 2,300 pounds before being submerged, where the weight will be about 1,525 pounds. Once installed with air or foam floats, the assemblies can be rendered neutrally buoyant.

Earlier this year, the Washington Department of Fish and Wildlife (WDFW) approached the council about anchoring a large barge equipped with PIT tags. WDFW wanted to place it near the takeout spot on SR153 along the west shore of the Methow River upstream from the mouth. Since the barge is an over-water structure and would anchor in a PUD reservoir, WDFW needed PUD approval to deploy the barge and council approval to use the city launch facilities. 

The PUD objected to the placement for stream silt management, boater safety, and liability reasons. Last April, the city council denied the WDFW barge, citing unresolved PUD permitting issues.

Mike Maltais: 360-333-8483 or michael@ward.media