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Economic and dam related articles

Laser Protects Young Salmon
from Birds

by Staff
My Columbia Basin, November 19, 2019

McNary Dam, seen here from the Washington side of the Columbia River, is a critical passage point for migrating salmon and one that river managers have been trying to improve for years. (Bruce Ely/The Oregonian) UMATILLA, Oregon -- Like a scene out of a science fiction movie, a bright green laser penetrates the darkness at McNary Dam on a mission to deter birds from snatching juvenile salmon. The U.S. Army Corps of Engineers installed the laser which has a range of 950 feet to a mile depending on the weather.

The laser is programmed to move in a random pattern on the juvenile outfall pipe where juvenile salmon are returned to the Columbia River just downstream of the dam.

"Birds see the dot produced by that color of laser as a solid object moving towards them and fly out of the way because they think they are being chased or about to be hit by something," Mechanical Engineer Caleb Willard said.

The area the laser is focused on is in a boat restricted zone, so there is no danger of anyone looking at the beam, which is strong enough to damage eyesight if looked at directly.

Several innovative solutions were considered after a sprinkler that originally kept birds clear of the outfall pipe was wiped out by high water. The laser was selected, but more help was needed. While the first laser had some success while operating in the spring and summer, it was operating at the edge of its effective range. So, a second laser was purchased in September and will be mounted on the outfall pipe itself next spring.

In April, the effectiveness of the newest laser at McNary will be tested. If it proves itself to be good at keeping birds away from the young salmon, more may be installed at other dams along the Columbia and Snake Rivers. Ice Harbor Dam has already expressed interest.

Related Pages:
New laser at McNary Dam is the latest technology for deterring birds by Hannah Mitchell, US Army Corps of Engineers, 11/15/19

Laser Protects Young Salmon from Birds
My Columbia Basin, November 19, 2019

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