Originally published Wednesday, April 16, 2014 at 2:38 PM

Salmon swim past Wanapum Dam
Modifications to the fish ladders at Wanapum Dam are allowing safe passage to upstream migrating adult salmon and steelhead.

BEVERLY, Wash. —
Modifications to the fish ladders at Wanapum Dam are allowing safe passage to upstream migrating adult salmon and steelhead.

A crack that was found February in Wanapum Dam resulted in a reservoir drawdown at the dam that had left the original fish ladders high and dry. But the fish ladders have been modified to allow passage.

The Grant County Public Utility District said Wednesday the most recent counts showed 31 spring chinook and 102 steelhead successfully exited the Wanapum Dam left bank fish ladder this week. They were the first of 15,000 spring chinook expected to make their way up the Columbia River to spawning grounds.

Three steelhead and eight whitefish have gone on to pass the Rock Island Dam fish ladders since counts began this week.

I just heard that from a bone dry fish ladder to watering it up, in an hour and forty minutes the first chinook passed through the modified fish ladder. A large pump puts water in the fish ladder, and at the crest the fish jump over a false weir as though moving up to the next step pool in the ladder, only instead they land in a water slide that takes them down to the lowered forebay on the upstream side of Wanapum Dam. So far, so good. The second ladder should come into service today, well before large numbers of fish begin showing up.

The weir/slide will be a fun thing to watch when the fish really get moving thru...I wonder kind of capacity it will have?

Fish on...

Todd

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Sounds like a hour and forty minutes of swimming in line before it your turn on the slide...wild waves on a sunny weekend...

I wonder what their plans are for the fish/smolts when they head down river

That is going to be crazy when the Sockeye start coming over. I hope someone up there has a video camera.

Capacity shouldn't be a concern until it gets above 12 fish per minute, or possibly higher. So far, so good. The fish counter and a camera are stationed at the water slide because the usual fish counting window in one of the ladder pools is partially dewatered.

When the sockeye start coming like gangbusters, I think it will go to a combination of the two modified fish ladders plus trap and haul from Priest Rapids Dam fish ladder. Everyone is aware it's going to be a busy season, and that's why they've been working non-stop since the draw down began.

Smolt passage will be through designated spill gates. The fairly new fish bypass is literally high and dry and out of service for this season.

If they can't get 'em past WD efficiently, it could make the fish in' a bit better…

Been googling for a vid of the retrofit in action the past week… so far, nun yet.