Thread: What the Wier!

Am I reading it wrong? I thought it's saying the water was COLDER (by 1.3ºC) at the fishing access pier than between the skimming wier and the dam. That means the trout would be in COLDER water, no?

I thought the fishery BELOW the dam would be oxygen poor, negatively affecting the fish population moreso than the temps? I think the fish can withstand more temperature swings than just 1.3ºC, but lack of oxygen can have a much worse effect, likely on the whole ecosystem.

Or I'm reading it wrong.

Originally Posted by Joedog

Am I reading it wrong? I thought it's saying the water was COLDER (by 1.3ºC) at the fishing access pier than between the skimming wier and the dam. That means the trout would be in COLDER water, no?

I thought the fishery BELOW the dam would be oxygen poor, negatively affecting the fish population moreso than the temps? I think the fish can withstand more temperature swings than just 1.3ºC, but lack of oxygen can have a much worse effect, likely on the whole ecosystem.

Or I'm reading it wrong.

So the deep water with less DO is also much colder. The weir forces the warmer surface water with more DO to be discharged through the dam.
Table rock has no weir and the discharged water is around 50 degree. Seems like they have big concrete rip rap things the froth the water up before it reaches the hatcheries increasing DO.

Even with a Weir I would expect the discharge water to be cooler than the surface temp above the dam, which would account for the 1.3c.

I think