Water Intake Trash Screens

We began a tour of the Lockport Powerhouse by going up the stairs on the side of the powerhouse to the upstream side. 

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When I got to the top of the stairs, I noticed the following:

And the view off to the right was:

Walking around this gizmo to see what was on the other side, I saw water intake gratings and more of that "vertical thing". The purpose of the gratings is to prevent trash from flowing through the turbines.

These input screens are for the two generators that are still operational in the powerhouse.

Later, I remembered to ask what that "conveyer belt thing" was all about. It is for cleaning out the trash that accumulates against the intake screen. They place a dumpster at the end of the conveyer belt that you see in the third photo. Then the vertical arm is extended so that the scraper at the end reaches down below the trash. And then the arm is retracted to pull the trash up and over the top of the screen so that it falls onto the belt. The arm is on rails so that it can work its way across the face of the screens.

A view of the conveyer belt from the screen side. You can see the roof of the powerhouse in the background.

As another example of water intake screens, this is the gate room of the Keokuk Powerhouse.

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On the right side just beyond the metal hand rails are the tops of the intake screens. They extend 40 feet down.

In this closeup of one end of the intake chamber, it looks like all but one of the screens has been replaced.

Used with permission from Jim Rabchuk

Four of the intake screens feed water to the scroll chamber for one turbine.