Same thing I was thinking, but on a larger scale since the intakes are so huge. Screens close to the intake would probably restrict flow too much, so you need a containment area for “de-minnowed” water. Something like a large reservoir/basin that keeps the minnow or any other wildlife from getting anywhere near the intakes constructed around the intakes to provide enough volume for them while protecting the precious little minnow.
Depending on the volumetric flow rate(s), there is a calculated basin-like dimension for a hold-up volume.
To dig and lay a concrete basin is much more involved, time consuming and expensive. However, with the stainless screen I mentioned in my post, the water velocity will be low enough not to cause a high delta P, affecting the water flow rate, hence; any vibrations affecting the screen or causing pump(s) cavitation and damaging the impeller(s).
The existing pumps must have existing screens (filter cages) around the intakes. They should be left alone and one large fence, if you will, erected per the description in my previous post.
The cost of such a construction is next to zero compared to the cost of the pumping station.
As an aside, the zero needs to be caged, but that's for a different reason altogether.
“Same thing I was thinking, but on a larger scale since the intakes are so huge. Screens close to the intake would probably restrict flow too much, so you need a containment area for “de-minnowed” water. Something like a large reservoir/basin that keeps the minnow or any other wildlife from getting anywhere near the intakes constructed around the intakes to provide enough volume for them while protecting the precious little minnow.”
there is already exactly such a project under consideration(the Two Gates project, total cost , about 20 million and it’s “shovel ready”, too). Unfortunately, they don’t WANT the water pumped, fish or no fish. The fish is just the lever species they are using to get the water shut off. If you save this NOT endangered fish, which is genetically the same as smelt that exist all over the country, they will find some other species to claim as endangered, in order to get the water shut off.
There are 2 REAL problems that exist in this whole thing. 1 is a twacked-out communist public serpent member of congress by the name of George Miller, who represents the Contra crackhead.. err Costa area of the Bay. He believes that the farming and use of water in the SJ Valley are illegal (and probably immoral, too) and is in general an oxygen thief to begin with. The other problem is that the cities along the Sacramento River and Delta areas have been using the water to dump their partially-treated sewage overflow for many years. They don’t want to have to pay to upgrade their inadequate wastewater treatment facilities to meet current standard. The above folks are blaming the farming and the pumps, in order to cover up that their own area has been killing more of the fish (which are food for the Striped Bass and salmon, and so on) then the pumps ever have, by more or less poisoning them. So sayeth a report by the Army Corps of Engineers a couple years ago, anyway. Note that the above-named public serpent has a lot of refineries and chemical plants (which are not bad things in and of themselves) in his area, and would rather they get to release wastes only partially treated, into the Delta he professes to love because he hunted and fished in as a kid, than have some of the water pumped out to feed the world. That same water is there diluting the wastes down so they can have slightly lower sewage bills.
Note that this is only the beginning of the Valley’s problems, as the Eastside farmers are going to start having their water taken away either next year or the year after. Currently, it’s the Westside farmers that are getting clobbered. The rest is coming.
So something like two step screening? Question, even if the screens filtered just 30% of the smelt out wouldn't’t that keep them from being extinct?
I do not see any reason why this would not work. Does anyone else? I would like to see the minnows protected as well as other fish. This seems to me to be a solution that could work for everyone. Has it been considered and if not how do we get it to the people who can do it?