you might find it easier, to get a PTO generator, and then buy some regular pond / pool water pumps (depends on how much length pipe/hose and inside diameter of the pipe/hose, and how high you will need to pump water up to) more head loss / pressure loss the bigger pump you will need.
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on a side note, you might try contacting local fire departments in and around your area. they might have a pump you could use.
you might also try contacting a local machinery rental place. look up "machinery rental" in the old paper phone book. and call around a couple hours away.
30 to 40 acres is a lot of water to flood.
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with you living fairly close to Chicago and great lakes. i think there are 2 dredging companies in and around Chicago area. that might be able to offer a large size pump
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if creak was the highest point and the area you are wanting to flood, was lower than creak. the cheapest and easiest route to flood would be to setup a "siphon" using 4" or larger size pipes.
have had to setup a few siphons on a couple lakes here, when overflows got clogged up. and bought cheapest smallest sump pump i could find, then 12V to 110V cigarette convertor for a vehicle. i used it to prime the 4" pipe. used a 3 valves. so i could prime the pipe up with water. and able to drain 1.5 to 2 acres of lake down 5 feet within a day or 2.
someone a while back, created a kinda like a old snow sled ((rails on bottom)) and used a long pole to push sump pump out into the water. vs trying to toss sump pump out into the water. so they could prime a siphon, or was it to water some grass
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1 acre = 43,560 square feet.
43,560 * 1 feet depth = 43,650 cubic feet
43,650 * 7.48 = 325,828.8 gallons
30 acres = 9,774,864 gallons of water
you will be looking at pump or pumps that could pump in the 10's of thousands of GPH (gallons per hour) anything less would be painfully slow.
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you might look into buying some regular "water pumps" powered by gas engine. and setting up a larger size or secondary larger fuel tank. and then just mounting them on a pallet. so you could move them around with a set of pallet forks on back of tractor or on pallet forks on the FEL.
that way you could just set the gas powered water pump were wanted. and then just go around twice a day, filling them up with gas. and letting the pumps run all day and night long. for how ever long it takes. i am gong to assume what ever you get it will take a few weeks perhaps a couple months counting down time of not wanting to get out there and pump water.