I use a submersible “fountain pump” from the hardware store garden section to recirculate water from a bath. I still have to dump it out and refresh several times which I use to water the lawn, but the water use is less than when I did straight through. Once I get down to 100-110 I empty out my water bucket, put just enough water to cover the pump, and start dumping ice in. The recirculating ice water can cool down to 60 no problem.
The key to efficient water use is that you want your discharge water to be as hot as possible. This is why counterflow chillers are so much more efficient: the intake is always near boiling, so the waste water is always hot. With immersion chillers as you cool the wort, the maximum waste water temperature drops, so it becomes less efficient.
A whirlpool system will improve the efficiency of the immersion chiller as well as improving the cooling rate. When I get a pump for hot wort I will probably switch to doing the starting phase with straight-through water. There is no point in circulating if the chiller output is as hot as possible.