Just a heads up ... I brewed today and the high was only 83ish outside. Water + many jugs of frozen OJ simply did not do the job - it took 30mins of recirculating at a dribble back into the kettle just to get to 72 degrees. And only then did I start to direct the flow into the fermenter.
Looks like you'll need straight ice to cool your wort down efficiently. Especially as the weather enters higher temperatures.
I've just been chilling it to 85-90 (or whatever the groundwater temp is that day) and sticking it in the fridge for a couple hours before coming back to the brewhouse and pitching.