Pools Closed - Where to Swim?

I'm gearing up for the Lake Geneva Half on 9/12.  The facility here in Mayville at which i'm a member has their pool closed until after Labor Day.  The next closest pool is in Hartford - also closed until after Labor Day (why couldn't they stagger it??)  The other two closest pools are at the Beaver Dam and West Bend Y's - but they're ten bucks a day for nonmembers, and there's no way i'm shelling out $20 or $30 a week for two weeks.

There IS a hotel pool in Iron Ridge that lets the public in for $4 - i stopped by yesterday during a training ride to check it out, and it's an oval probably 12 yards long.  I wanted my fix, and since i was right there without any better ideas i actually swam laps and circles in it for the better part of an hour before hopping back on the bike.

While I am 100% confident in my strength and ability on the swim, I would like to at least maintain for the next couple weeks before LG (plus i LIKE to swim!)  Anyone have any idea where a pool within a reasonable driving distance of Mayville might be that i could haunt for a couple weeks?  Mayville is just about smack dab between Madison and Milwaukee on the east-west plane, and also about smack dab between Oconomowoc and Fond du Lac on the north-south plane.  If I can get a swim buddy (or at least talk my wife into watching me) I will be working in a couple OWS, but OW doesn't quite jive with my schedule on weekdays.