Here more about Louisville Metro Parks in this fabuLOUs podcast!
If you don't have access to a pool, there are many FREE options to cool down and get wet during the hot months in Louisville. Many of the metro parks have spray areas and splash pads for lots of fun on really hot summer days. They are free and inside of a metro park, so they are surrounded by all of the other amenities at that park like playgrounds and picnic areas.
Here's a list of the free ones!
Mary T. Meagher has an outdoor sprayground. Here is our review.
For a fee:
The Louisville Zoo also has a nice splash and sprayarea, Calistoga Splash Park. Admission is required!