Are there showers here

Yes. Campground loops. As long as you pay the park entrance fee you can use any shower in the entire park. D loop is the newest camp loop and has the nicest showers 🚿

There showers in the campground... But that's the only place I know of that there are showers. They run on quarters or at least they used to.

The showers at the swim beach takes quarters and there is a change machine on the east side of the building facing the reservoir.

There are also showers at the swim beach but you have to pay $1