Papago Park was once a State Park, and that was when they dug the ponds and used them as holding ponds for bass. The hatchery was between a couple ponds but is now only a concrete base. The ponds are still holding bass even though they had originally shipped bass from Papago Park to waterways throughout the state.
Eventually, it became cheaper to purchase from commercial fisheries to stock Arizona waters (including Papago, but Papago doesn't get stocked with bass).
Bunch of fingerlings here - attempting to survive long enough to become 'blue-ribbon bass.'
Here are some bigger ones.
Nothing huge in these pictures, but there are some decent ones out there. And if you do the catch & release, it doesn't really matter how big they are but rather how well they are biting.