During hot summer time it's on all the time
Sunday July 21, fountain was turned off at 7:30pm no public information on operating hours I can find. UPDATE: Called parks and rec fountain runs daily until 7pm synced to government time so you know when ever, maybe.
Weekends when the weather is good for sure
Usually on the weekends or early afternoon when its good and warm out. Go ask the security office in the glass building to be sure
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