I'm sorry I'm not sure. It will be on till park closed.
I'm not normally at the park earlier in the day. The absolute earliest, that I've been at the park, for me to arrive is around 2:30p, and I've not seen the sprinklers going. The absolute lasted time that I've left the park is probably between 8:30p-9p, and again I haven't seen the sprinklers on, so maybe they run then earlier in the morning or even late morning.
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