To have a party in one of the pavilions do you have to reserve it or is it first come first serve?

Reserve it at the office behind the park

Yes, the reservation fee is only $45.

Reservations are given first priority. There are some picnic tables not under the pavilions that are first come first serve but if you want a pavilion, you definitely want to go in to reserve one.

I would reserve one. That way you get one.

Reserve

Either best to contact park and rec dept 2 reserve

No I dont think so. I see some pic nic type people at the pavilions all these time.