Generally, events with less than 100 people don't need permits but sites are first come first serve.
No, the Portland Police will not come raid your bday party and arrest your kids. However, Portland Parks & Rec might like you to get a permit or something if the gathering is large, but you'll have to call them. Protip, just tell google to call "portland parks and recreation" and it will call them for you.
You can reserve one of the two areas or take your chances -- but if you reserve you will have the space for sure.
I have seen people just show up for a party, decorations and all with no permit. About 10-15 people. I'm sure if you are taking just a couple of tables it is fine. Anymore than that you should probably call Portland Parks. Basically i are with everyone else. Lol.
Basis Brandon tells it how it is. If its 10 people or less just go for it. Bigger groups check with the parks people.
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