Sharraxaadda

What are the rules for a public park being used repeatedly for parties? More weekends than not my husband and I walk with our grandkids around Fellsmere Park and at the upper side where the picnic tables are people are using this area as their personal party spot. It isn’t fair that all the parking is taken and also all the public tables are being used. Is this allowed? I would think this would require a permit Can the city address this? This area is for everyone not for repeated family functions Trash left behind is also not fair to the other people who enjoy the park. I remember signs that were put up by the DCR but they aren’t up anymore.