If that's the worse thing you can say then I think we be fine people who smoke weed are very friendly. Don't be a douchebag.
No one should feel unsafe in a park especially with kids. One thing that helps me is greeting people even if you think they are doing something inappropriate. They will either respond with a friendly greeting or not. It's rare that folks aren't friendly. Even the young adults are surprisingly respectful. I am in the park Mondays at 10am and Tuesdays at 4:30 @ the community garden, so you don't have to be there alone.
I believe you would have to contact the Parks & Recreation Division of the city government. If you see inappropriate behavior like that in public, call the Police. They're here to protect us.
That will be an awedome idea also when I used to go running in the mornings or evenings there would be guys peeing or mas.... Inside the trees it was scary when I would go alone or with my little kids, I stopped going.
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