In preparation for my OC hike at Brady's Run Park, I sent an email to the BC recreation dept, and copied the sheriff, to give them a heads-up (the parks are patrolled by Sheriff's deputies, not local police). Later, I spoke on the phone with the park's facilities manager. She had already let her staff know, and she was very friendly and welcoming. Since she was so nonchalant about it, I asked her if she had dealt with the issue before, but she said no, that was the first time. So far, so good.
Then I got a call back from Sheriff George David. He also seemed very friendly and welcoming, and said he was a supporter of gun rights, an NRA member, gun collector, etc. That sounded great, but I always wonder if an elected official is sincere or just pandering when they're telling you something you want to hear. But then he really surprised me - he gave me his cell phone number and told me to call him if we had any problems during the hike! Sounds like he's sincerely OC-friendly.
Looks like we may have a place for a meet-and-greet and/or more hikes next year - Brady's Run Park and Brush Creek Park both have picnic shelters and hiking trails. Score.