That's really sad. Having spent my childhood years in the San Jose/ Santa Clara area, we used go to the beautiful parks and beaches there often. I have very fond memories of the area and I think it's terrible that others may not be able to enjoy them. But I have no answers either.
As for finding volunteers, it may be possible. The Oregon States Parks Dept. has a program that lets people camp out in a park for the season. The volunteers are responsible for basic things like cleaning toilets, picking-up rubbish, reminding park users about the park regulations, etc. They can call in the park rangers or police if there are more serious issues. It's popular with retirees and people who for whatever reason do not work that time of year.
CC - They post signs and ticket violators, but it's impossible to keep people away entirely.
Everything in moderation, including moderation.
2007 Rodriguez Adventure/B72
2009 Masi Soulville Mixte/B18
1997 Trek 820 Step-thru Xtracycle/B17