What's not really mentioned here is that these sorts of encampments are usually build along CA freeways because those are policed only by the state (Caltrans / CHiPs) rather than the locality (city/county). Even when there is an obvious hazard (garbage buildup and drift into the road, visible fires burning, throwing objects at cars, walking/crossing the highway or on/off ramp) nothing is done. Typically, it takes a call to your CA state senator to get any action (caltrans doesn't respond to messages within a month).