James Thebaut is a Los Angeles ecological documentarian and long-time environmental activist. He argues in his latest documentary, “On The Brink: California’s Watershed,” now airing on PBS, that the intensity of California’s wildfires is due as much to bad policy as it is to climate change. He talks about the state of California’s forest system and how both water scarcity and forest clearing practices are impacting the watershed and the ability of forests to absorb water or resist fires.