Phos Chek is not great for the environment, especially to aquatic life. So ideally there'd be some solution that doesn't use more of it.
agricultural level irrigation at the ready
The fires are exacerbated by California's long term drought, if there's large quanties of water laying around, then they probably wouldn't have such a bad fire season.
Inhabited locations in fire prone areas
I think there should be a re-evaluation of whether or not to let people build or rebuild in especially fire-prone areas.