Our damaged headwaters

From the Public Policy Institute of California:

"We’re seeing intensifying wildfires in California, especially in the headwater regions where our rivers originate. More intense fires have significantly changed the composition and structure of forest ecosystems, affecting both water quality and quantity, though not always for the worse. For example, large fires can significantly reduce the amount of vegetation covering the land, which reduces the amount of water consumed by plants. Burned areas also have much less water circulating in the soil. 

Both of these post-fire processes have a positive impact on streamflow, as more water works its way into the water table and streams. But the loss of groundcover plants from intense fires also increases surface erosion, which can cause landslides in the rainy season. Ashes and sediments flowing into streams harm water quality..."