Logging roads that are not properly designed or maintained can also create erosion problems. Fire Uncontrolled fires can destroy entire forests, leading to massive erosion and water pollution. But uncontrolled, high-temperature fires, which burn entire trees and leave hillsides free of all vegetation, can damage soil quality and leave watersheds vulnerable to tremendous damage. Grazing Grazing practices, particularly in dryer areas, can impact watershed quality. In dry areas, cattle trample stream banks, destroying riparian vegetation and habitat, and causing erosion and the loss of native plants.
Mining Abandoned mines are a major source of river pollution throughout the west.
Abandoned mine shafts leach heavy metals such as copper, mercury, zinc and lead into the water supply. There are thousands of abandoned mines in California, dating back to the times of the Gold Rush. Many of these mines are located within National Forests. At present, there are few effective ways to clean up abandoned mines or mitigate their negative impacts.