Activities such as road building, logging, mining, grazing, hydrologic modification or excessive recreational use can degrade the integrity of watersheds. Watersheds may be impaired and require restoration to meet clean water goals. Soil erosion and nutrient runoff in riparian zones are effects of impaired watersheds.
Studies have linked extensive flood damage to clearcutting of timber (particularly on steep slopes) and to the networks of logging roads punched into forested regions. Damage is widespread and highly variable from watershed to watershed and is not limited to the human infrastructure. Many rivers and stream channels have receive extensive deposits of both organic debris and fresh sediment. Some streams are impacted more than others. Some organic debris may be beneficial in the long run, but the heavy sediment deposition in some rivers and streams is likely to affect channel morphology and aquatic habitat for decades.