Proposed fire management strategies and potential hydrologic effects in the Sierra Nevada

After several decades of remarkably thorough fire suppression, the mixed co nifer forests of the Sierra Nevada are unnaturally dense and in a state of high susceptibility to stand-replacing fire. These large, high-intensity fi res can greatly increase the delivery of water, sediment, and nutrients to streams and severely impact aquatic life. A variety of strategies to deaf w ith the fire risk have been proposed in recent years. All the proposals hav e mixtures of possible consequences to the aquatic system. Most of the dens e forest areas are probably producing less water and sediment than before t he Gold Rush of 150 years ago. Various types and intensities of prescribed fire and mechanical removal will tend to increase streamflow and sediment d elivery. Those effects must be weighed against the risk of more severe cons equences of intense, widespread fires. The full range of issues involving v egetation management, fire risk, and related aquatic effects continues to b e actively debated in the Sierra Nevada.