Best management practices for riparian areas
Forest streams, lakes, and other water bodies create unique conditions along their margins that control and influence transfers of energy, nutrients, and sediments between aquatic and terrestrial systems. These riparian areas are among the most critical features of the landscape because they contain a rich diversity of plants and animals and help to maintain water quality and terrestrial and aquatic habitats. These fragile areas are easily disturbed, and caution is needed whenever forest management occurs within them. Riparian areas are often linear features of variable width that have high edge-to-area ratios but generally occupy only a small part of the landscape. However, the linear nature of riparian areas means that resource managers and loggers, either through active management or the need to gain access to a site, will invariably come into contact with these features. Therefore, the proper management tools are needed to maintain the functions of riparian areas and minimize disturbance to the terrestrial and aquatic systems.
Best Management Practices (BMP’s) are developed to prevent or minimize the adverse impacts of forestry activities on water quality while permitting the intended forest management activities to occur. They serve as the cornerstone for most State water quality protection programs. Possibly the earliest effort to establish BMP guidelines was the "Criteria for Managing the National Forests in the Appalachians" (1971) by Regions 8 and 9 [Southern Region and Eastern Region, respectively] of the USDA Forest Service. The development of BMP programs has been a collaborative effort among State agencies and organizations (both public and private) and Federal agencies to identify practices that reflect the particular physiographic, economic, technical, and political considerations of each State. Monitoring has shown nationally that compliance with BMP’s is relatively high. However, by definition, BMP’s were designed to protect water quality, not the other functions and values of riparian areas. We need to move beyond BMP’s based solely on water quality to address these additional functions and values.
All State BMP programs recognize the importance of retaining some form of riparian management zone (RMZ) with management options that minimize impacts to the water resource. Achieving BMP compliance in these areas generally requires greater care, reduced physical intrusion (e.g., skid trails, roads, equipment) into the riparian management zone, and often reduced levels of harvest (e.g., thinning, uneven-aged management) or no harvest at all. It also requires preharvest planning that considers the landowner's management objectives. The BMP’s discussed in this chapter pertain to lands where silvicultural or other forest management activities are planned and conducted. This chapter will describe the management issues of concern, water bodies that are addressed by traditional BMP’s, RMZ options, and approaches to the development of RMZ guidelines that move beyond BMP’s and address issues other than the protection of water quality.