The Science Behind Stream Corridor Protection The benefits of protecting stream corridors are well documented. In a nutshell, stream corridors protect the water quality of streams. The majority of sediment and pollutants entering local streams occur during storms. With a vegetated buffer of 100' outside the 100-year floodplain provides protection and nutrient removal during such high flow events. Vegetation along stream corridors traps and stores those nutrients that degrade water quality. An overabundance of nutrients, such as phosphorus or nitrates, act as a fertilizer causing aquatic plants to undergo rapid population growth called an "algae bloom." When the algae die and sink to the bottom of the stream, oxygen is consumed during their decomposition by naturally occurring bacteria. Aquatic life needs oxygen to survive and can be severely stressed, fail to reproduce, or die if oxygen levels are low for a long period of time. The roots of plants in a stream corridor also hold onto the soil, preventing erosion. Vegetation along the stream also traps sediment washed towards local water bodies during storms. Sediment in a stream can reduce the transmittance of light and turn a stream the color of the surrounding soil. The damage to the stream is not merely aesthetic. Streams laden with sediment are inhospitable for fish because the sediment becomes trapped in their gills and impedes uptake of oxygen. According to the 2000 New Jersey State Water Quality Inventory, approximately 65% of New Jersey Department of Environmental Protection's macroinvertebrate monitoring sites are moderately impaired. Suspected causes of this water quality impairment include: Stormwater runoff from land uses such as agriculture and urban and suburban development containing sediment, nutrients, pesticides and other toxic substances. Inadequate stream flow (water consumption, inter-basin transfer of water and wastewater, drought and flooding). Habitat destruction, including erosion. Trees and vegetation within a stream corridor aid in keeping water temperatures low. Studies show that streams with no shading vegetation have higher water temperatures, which may be linked to levels of oxygen solubility so low that fish cannot survive.1 Decaying trees become debris in stream, providing essential habitat for many fish, especially salmonids (salmon, trout, and related fish). As floating debris, their bark acts like a sponge to soak up pollutants. Stream corridors provide contiguous migrating corridors that can maintain the biotic diversity of native plant and animal populations. This is important especially in urban areas where streams and associated forests are often the only suitable habitat areas remaining after urbanization. Vegetation within these corridors also provides dissolved and particulate organic food needed to maintain high biological productivity and diversity in the adjoining stream.2 A large percentage of New Jersey's endangered species rely on stream corridors and associated wetlands for survival. 1 Seth Wenger, A Review of the Scientific Literature on Riparian Buffer Width, Extent and Vegetation (1999). 2 United States Department of Agriculture, "Riparian Forest Buffers: Function and Design for Protection and Enhancement of Water Resources (1991).