What is a Stream Corridor? Why is it Important to Protect? In a society dependent on water for drinking, agriculture and industrial processes, streams provide the lifeblood for our well-being. It was once thought that water could be best controlled by channelizing it and distributing it after sending it to a treatment plant. According to Dave Rosgen, author of Applied River Morphology, when the works of man run contrary to the natural, stable tendencies of the river, the river eventually dominates.1 The best way to stabilize a stream and protect water quality is to preserve the stream's surrounding ecosystem. A stream corridor is composed of several essential elements including the stream channel itself, associated wetlands, flood plains and forests (see Figure 1 below). Maintaining the natural system of streams has many benefits for a community, the surrounding communities, and the regional watershed. If stream corridors are maintained in their natural condition, with minimum disturbance, they are instrumental in performing many functions, including: Adding to the natural character and beauty of the community Removing sediment, nutrients, and pollutants by providing opportunities for filtration, absorption and decomposition by slowing stormwater velocity, which aids in allowing stormwater to be absorbed in the soil and taken up by vegetation Reducing stream bank erosion Displacing potential sources of non-point source pollution from the water's edge Providing shade (with the plant life on its banks) that maintains cooler air and water temperatures in the area Maintaining biodiversity of aquatic plants and wildlife (learn more about biodiversity here) Preventing flood-related damage and associated costs to surrounding communities Helping to maintain adequate flows of filtered water to underground aquifers Providing greenway corridors for wildlife (learn more about greenways here) Streams flow from one municipality to the next, carrying sediment and pollutants in their course. Thus, protection of our watersheds must be a concerted effort among all our municipalities. Everyone pays the price for pollution and flooding in our streams - the high cost of treating and purifying water for drinking; the lack of recreational opportunities (fishing, swimming and canoeing); and the staggering cost of flood damage. Enacting a stream corridor protection ordinance in your municipality is a proactive and positive step toward improving water quality and helping make a difference regionally. Impacts on stream corridors, especially on surface water quality, due to urbanization and unplanned development are becoming quite visible in New Jersey. For example, several studies have shown that the deterioration of water quality in the Upper Millstone River watershed in central New Jersey is related to the increase in population and land development. According to water quality data, Millstone River and Stony Brook, except for their upper reaches, have fecal coliform concentrations and nutrient levels (primarily phosphates), which are above state recommended levels. In addition, the central segment of Millstone River is considered to be impaired with toxic metals and central and lower portions of the river and Stony Brook at Princeton show the existence of a degraded biota. Many of these water quality problems are caused by nonpoint source pollution. Nonpoint source (NPS) pollution, unlike pollution from industrial and sewage treatment plants, comes from many diffuse sources. NPS pollution is caused by rainfall or snowmelt moving over and through the ground. As the runoff moves, it picks up and carries away natural and human-made pollutants, finally depositing them into lakes, rivers, wetlands, coastal waters, and even our underground sources of drinking water. These pollutants include: Excess fertilizers, herbicides, and insecticides from agricultural lands and residential areas; Oil, grease, and toxic chemicals from urban runoff, automobiles, and energy production; Sediment from improperly managed construction sites, crop and forest lands, and eroding streambanks; Bacteria and nutrients from livestock, pet wastes, and faulty septic systems; Following are some specific examples of water quality degradation in New Jersey: Lake Carnegie in Princeton is undergoing an accelerated rate of eutrophication with extensive problems of algal blooms and low dissolved oxygen levels during summer. A study done by Rutgers University in 1977 revealed that, 100,000 lbs of phosphorous (primarily from Upper Millstone and Stony Brook subwatersheds) are transported into Lake Carnegie annually. Stormwater runoff contributes roughly 52% of this load and the remainder is from the base flow and point sources. Soil erosion by stormwater is the largest process carrying pollutants to our waterways. An average acre of land under cultivation looses about 5 tons of topsoil per year due to erosion. These eroded sediments and associated organic and nutrient pollutants enter our streams. Sediments, nutrients and pesticides running into waterways from area croplands are believed to be the cause of chronic fish kills that have occurred in East Windsor area. Duck Pond Run in West Windsor Township has consistently recorded high levels of bacteria. The assumed cause is the input of nutrients from fertilized lawns and a golf course in the vicinity. The original capacity of Curlis Lake in Hopewell Township would be reduced by 40% by the year 2004 if no action is taken to control the excessive sediment input to the lake. Mill Pond in West Windsor Township and Mountain Lakes in Princeton Township are experiencing sedimentation and algae problems as well. Between 1987 and 1990, an oil leak occurred within the Jasna-Polana Estate, off of Route 206 in Princeton Township, which affected portions of Stony Brook. Although efforts were made to clean the spill, oil retained by the soil is still suspected of contaminating the stream. Adequate protection of stream corridors will eliminate some of these water quality problems by removing sediments, organic matter, and other pollutants from runoff and waste water before entering stream, and displacing potential non-point source pollution, such as underground oil storage tanks from the stream corridor. Establishment of proper maintenance standards for stream corridors is critical. The effectiveness of stream corridors in buffering the streams to maintain water quality and performing other functions depends on the defined width for the stream corridor (the area encompassing the critical environmental components and a buffer) as well as the permitted uses within the corridor. Although a buffer strip is defined as an undisturbed naturally vegetated zone, the term "undisturbed" should not be taken in its most stringent definition. The Watershed Association recognizes that landowners/users should be entitled to limited use of the stream corridor and therefore the logical approach would be to define permitted, prohibited and conditional uses within the stream corridor. Most stream corridor protection related initiatives permit farming within stream corridors. Impacts on water quality caused through farming activities can be reduced to a large extent by utilizing Best Management Practices (BMPs) such as maintaining a filter strip between streams and all farming activities. BMPs in farming should be promoted through the municipality or a related organization to farmers under the Right to Farm Act, receiving federal funding or receiving grain or other equipment subsidies. The appropriate municipal authorities should ensure the promotion of these BMPs, through workshops, literature or by exposure to organizations that conduct related programs (e.g., Consolidated Farm Service Agency, Natural Resources Conservation Service, Extension offices, State Forestry Agency or Soil Conservation District). Proper protection of stream corridors in our watershed is critical at this time to maintain not only the health of the stream corridor and its surrounding natural environment, but also for the health of the nearby communities and those who live in them. 1 Dave Rosgen, Applied River Morphology 3 (1996).