You have probably seen degraded streams. The banks of the stream are steep, and often times, eroding. Excessive sediment smothers aquatic habitats.
The degradation may have been caused by stormwater runoff, increased sediment load caused by the removal of trees or other development activities, or by changes in the amount of water the stream transports due to increased development and built-upon area.
Typically, only a few species of fish and aquatic life can live in these impacted streams. Degraded streams can lead to water quality declines over entire watersheds and are unhealthy for recreation and public contact.
To restore or stabilize a stream, a team of scientists, engineers, and surveyors analyze the watershed where the stream is located and survey the current condition of the stream. Then, based on the results of the analysis, a design is developed to help restore the stream to a more “natural” form. This means that the stream is designed to neither erode the stream channel and banks nor accumulate sediment in the channel over time.
During a stream restoration, a new stream channel is constructed, a new floodplain is developed, and new vegetation is planted along the stream banks. Stream restoration means to re-create meanders, stabilize soil, and install gently sloping stream banks. Stream restoration is not always possible due to constraints such as utility crossings, structures, and roadways.
Two agencies are responsible for restoring streams in Greensboro: the NC Ecosystem Enhancement Program and the NC Department of Transportation. Details about their specific projects are listed below.
North Carolina Ecosystem Enhancement Program
The North Carolina Ecosystem Enhancement Program (EEP) has restored more than 16,000 linear feet of streams in five Greensboro City parks. Projects in Benbow Park, Brown Bark Park, Gillespie Golf Course, Price Park, and Hillsdale Park have used natural stream restoration methods to stabilize stream channels, improve water quality, and increase habitat for fish and other aquatic life.
North Carolina Department of Transportation
The North Carolina Department of Transportation (NCDOT) constructs many miles of highways and roads each year. Although NCDOT is dedicated to preserving North Carolina's natural resources, impacts to streams and other valuable natural areas are sometimes unavoidable. When a project affects a stream, NC General Statutes require that the NCDOT compensate for these impacts through mitigation. The goal of mitigation is to design adjustments to the stream reach that will increase long-term stability and create a more functional riparian ecological community.
NCDOT has restored several impacted segments in five Greensboro City parks. The projects, in Spring Valley, Starmount Forest Country Club, Sussman Park, Starmount Park and Lindley Park, have converted unstable, altered or degraded stream corridors back to their natural or stable condition by restoring geomorphic dimension, pattern, and profile, as well as biological and chemical integrity.
During a stabilization or enhancement, an attempt is made to stabilize the stream without greatly altering the location. Stabilization and enhancement is done when constraints are present in urban areas that do not allow for a full restoration project. Stabilization will employ some restoration methods, such as sloping the banks and re-vegetating. However, stabilization employs the use of man-made structures to help direct stream flow away from banks. These types of structures help to alleviate bank stress and help to improve water quality and habitat for beneficial stream bugs and fish. Stabilization can also employ the use of bioengineering to help stabilize banks. Bioengineering is the use of both special plants and products that help stabilize the soil by plant root growth.
City of Greensboro
In addition, the City of Greensboro is responsible for stream stabilization and enhancements. Through a detailed evaluation of stream bank erosion and water quality, the City determines which erosion and stream projects are viable for stabilization and enhancement. A list of current projects is below: