Stream identification is rarely as simple as looking for the blue lines on a map. Practices to identify and assess streams vary throughout the United States. A lot can change between different State and Federal agency jurisdictions. In order to do these types of assessments, it is necessary to have knowledge of specific methods for determination of jurisdiction and flow regime.
Flow regimes can include perennial, intermittent and ephemeral flow. Depending on the location, season and recent weather, these regimes can be difficult to differentiate and the streams themselves may be hard to recognize. For example, this stream in Harlan Co., KY only carries flow in response to rainfall. Differing agencies on the State and Federal levels may treat an aquatic resource such as this in different ways.
Another factor is policy change. Legal jurisdiction over aquatic features can vary based on the current policies.
BSC is dedicated to being up to date with the current policies of State and Federal agencies in order to make accurate and efficient determinations. The staff has practiced a variety of different assessments to determine the flow regimes and functionality of aquatic resources throughout multiple states. BSC works hard to ensure that various permitting processes are accomplished successfully.
Many methods are utilized in the process of restoring a stream. The complete reconstruction of a stream can bring the work of builders, engineers, GIS professionals and biologists together to create a natural stream design.
Installation of in-stream structures is very important to create wildlife habitat and prevent erosion while maintaining aesthetics. In-stream structures can include: deflectors, cross-vanes, weirs, step pools and log jams. These structures can be used to direct stream flow, dissipate flow energy, and create pools and other habitats for aquatic species.
Several elements of stream restoration can be seen in this image: The boulders concentrate flow down the center of the channel to reduce bank erosion. Cross-vanes reduce velocity and add diversity to the water flow. Meanwhile, large local woody debris was placed throughout the reach to provide amphibian habitat and food to macroinvertebrates in the form of detritus as they decompose.
BSC has been involved in all aspects of stream restoration including the design and monitoring of in-stream structures for reconstructed streams.
Riparian zones include the plant communities along stream and river banks. Riparian zone health directly affects stream health by preventing erosion and promoting habitat biodiversity. Riparian zone plantings are integral, and often required, for stream mitigation, restoration, and enhancement. Plant species of all strata can be used to help create a healthy riparian zone. Species selection is based on ecosystem, wildlife benefit, cost effectiveness, and availability.
BSC has helped to plan, implement, coordinate and monitor many riparian zone plantings in order to re-establish healthy stream ecosystems in impacted areas. A healthy riparian zone promotes stream health through canopy cover, nutrient cycling, invasive species prevention and much more.