Monitoring Benthic Macroinvertebrates in Urban Stream Restorations 2010-2024
Chris Ruck
Fairfax County (VA) Watershed Assessment Branch
Fairfax VA
After the adoption of the Chesapeake Bay TMDL in 2010, Fairfax County increased efforts to restore urban stream channels using the best available technology. Most frequently, the implemented restorations are NCD threshold channels that primarily prevent lateral migration and are effective at reducing erosion. However, the County also wanted to learn if the stream restoration projects could also improve biology.
This presentation discusses the evolution, status, and results of a municipal stream restoration benthic macroinvertebrate monitoring program from 2010 to present. To comply with the TMDL, Fairfax County increased the number of projects per year, currently anticipating funding at least six new projects, estimated around $20 million annually. Due to the large and ever-increasing volume of stream restorations in the municipal inventory, staff developed a project-specific monitoring program using intra-agency coordination, prioritization scheme for selection, and a rigorous experimental design. Implemented in 2015-16, the monitoring approach needs at least seven years to effectively comment on the post-restoration biological condition of each site.
Fairfax County currently has over 60 proposed or constructed stream projects with pre-restoration benthic monitoring data and over 25 streams with post-restoration information. These data are holistically compared to countywide averages, and pre- vs. post- analyses of individual projects to identify differences. These analyses will also highlight any trends and changes to macroinvertebrate assemblages that can be attributed to urban stream restoration.
About Chris Ruck
Coming Soon