Stream Protection Strategy Monitoring Status
Baseline Monitoring Status
A compilation of protocols for stream monitoring was completed in March 1999 and revised in November 1999. A draft document with the protocols has been completed and is available for download (see Technical Background for details). Stream sampling for benthic macroinvertebrates commenced in March 1999 for the Baseline Study and was completed at the end of May 1999 for all sites in Fairfax County. Fish sampling for all sites was completed at the end of October 1999. Concurrent with fish sampling was the stream habitat and physical morphology assessments which was also completed by end of October 1999. The identification of benthic macroinvertebrate samples collected was conducted by laboratory analysis and was completed by the end of July 2000.
During the summer of 1999, the region experienced one of the most significant droughts on record. Because the unusually low flow had the potential to influence fish samples obtained during that time period, 25 percent of the sites were randomly selected from subgroups based on stream order and were re-sampled in the summer of 2000. No significant differences between samples of both years were noted.
Future Monitoring Program
Protecting and restoring stream quality within Fairfax County will require a diverse management approach that includes an active and ongoing stream monitoring effort, targeted restoration activities, public education, improving stormwater controls, and enhancing channels of communication with the development community. Some of these steps have already commenced. The Baseline Study should be viewed as the beginning phase of a permanent long-term monitoring effort that will be needed for better management of aquatic resources within the county.
In the spring of 2001, the Stream Protection Strategy team initiated the second round of monitoring that includes sampling approximately 25 percent of existing sites and new sites designated as "priority assessment" areas. The long-term plan is to continue monitoring of streams in the county on a four to five year rotational basis to help determine future trends in stream quality and evaluate management strategies.
Components of any future Stream Protection Strategy program will likely involve the following:
- Continued monitoring of existing Stream Protection Strategy sites on a rotating basis involving 20-25 percent annually;
- Establishing a detailed visual assessment program at the subwatershed level;
- Assessing variables influencing fish community composition and distribution;
- Promoting the expansion of volunteer monitoring efforts;
- Defining and identifying additional perennial streams within the county;
- Assisting with the evaluation and implementation of innovative Best Management Practices;
- In stream sediment studies, stream morphological assessments and better mitigation for stream erosion problems;
- Periodic reassessment of imperviousness within watersheds;
- Improving inter-agency cooperation regarding sediment control implementation and maintenance;
- Public education that fosters community interest in stream ecology and stewardship.