Stream - Riparian Rapid Assessment

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riparian plants may walls the 200m Upper and Lower Riparian transects, while another team member who is more familiar with fluvial morphology and aquatic habitats can take measure- ments along the 200m in-stream transect. The Overall Comments section at the end of the score sheet should be used to discuss the gen- eral conditions of the stream, as well as any extreme or unexpected conditions that are observed during the survey. These comments can be a very useful verbal summary of the most important findings of the assessment After the initial data are collected on the worksheets, all members of the team should meet to discuss their evaluations and scoring assigiunent for the Assessment Score Sheet, as well as any recommendations the team may make for the possible future restoration of the reach. It is important to emphasize that variables are scored entirely on the basis of existing conditions within the reach and not on any potential or hypothesized future condition. An additional worksheet on Human knpacts is included as Appendix 4. Tlus worksheet should be used to take note of various types of human activities and impacts that are occurring on the study reach or adjacent areas. This information is not used in the scoring because the RSRA method is specifically designed to measure the current ecological functioning and condition (health) of the reach, regardless of how those conditions came about. However, it can be useful to take note of human-related impacts in the stream channel and floodplain, as these may explain why certain indicators may receive low functional scores. This information may also provide suggestions for future restoration projects if needed. 5. Tallying the Scores and Interpretation After completing all the field surveys, the observation team should rate each indicator from 1 to 5, using the scoring definitions on the Score Sheet. Then, for each category, calculate and record the mean score for that set of indicators in that section and on the last page. The overall score for the surveyed stream reach is then obtained by calculating the overall mean of the five category mean scores. An overall mean score of 1-2 indicates that most or all components of the stream are not func- tioning and that the reach probably cannot provide many of the values of healthy stream-ripari- an ecosystems. Scores of 2-4 indicate that some components may be in healthy condition while others are not, and/or that the entire system in general has been impacted by human activities or natural disturbances in the past, but it is now in a transitional state. The direction of the change, and whether the system is improving or getting worse, can oiily be determined by subsequent visits and monitoring programs. Scores of 4-5 indicate that the ecosystem is healthy and that it matches what would be expected in a geomorphically similar reference reach or in an unim- pacted "presettlement" condition. Because of the dynamic nature of stream-riparian ecosystems, it is very unlikely that any reach, even one in pristine condition, would obtain a mean score of 5 for any category or overall, and this should not be expected. While a single composite site score is desirable for judging site health and developing regional 13