Observer rating of recreational use in wadeable streams of New York State, USA: Implications for nutrient criteria development

摘要

Like most other States and Tribes in the United States, New York State has been working with the United States Environmental Protection Agency to develop numeric nutrient criteria. These criteria are to protect water use such as drinking water supply, aquatic life, and recreation. Although extensive research exists related to the effects of eutrophication on human health and aquatic life, limited information is available on perceived impairment of recreational opportunities in rivers and streams. We present an approach to assess impacts to recreation using information collected by New York State's (NYS) monitoring program. This approach involved a questionnaire adapted from lake management surveys in which field crews rated their perceptions of recreational ability at each site. The ratings were then used to assess the relationship between perceived impact to recreational use and water quality. We include in our analyses the primary nutrient criteria variables total phosphorus (TP), total nitrogen (TN), suspended chlorophyll-a (SChl-a), and turbidity (Tb), as well as biological condition (benthic macroinvertebrate community assessment). We sampled 203 wadeable stream locations throughout NYS between July and September 2008 -2012. Field crews ranked most locations as having "Minor aesthetic problems," but still considered them excellent for both primary (34%) and secondary (37%) contact recreation. Field crew rankings of recreational ability coincided with a gradient of nutrients (TP and TN), SChl-a, and Tb concentration. Logistic regression models were developed that identified significant predictors affecting field crew decisions about recreation. These included water clarity, periphyton cover, and odor. Analysis of variance using NYS's multimetric assessment of biological condition and a nutrient specific community metric suggest significant differences in metric scores among recreational use categories. These results indicate correlation of impairment of recreational use with impairment of aquatic life use from nutrient enrichment. The results of this investigation will be used to help establish nutrient endpoints for the protection of recreation in NYS streams and rivers.