E PA/601/F24/003 *>EPA United States Environmental Protection Agency epa.gov/research Introduction EPA's Experimental Stream Facility (ESF) is one of only a few research facilities in the United States designed for conducting ecotoxicology research using stream mesocosms, which are experimental systems designed to simulate the natural environment but under tightly controlled conditions indoors. A precisely controlled setup allows for dose-response studies that can evaluate and validate the effects of suspected contaminants on native biotic stream communities. The facility allows researchers to study the impacts of emerging contaminants, mixtures, and nutrient pollution on multiple interacting species. ESF is also used to conduct studies related to water quality standards and the establishment of aquatic life criteria. This research helps inform decisions and management practices that affect the biodiversity and health of streams and their watersheds. ESF research supports EPA's National Research Programs, which provide the scientific foundation for decision-making to safeguard human health and the environment. Mesocosm studies at ESF are designed in response to EPA program office, partner, and stake- holder needs. Facility and Staff Facility: ESF includes 3,800 square feet of laboratory, office, and research space, and is on long-term lease from Clermont County, Ohio. The facility sits adjacent to the Lower East Fork - Little Miami River Regional Waste Water Treatment Plant, on land in the upper floodplain terrace of the lower East Fork of the Little Miami River watershed. Staff: ESF houses three full time federal employees and contractors. During experiments additional scientific and support staff are on site. Mesocosm An experimental system that examines the natural environment under controlled conditions. ESF stream mesocosms are colonized with native species to provide a realistic model of riffle/run habitat of a natural stream. Mesocosm studies are designed to assess effects on biotic communities and provide a link between field surveys and bench-top laboratory experiments. Capabilities ESF contains analytical equipment and instrumentation used to link pollutant loads to in-stream biological conditions. Several features that make the ESF unique among stream mesocosm facilities include: • An indoor setup of sixteen 28-foot stream channels that can be dosed independently of one another; • Multiple continuous water sources, including a natural source from the river, reverse osmosis treated tap water, and final treated effluent from the adjacent wastewater treatment plant. Each source can be precisely metered to produce different mixing conditions; Experimental set up and sampling in the mesocosms Connect with us Online D d # ------- Facility Contact: Dr. Chris Nietch, nietch.christopher@epa.gov £EPA Watershed Research & Cooperative The ESF serves as a base of operations for the East Fork of the Little Miami River Watershed Study (EFWS) — a case study that supports a long-term water quality monitoring program, numerous field studies, and watershed-scale analyses. The ESF sits at the downstream end of the East Fork of the Little Miami River Watershed. The EFWS research is managed by the East Fork Watershed Cooperative, a multi-agency partnership that includes scientists, engineers, water resource professionals, and stakeholders. Through the EFWS, the Cooperative co-produces research on the utility of watershed management models, addresses the risks posed by harmful algae in its multi-use reservoir (Harsha Lake), minimizes excess nutrient runoff and other contaminants of concern, works to protect drinking source water, and designs and implements innovative agricultural best management practices for reducing nutrient pollution. Science Contributions The unique research conducted at ESF identifies links between environmental stressors in stream flow and the structure and function of stream ecosystems. ESF is used by scientists to understand interactions between environmental stressors and stream organisms, and to predict the movement and transformation of pollutants in surface water. Continuous water quality monitoring; High and low intensity grow lights to simulate open canopy and shaded forest canopy sunlight; Protocols for capturing macroinvertebrate drift and insect emergence and assessing the micro- and macroorganism communities at the whole mesocosm scale; Chemical dosing system for precise delivery of chemicals/stressors and influent mixing; and Supervisory Control and Data Acquisition system consisting of water quality sensors, valves, and meters to set experimental triggers, automate data collection, and monitor and control flows, lights, and chemical delivery. Active research topics include: • Testing that supports nutrient criteria development for the protection of aquatic life. • Freshwater oil spill simulations and tracking of ecological consequences. • Methods development for assessing risks posed by harmful algal blooms. • Development of DNA-based indicators for stream bioassessment. Notable scientific products & achievements in- clude: • Studies that demonstrated the effects of antimicro- bials on stream biotic communities, including increases in antimicrobial resistance and ecological impacts, which contributed to the removal of Triclosan from soap products. • Validating a field benchmark proposed for streams receiving discharges of excess major ions from mines. • Designing a parallel single-species exposure format that helps validate the appropriateness of laboratory toxicity assays. • Testing new methods for contaminant sensing and means of measuring important biological process in situ, • Incorporating community-level endpoints that inform effects on stream functional responses. • Determining natural stream processes important to the utility of DNA-based indicators of fecal pollution. Connect with us Online # •• You inrci ------- |