Water Resources Research Act Program

Details for Project ID 2020OK198B

Investigation of Indicator Bacteria in Oklahoma Streams

Institute: Oklahoma
Year Established: 2020 Start Date: 2020-03-01 End Date: 2021-02-28
Total Federal Funds: $25,000 Total Non-Federal Funds: $50,000

Principal Investigators: Jason Vogel

Abstract: With more than 167,000 miles of rivers/streams and 55,000 miles of shoreline, Oklahoma is known for its limitless water recreation and tourism opportunities. However, due to a variety of anthropogenic and wildlife impacts to water resources, pathogens can become a potential hindrance on water quality for the many beneficial uses of streams and rivers. Oklahoma currently has over 7,500 stream miles that are listed on the 2016 303(d) list for both E. coli and enterococci. Indicator bacteria, enterococcus and E. coli, are used as a measure to determine potential fecal contamination in freshwater streams and rivers for USEPA 303(d) impairment determination and beneficial uses. Due to the significant costs required to develop total maximum daily loads (TMDLs) and other state/local mitigation measures for impaired waterbodies and watersheds, it is important to understand the problem sources of constituents in order to properly address how to best resolve or manage watershed water quality. Many of Oklahoma’s streams and rivers are not routinely monitored for pathogenic indicators and can remain on the 303(d) list for decades without re-evaluation. The potential impact on water recreation and tourism opportunities is significant, and without potential alternative solutions, the economic and environmental impact could be detrimental to state growth and sustainability of quality water resources. Therefore, the goals of this project are to evaluate enterococcus as an indicator species for impairment determination and potential sources and environmental factors that influence enterococcus survivability in streams and rivers.This project will expand the limited information and research that is currently available regarding enterococcus bacteria as an indicator bacteria in Oklahoma streams and rivers. To the PI’s knowledge, there is no known work available that evaluates environmental factors, both spatially and temporally, for enterococcus survivability and sources in streams and rivers, specifically in Oklahoma. This research will build upon prior work that has questioned the enterococcus and fecal indicator sources and relating temporal/spatial chemical and physical factors to lead answering the question if we should reconsider impaired waterbody determinations. Three streams from at least two ecoregions (total of 6) will be monitored biweekly for a period of 20 weeks for enterococcus (total of 10 site visits/samples collected) in the stream water column and benthic substrate at the thalweg. Stream sites will be selected to represent varied site conditions (e.g. urban, rural, ecoregion) and stream reaches will be impaired for both enterococcus and E. coli on the most recent 303(d) list. Sampling visits will be conducted during expected baseflow conditions, based on measured stream flows, water quality and antecedent dry periods. Specifically, water quality parameters (pH, DO, temperature, conductivity, turbidity, TSS), habitat assessment (substrate, vegetative cover, periphyton, pollutants, etc.), stream flow, and precipitation (Mesonet stations) will be collected along with bacteria water and sediment samples. Field sampling will be completed in conjunction with the Oklahoma Water Survey’s (OWS) routine bacteria sampling schedule for impaired waterbodies and will require collecting additional enterococcus water and substrate samples for phenotypic analyses. A microcosm study will be setup for a duration of 30 days to replicate stream conditions in a controlled environment to understand survivability of bacteria colonies. Sample results and water quality data will be evaluated using a Pearson correlation coefficient to determine if factors are related and ANOVA to compare difference among group means among samples. Finally, results will be presented at a state and regional/international conference and will be published as a refereed journal article. The resulting information could lead efforts to further evaluate whether enterococcus is a quality indicator species for impairment determination of freshwater bodies in Oklahoma, and potential next steps for interpretation, revision, and/or further research to effectively administer state water quality standards for pathogenic indicators.