December 17th Stormwater Seminars
Title: Pollutant Removal and Maintenance Assessment of Underground Filtration Systems (Phase I)
Presented by: Todd Shoemaker & Ali Stone, Wenck
In this presentation, we will present our preliminary data and conclusions from the summer of 2020. We collected samples from six different storm events to evaluate pollutant removal and recorded water levels during the summer of 2020 to measure filtration (drawdown) rates.
The purpose of this study was to evaluate the stormwater management effectiveness of four underground sand filters in the Twin Cities Metro Area. These types of filters do not always offer clear access to the sand media layer and are not included in the Minnesota Stormwater Manual. Therefore, their pollutant removal effectiveness and maintenance frequency are somewhat unknown.
Mr. Shoemaker has nearly 20 years of experience in water resources and environmental engineering. His water resources expertise includes watershed and stormwater management, hydrologic/hydraulic and water quality computer modeling, floodplain management and regulation, wetland restoration and permitting, as well as streambank stabilization.
Ms. Stone is a current student at the University of Minnesota, pursuing a degree in Civil Engineering with a water resource emphasis. As an intern with Wenck, she has completed pond maintenance surveys; stream and lake monitoring; and water quality data analysis. Ms. Stone served as the primary field investigation staff for this study.
Title: Temporal Dynamics of Pathogens and Antibiotic Resistance Genes in Raw and Treated Stormwater
Presented by: Satoshi Ishii - Associate Professor, Department of Soil, Water, and Climate, University of Minnesota
Stormwater is considered as an alternative water source for both potable and non-potable uses. However, stormwater has not been widely used as an alternative water source, most likely due to a lack of knowledge about the presence and risks associated with pathogens and antibiotic resistance genes present in raw and treated stormwater and how these populations change with environmental conditions. Five different stormwater reuse systems in the Twin Cities metro area were sampled from every three weeks from June to October 2019 to build a comprehensive data set for analysis of temporal dynamics of pathogens and antibiotic resistance genes (ARG) in raw and treated stormwater samples. Microfluidic qPCR, a high-throughput quantification tool provided microbial data for 12 bacterial pathogens, 11 viral pathogens and 48 ARGs along with physiochemical testing such as turbidity, free and total chlorine, and water temperature to evaluate environmental conditions. The calculated pathogen and ARG removal efficiencies for each stormwater reclamation processes compare how well these contaminants can are removed by different stormwater reclamation systems. Correlations between pathogen and ARG levels and environmental parameters such as temperature and precipitation assess the impact of precipitation and other environmental variables on pathogen and ARG concentrations in stormwater.
Dr. Satoshi Ishii is an Associate Professor in the Department of Soil, Water, and Climate as well as the BioTechnology Institute at the University of Minnesota. He started working at the U of M in 2015. Prior to joining the U of M, he was Assistant Professor in the Division of Environmental Engineering in Hokkaido University, Japan, and a postdoctoral research associate in the University of Tokyo, Japan. He received his B.S. from the University of Tokyo, Japan, M.S. from Iowa State University, and Ph.D. from the University of Minnesota. His research focuses on environmental microbiology and biotechnology. The goal of his research is to solve key environmental problems, specifically (1) nitrogen pollution and (2) the occurrences of pathogens in soil and water environments.