We are an informal, interdisciplinary group of faculty, staff scientists, students and postdocs from three University of Minnesota colleges, who collaborate on developing procedures to measure water quality of inland waters (lakes and rivers) by satellite imagery. We also analyze the satellite-derived data to develop better understanding of spatial and temporal variations in water quality, especially at large (ecoregion) scales. In the more than 20 years our core group has worked together we have seen vast improvements in satellite technology and in the techniques used to retrieve useful water quality information from satellite imagery. Our work has contributed significantly to the development of the field from a new and untested science area to a mainstream approach for obtaining regional scale water quality data.  

marvMarvin Bauer

Professor Emeritus of Remote Sensing
Department of Forest Resources

Marvin Bauer is professor emeritus of remote sensing at the University of Minnesota. His research has emphasized the development of quantitative satellite remote sensing for monitoring lake water quality, crop and forest inventory, impervious surface mapping, and land cover classification, change detection and analysis. He is a fellow of the American Society of Photogrammetry and Remote Sensing and recipient of the USGS/NASA William T. Pecora Award, NASA Distinguished Public Service Medal, ASPRS SAIC Estes Memorial Teaching Award, and Minnesota GIS/LIS Consortium Lifetime Achievement Award. He was editor-in-chief of Remote Sensing of Environment journal from 1980-2014.

patrick brezonikPatrick Brezonik

Professor Emeritus
Department of Civil, Environmental, and Geo-Engineering

Patrick Brezonik is an emeritus professor of environmental engineering at the University of Minnesota. He retired in 2010 after a career at the University of Florida and University of Minnesota. Trained as an aquatic chemist, he remains active in research and professional activities. His research has focused on improving understanding of major water quality issues, such as lake eutrophication, acid rain and lake acidification, and biogeochemical cycling of mercury and other heavy metals. He is the author/co-author of two water chemistry texts and numerous technical articles and served as Director of NSF’s Environmental Engineering Program from 2004 to 2007. As director (1985-2003) of the University of Minnesota's Water Resources Center, he played a key role in establishing the graduate program in Water Resources Science. He has conducted research on remote sensing applications to measure water quality of lakes and rivers since 1997.


leifseptLeif Olmanson

Research Associate
Department of Forest Resources and Remote Sensing and Geo-Spatial Analysis Laboratory

Leif Olmanson is a research associate specializing in remote sensing techniques at the University of Minnesota. He has more than 20 years of experience developing remote sensing applications to create multi-temporal, spatially comprehensive datasets of water and land resources to characterize large ecosystems and ecoregions, and he has authored/co-authored many highly cited articles on these topics. Applications include lake and river water quality and aquatic plant assessments using multispectral and hyperspectral imagery, and land cover mapping using multispectral imagery and lidar data with object-based image analysis using random forest classification,. His current research focuses on new, enhanced satellite systems, such as Landsat 8 and Sentinel-2 to measure colored dissolved organic matter (CDOM), chlorophyll and non-algal suspended sediments in optically complex inland waters across broad regional scales. He is particularly interested in using cutting edge geospatial analysis to improve understanding of the natural environment.

BenBen Page

Research Fellow
Water Resources Center

Benjamin Page is a research fellow in the Water Resources Center at the University of Minnesota. He has an extensive background in satellite-based remote sensing and geospatial analysis of inland waters. During his M.S. studies in Geography at the University of Georgia he participated as a project lead at NASA DEVELOP, and then he joined NASA SERVIR as a regional science associate, evaluating strategies to implement satellite-based remote sensing for monitoring of inland water quality in developing regions. His current work focuses on calibrating Landsat and Sentinel imagery to characterize optically active constituents in Minnesota’s > 10,000 inland water bodies.


jacquesJacques Finlay

Department of Ecology, Evolution and Behavior

Jacques Finlay is professor of ecosystem ecology at the University of Minnesota. His research investigates the ecology of freshwater ecosystems and their interactions with surrounding natural and human-altered landscapes. His lab does interdisciplinary, collaborative research that integrates across spatial and temporal scales.  Current research areas include investigation of productivity and energy flow in river food webs, urban biogeochemistry, CDOM dynamics in lake systems, carbon and nutrient cycling in lakes, management strategies for comprehensive water quality improvement in the Midwest, and use of satellite imagery to obtain spatially comprehensive data on key water quality parameters, including chlorophyll, CDOM, and total suspended matter. He is the principal investigator on our current LCCMR project that is developing methods to map concentrations of the above water quality variables across Minnesota’s lake environments. Additional information is at:


claire griffinClaire Griffin

Postdoctoral Research Associate
Department of Ecology, Evolution, and Behavior  

Claire Griffin began a new postdoc position at the University of Virginia in February 2019, working on interactions between built and natural environments in the Arctic. She joined the University of Minnesota in 2016 as a postdoctoral researcher in Ecology and works on our current NSF and LCCMR grants. Her research focuses on linking watershed characteristics to water quality in inland and coastal waters, with an emphasis on organic matter and carbon cycling. She is interested in using optical characteristics to monitor water quality, through field, lab, and remote sensing techniques. Her research has addressed these issues in Arctic, Midwestern, and coastal Texas waters. Previous to her current position, she completed her Ph.D. in Marine Science at the University of Texas at Austin in May 2016.

rayhozalskiRaymond Hozalski

Department of Civil, Environmental, and Geo-Engineering

Raymond M. Hozalski is Professor of Environmental Engineering at the University of Minnesota. His research focuses primarily on biological processes for the treatment of water, wastewater, and hazardous waste. He is especially interested in the study of bacterial biofilms, which are microbial communities immobilized on solid surfaces. The main application area of Dr. Hozalski’s biological processes research concerns drinking water treatment and distribution. His research group also is active in studying the effects of dissolved organic matter, including CDOM, on water treatment processes such as coagulation, filtration, and disinfection (i.e., chlorine demand and disinfection byproducts). He regularly works with water utilities in the U.S. and abroad on applied research projects and as a consultant. Dr. Hozalski was recently appointed to the Drinking Water Committee of the USEPA Science Advisory Board. He also serves on the Board of the International Humic Substances Society and is a managing editor of the journal Biodegradation. He is the PI of our current NSF grant that is using satellite imagery to evaluate spatial patterns and temporal trends of CDOM across three major ecoregions encompassing northern Minnesota, Wisconsin and Michigan and leads the component on the effects of CDOM on drinking water treatment. 

williamarnoldWilliam Arnold

Professor and Associate Head
Department of Civil, Environmental, and Geo-Engineering

Bill Arnold is a Distinguished McKnight University Professor and Joseph T. and Rose S. Ling Professor at the University of Minnesota. He received his S.B. in Chemical Engineering from MIT (1994), M.S. in Chemical Engineering from Yale (1995), and Ph.D. in Environmental Engineering from the Johns Hopkins University (1999). His research focuses on the fate of organic chemicals in natural and engineered aquatic systems. Specific research areas include studying the kinetics, pathways and mechanisms of anthropogenic chemical reactions that occur at surfaces or via photochemical processes; the role of NOM and CDOM in affecting photolysis of anthropogenic chemicals; evaluating mass transfer effects on reaction rates; developing new remediation/containment techniques; and using computational chemistry techniques to predict and/or explain experimental observations. He is an Associate Editor of Environmental Science & Technology Letters. More details are available at:

yiling chenYiling Chen

Postdoctoral Research Associate
Department of Civil, Environmental, and Geo-Engineering

Yiling Chen is a postdoctoral associate in environmental engineering at University of Minnesota. Her research focuses on the fate and transformation of environmental contaminants in natural and engineered aquatic environments and their removal from surface water used for drinking water and wastewater effluents, as well as computational chemistry. She received her PhD from Temple University in late 2016 and immediately joined our group, working with Profs. Raymond Hozalski and William Arnold on the effects CDOM on drinking water quality, specifically on the formation of disinfection byproducts and the fate of aquatic pollutants in Minnesota. She has published in a variety of journals, including three papers in the leading environmental science journal, Environmental Science & Technology.