Patrick L. Brezonik

headshot of Patrick Brezonic

Patrick L. Brezonik

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


  • B.S., 1963, Chemistry, Marquette University
  • M.S., 1965, Water Chemistry, University of Wisconsin-Madison
  • Ph.D., 1968, Water Chemistry, University of Wisconsin-Madison

Professional Background

  • Assistant, Associate, and Full Professor, Department of Environmental Engineering Sciences, University of Florida, 1966-81
  • Guest Professor, EAWAG-Swiss Federal Institute of Technology (ETH), Zurich, Switzerland, 1971-72 and summer, 1980
  • Professor, Department of Civil Engineering, University of Minnesota, 1981-2010.
  • Program Director for Environmental Engineering, National Science Foundation, Arlington, VA, 2004-2007
Research Interests

Research during my career focused on the impacts of human activity on water quality, including the biogeochemical cycles of nitrogen and phosphorus and the behavior of trace metal contaminants in large natural systems (watersheds and lakes). Field and laboratory studies, including experimental manipulations in large systems, were emphasized. More recent research was primarily in three areas: (1) applications of remote sensing (mainly satellite imagery) to evaluate lake quality, (2) dissolved natural organic matter, and (3) mercury biogeochemistry. I have continued to do research in the first two areas since my retirement. My work in satellite imagery has focused on regional analyses and long-term trend assessments of water clarity and measurement of dissolved organic matter and other water quality conditions in surface waters using Landsat and newer satellite platforms. Much of my past research was conducted through multi-disciplinary projects. For example, the experimental acidification of a lake in northern Wisconsin was done in cooperation with limnologists, fisheries biologists, and hydrologists from several institutions, and watershed-level research in the Minnesota River Basin was conducted with colleagues from several departments at the University of Minnesota.

Note: Professor Brezonik does not accept graduate students for advising anymore.

Honors and Awards


University of Minnesota, Fesler-Lampert Chair in Urban and Regional Affairs, 2003-4

Association of Environmental Engineering and Science Professors, Distinguished Service Award, 2004

US Geological Survey, Benchmark Award, for distinguished service to WRRI program, 2005

Universities Council on Water Resources, Warren Hall Medal, 2007

University of Minnesota, Dave Ford Water Resources Award, 2007

AAEES, Board Certified Environmental Scientist (BCES), by eminence, 2012


Brezonik, P. L. and W. A. Arnold. 2022. Water Chemistry: The Chemical Processes and Composition of Natural and Engineered Aquatic Systems, 2nd edition, Oxford University Press, New York, 976 p.

Brezonik, P. L. and W. A. Arnold. 2011. Water Chemistry: An Introduction to the Chemistry of Natural and Engineered Aquatic Systems, Oxford University Press, New York, 782 p.

Brezonik, P. L. 1994. Chemical Kinetics and Process Dynamics in Aquatic Systems. Lewis Publ.-CRC Press, Boca Raton, FL, 754 p.

Selected Publications

Germolus, N., P. L. Brezonik, R. M. Hozalski, and J. C. Finlay. 2021. Long-term water color and flow trends in the Mississippi River headwaters, 1944-2010. Limnol. Oceanogr. 66: 3552-3567.

Olmanson, L. G., B. P. Page, J. C. Finlay, P. L. Brezonik, M. E. Bauer, C. G. Griffin, and R. M. Hozalski. 2020. Regional measurements and spatial/temporal analysis of CDOM in 10,000+ optically variable Minnesota Lakes using Landsat 8 imagery. Sci. Tot. Environ. 724: 138141.

Chen, Y., R. M. Hozalski, L. G. Olmanson, C. G. Griffin, J. C. Finlay, P. L. Brezonik, and W. A. Arnold. 2020. Prediction of photochemically produced reactive intermediates in surface waters via satellite remote sensing. Environ. Sci. Technol. 54: 6671–6681.

Brezonik, P. L., J. C. Finlay, C. G. Griffin, W. A. Arnold, E. H. Boardman, N. Germolus, R. M. Hozalski, and L. G. Olmanson. 2019. Iron influence on dissolved color in lakes of the Upper Great Lakes States. PLoS ONE 14(2): e0211979.

Brezonik, P. L., R. W. Bouchard, Jr., J. C. Finlay, C. G. Griffin, L. G. Olmanson, J. P. Anderson, W. A. Arnold, and R. M. Hozalski. 2019. Color, chlorophyll a, and suspended solids effects on Secchi depth in lakes: implications for trophic state assessment. Ecol. Appl. 29(3):e01871.

Griffin, C. G., J. C. Finlay, P. L. Brezonik, L. G. Olmanson, and R. M. Hozalski. 2018 Limitations on using CDOM as a proxy for DOC in temperate lakes. Water Research 144: 719-727.

Brezonik, P. L., P. R. Bloom, R. L. Sleighter, R. M. Cory, A. R. Khwaja, and P. G. Hatcher. 2015. Analysis of chemical differences of aquatic humic substances extracted by XAD-8 and DEAE-cellulose. J. Environ. Chem. Engr. 3: 2982-2990.

Brezonik, P. L., L. G. Olmanson, J. C. Finlay, and M. E. Bauer. 2015. Factors affecting the measurement of CDOM by remote sensing of optically complex inland waters. Remote Sens. Environ. 155: 199-215. DOI: 10.1016/j.rse.2014.04.033.

Olmanson, L. G., P. L. Brezonik and M. E. Bauer. 2013. Airborne hyperspectral remote sensing to assess spatial distribution of water quality characteristics in large rivers: The Mississippi River and its tributaries in Minnesota. Remote Sens. Environ. 130: 254-265.

Khwaja, A. R., P. R. Bloom and P. L. Brezonik. 2010. Binding strength of methylmercury to aquatic NOM. Environ. Sci. Technol. 44: 6151-6156.

Dadaser-Celik, F., P. L. Brezonik, and H. G. Stefan. 2008. Agricultural and environmental changes after irrigation management transfer in the Develi Basin, Turkey. Irrig. Drainage Syst. 22: 47-66.

Olmanson, L. G., M. E. Bauer, and P. L. Brezonik. 2008. A 20-year Landsat record of water clarity in Minnesota’s 10,000 lakes. Remote Sens. Environ. 112: 4086-97.

Rockne, K. J. and P. L. Brezonik. 2006. Nutrient removal in a cold-region wastewater stabilization pond: importance of ammonia volatilization. J. Environ. Eng. (ASCE) 132 (4): 451-459.

Hines, N. A. and P. L. Brezonik. 2007. Input-output analysis of mercury forms for a small lake in northern Minnesota. Biogeochem. 84: 265-84.

Pilgrim, K. M. and P. L. Brezonik. 2005. Treatment of lake inflows with alum for phosphorus removal. Lake Reserv. Manage. 21: 1-11.

Fang, F., K. W. Easter, and P. L. Brezonik. 2005. Point-nonpoint source water quality trading: a case study in the Minnesota River basin. J. Am. Wat. Resources Assoc. 41: 645-58.

Brezonik, P. L., K. Menken, and M. E. Bauer. 2005. Landsat-based remote sensing of lake water quality characteristics, including chlorophyll and colored dissolved organic matter (CDOM). Lake Reserv. Manage. 21: 373-382.

Brezonik, P. L., C. E. Mach, and C. J. Sampson. 2003. Geochemical controls for Al, Fe, Mn, Cd, Cu, Pb, and Zn during experimental acidification and recovery of Little Rock Lake, Wis., U.S.A. Biogeochem. 62: 119-143.

Stadelmann, T. H. and P. L. Brezonik. 2002. Analysis and predictive models of stormwater runoff volumes, loads, and pollutant concentrations from watersheds in the Twin Cities (Minnesota, USA) metropolitan area. Water Res. 36: 1743-1757.

Kloiber, S. M., P. L. Brezonik, and M. E. Bauer. 2002. Application of Landsat imagery to regional-scale assessments of lake clarity. Water Research 36: 4330-4340.

Fang, F., P. L. Brezonik, D. J. Mulla, and L. K. Hatch. 2002. Estimating runoff phosphorus loss in the Minnesota River Basin. J. Env. Qual. 31: 1918-29.