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Larry A. Roesner, PhD.


Emeritus Professor  Civil and Environmental Engineering

Contact Info

Phone: (970) 491-7430   Office: Engineering A214

Email:   Lab:


Fields of Expertise

1.) Hydraulics
2.) Models, GIS, and Data

Areas of Interest

 Civil infrastructure systemsGraywater use in urban settingsSustainable urban water resource systems


Dr. Roesner's area of specialization since 1970 has been urban hydrology and nonpoint source pollution control. He is a principal developer of the Corps of Engineers model STORM, a simplified urban stormwater management model, and EPA's SWMM EXTRAN model, a sophisticated flow-routing model for urban drainage systems. Applications experience includes nonpoint source pollution studies in California, Michigan, Georgia, and Florida, and storm drainage/combined sewer studies in Seattle, San Francisco, Boston, Cincinnati, Detroit, Cleveland, Omaha, and many Florida cities. International experience in these areas includes Germany, Scotland, Romania, Uruguay and Brazil. He also has considerable experience with time series analysis of hydrologic records and has developed stochastic models of monthly precipitation and runoff. Another of Dr. Roesner's areas of specialization is water quality simulation of surface water bodies. Dr. Roesner is the principal author of QUAL-II, a stream water quality model developed for USEPA which simulates 11 water quality parameters. He has conducted a number of USEPA-sponsored workshops on the application of QUAL-II and has experience with model applications throughout the United States and Canada plus applications in Romania, Uruguay and Brazil. QUAL-II has been used extensively for wasteload allocation studies throughout the United States. Other major responsibilities include the development of a reservoir temperature model and the application of Ecologic-Water Quality Models to Monterey Bay, California, Puget Sound, Washington, and Montevideo, Uruguay to study the effects of discharges from proposed ocean outfalls on the receiving waters in these areas. Dr. Roesner's current research addresses developing improved methods of urban runoff management, so that urban drainage systems can be turned into urban water resources that are a community amenity and also provide aquatic ecosystem protection/enhancement. He is also researching residential graywater reuse for residential landscape irrigation and toilet flushing.