The Fall 2026 Donald RF Harleman Honorary lecture in Water Resources Engineering presents Witold “Witek” Krajewski, Professor Emeritus, Department of Civil and Environmental Engineering, University of Iowa.
Dr. Krajewski will present an overview of the key components of a generic streamflow forecasting system motivated by operational needs. He will start by defining the scope, the goals, and the key terms of the involved elements. These include a rainfall-runoff model, radar-based quantitative precipitation estimation (QPE), numerical weather model based quantitative precipitation forecasts (QPF), and streamflow data assimilation. Dr. Krajewski will provide brief background on each of these elements focused on operationally available products (in the U.S.) and their characteristics. The discussion of these models and products will be rooted in the basic hydrologic and meteorologic research and the existing challenges. The talk will be illustrated with analyses of the nation-wide streamflow forecasting data as well as hydrologic modeling results using tools developed at the Iowa Flood Center.
Dr. Witold F. Krajewski is Professor Emeritus in the Department of Civil and Environmental Engineering at the University of Iowa. Until recently, he was the Rose & Joseph Summers Chair in Water Resources Engineering and Research Engineer at IIHR—Hydroscience & Engineering. In 2009, he co-founded the Iowa Flood Center and served as its Director until 2024. Dr. Krajewski’s scientific interests concern measuring, modeling, and forecasting precipitation using radar and satellite remote sensing. His current research focuses on understanding the genesis and evolution of floods through field data and modeling, and the quantification of uncertainty in hydrologic prediction at a range of temporal and spatial scales.