Acta Geophysica vol. 61, no. 1, Feb. 2013, pp. 194-210 DOI: 10.2478/s11600-012-0051-7 ________________________________________________ © 2012 Institute of Geophysics, Polish Academy of Sciences Application of One-Dimensional Model to Calculate Water Velocity Distributions over Elastic Elements Simulating Canadian Waterweed Plants (Elodea Canadensis) Elżbieta KUBRAK 1 , Janusz KUBRAK 1 , and Paweł M. ROWIŃSKI 2 1 Faculty of Civil and Environmental Engineering, Warsaw University of Life Sciences, Warszawa, Poland e-mails: Elzbieta_Kubrak@sggw.pl, Janusz_Kubrak@sggw.pl 2 Institute of Geophysics, Polish Academy of Sciences, Warszawa, Poland e-mail: pawelr@igf.edu.pl Abstract One-dimensional model for vertical profiles of longitudinal veloci- ties in open-channel flows is verified against laboratory data obtained in an open channel with artificial plants. Those plants simulate Canadian waterweed which in nature usually forms dense stands that reach all the way to the water surface. The model works particularly well for densely spaced plants. Key words: submerged flexible vegetation, velocity profile, open- channel flow, Canadian waterweed. 1. INTRODUCTION The search for relevant velocity profiles in free surface flows is still a key and debatable issue in hydraulic research (Meyer 2010, 2011, Castro-Orgaz and Dey 2011) and it is particularly challenging when one deals with vege- tated channels. The authors of this study have developed a one-dimensional model for the computations of vertical velocity profiles of flows through