This book contains the selected extended abstracts presented at the First International Workshop on Environmental Hydraulics IWEH09, Theoretical, Experimental and Computational Solutions, held in Valencia from 29 to 30 October 2009. The aim of the workshop was to encourage scientists, engineers and researchers to present and facilitate communication on modeling environmental problems related to hydrodynamic aspects of fluid modeling, including fluid mechanics analysis, transport of pollutants, mathematical and system modeling, experimental and theoretical validation experiences,...