Design methodology accounting for the effects of porous medium heterogeneity on hydraulic residence time and biodegradation in horizontal subsurface flow constructed wetlands A. Brovelli1, O. Carranza-Diaz, L. Rossi, D.A. Barry Laboratoire de technologie écologique, Institut d’ingénierie de l’environnement, Ecole Polytechnique Fédérale de Lausanne (EPFL), Station No. 2, CH-1015 Lausanne, Switze...