1. Dep. of Civil and Environmental EngineeringUniv. of Perugiavia G. Duranti 93PerugiaItaly
2. TU Wien, Centre for Water Resource SystemsKarlsplatz 13, A‐1040ViennaAustria
3. Federal Agency for Water ManagementInstitute for Land and Water Management ResearchA‐3252PetzenkirchenAustria
4. TU WienInstitute of Hydraulic Engineering and Water Resources ManagementKarlsplatz 13, A‐1040ViennaAustria