Modeling of facade leaching in urban catchments
Article first published online: 6 DEC 2012
©2012. American Geophysical Union. All Rights Reserved.
Water Resources Research
Volume 48, Issue 12, December 2012
How to Cite
2012), Modeling of facade leaching in urban catchments, Water Resour. Res., 48, W12503, doi:10.1029/2012WR012359., , , and (
- Issue published online: 6 DEC 2012
- Article first published online: 6 DEC 2012
- Manuscript Accepted: 24 OCT 2012
- Manuscript Revised: 30 AUG 2012
- Manuscript Received: 8 MAY 2012
 Building facades are protected from microbial attack by incorporation of biocides within them. Flow over facades leaches these biocides and transports them to the urban environment. A parsimonious water quantity/quality model applicable for engineered urban watersheds was developed to compute biocide release from facades and their transport at the urban basin scale. The model couples two lumped submodels applicable at the basin scale, and a local model of biocide leaching at the facade scale. For the facade leaching, an existing model applicable at the individual wall scale was utilized. The two lumped models describe urban hydrodynamics and leachate transport. The integrated model allows prediction of biocide concentrations in urban rivers. It was applied to a 15 km2urban hydrosystem in western Switzerland, the Vuachère river basin, to study three facade biocides (terbutryn, carbendazim, diuron). The water quality simulated by the model matched well most of the pollutographs at the outlet of the Vuachère watershed. The model was then used to estimate possible ecotoxicological impacts of facade leachates. To this end, exceedance probabilities and cumulative pollutant loads from the catchment were estimated. Results showed that the considered biocides rarely exceeded the relevant predicted no-effect concentrations for the riverine system. Despite the heterogeneities and complexity of (engineered) urban catchments, the model application demonstrated that a computationally “light” model can be employed to simulate the hydrograph and pollutograph response within them. It thus allows catchment-scale assessment of the potential ecotoxicological impact of biocides on receiving waters.