InfoWorks ICM includes many of the latest modelling capabilities in the market and fully-distributed (FD) modelling is one of these abilities. Usually, urban stormwater models are semi-distributed (SD), i.e. are based on subcatchment units, where rainfall is applied and transformed into flow hydrographs that discharge to 1D nodes. FD models do not consider subcathments and apply the rainfall directly on surface elements of the 2D overland model. SD models have been applied in the water industry, but FD models can be more detailed and theoretically more realistic.
These two types of models were compared with two real case studies in the paper suggested below. The selected case studies have been investigated in the last recent years: Cranbrook catchment, London, UK; and Zona Central catchment, Coimbra, Portugal. The Cranbrook catchment has an area of 8.5 km2 and a flat topography, while the Zona Central is a very steep catchment with an area of 1.5 km2. In the Cranbrook catchment, modelling results were compared with monitoring data collected in the sewer network, and in the Zona Central catchment floodplains were analysed with photographic records of flooding events.
In general, FD models are more realistic and avoid simplifications and spatial data aggregation of SD models. The results suggest that FD models are more sensitive to the overland surface representation and require higher resolution of the sewer network data. In applications when high-resolution data are not available, the use of SD models could be a preferable choice. In the near future, FD models will benefit from the increase in data availability and their resolution, as well as data sources.
Read the entire article on the Water Journal website: http://www.mdpi.com/2073-4441/8/2/58