Keywords
bogota’s urban drainage, grey-box modelling, semi-distributed modelling, wastewater quality modelling
Start Date
1-7-2012 12:00 AM
Abstract
Models that represent the integrated urban drainage system are neededto holistically assess and manage its performance. Furthermore such modelsshould ideally be spatially distributed to support evaluation of individualcomponents and their role within the system. However, due to data constraints andcomputational costs, high resolution models of the sewer system are unlikely to beapplicable when dealing with large scale and complex systems. This workassesses the value of a relatively simple semi-distributed grey-box modellingapproach, which, in comparison with a fully distributed approach, decreasessupporting data requirements but still aims to provide a reasonable spatialrepresentation of the sewer system and its temporal variability, thus enablingintegrated assessment. New methods for characterising uncertainty in flow andpollution load inputs during dry weather conditions are also used. A large urbancatchment in Bogotá (Colombia) is used as a case study. Modelled and observedflow and pollutant concentration data demonstrated high apparently randomvariability of dry weather flow profiles within the sewer system. Against thisvariability, the effects of in-sewer processes were not identifiable except wherebackwaters caused particularly high retention times.
A semi-distributed modelling approach to support wastewater system management in large urban areas
Models that represent the integrated urban drainage system are neededto holistically assess and manage its performance. Furthermore such modelsshould ideally be spatially distributed to support evaluation of individualcomponents and their role within the system. However, due to data constraints andcomputational costs, high resolution models of the sewer system are unlikely to beapplicable when dealing with large scale and complex systems. This workassesses the value of a relatively simple semi-distributed grey-box modellingapproach, which, in comparison with a fully distributed approach, decreasessupporting data requirements but still aims to provide a reasonable spatialrepresentation of the sewer system and its temporal variability, thus enablingintegrated assessment. New methods for characterising uncertainty in flow andpollution load inputs during dry weather conditions are also used. A large urbancatchment in Bogotá (Colombia) is used as a case study. Modelled and observedflow and pollutant concentration data demonstrated high apparently randomvariability of dry weather flow profiles within the sewer system. Against thisvariability, the effects of in-sewer processes were not identifiable except wherebackwaters caused particularly high retention times.
