MODELING DRAINAGE PERFORMANCE IN AN INDIAN CATCHMENT

Surface-water flooding occurs frequently in low-income urban settlemen ts of developing countries, with impacts on public health and the loca l economy. In many locations, drainage systems are neither appropriate nor sustainable. A computer model of a small surface-water drainage c atchment has been developed within a slum improvement programme in Ind ore, India. The model was calibrated and verified against flow-survey data, and was used to study the effects on performance of maintenance (as reflected in solids build-up in pipes) and site grading. The resul ts confirm the critical importance of maintenance in drainage performa nce and the need for construction engineers to consider drainage caref ully before changing site-grading plans. The results also suggest some general trends in drainage performance during floods.