SEDIMENT MANAGEMENT IN URBAN DRAINAGE CATCHMENTS

Abstract

This report aims to provide a framework for managing sediment in the urban drainage catchment; 'sediment' is here defined as material that rainfall can wash into the drainage system. The report has eight specific objectives. It mainly emphasises: (1) above-ground processes; (2) cleaning practices (street sweeping and gully emptying): and (3) their interaction with the below-ground drainage system. It first addresses the potential problems associated with sediment, the characteristics and build-up of sediment, and the interaction between above-ground and below-ground phases. There is then a brief review of the legislation in England and Wales about cleaning, together with information on: (1) authorities and statutory responsibilities to perform cleaning; and (2) the published standards on which cleaning is based. The main techniques and equipment, currently used in cleaning processes, are described in detail. The development and findings of a simple catchment mathematical model are presented. Some recommendations are made for improvements to present practice, including a framework for managing sediment.