URBAN DRAINAGE SYSTEMS - DESIGN AND OPERATION

Design and operation of urban drainage systems are addressed in the co ntext of the urban water system comprising drainage, sewage treatment plants and receiving waters. The planning and design of storm sewers a re reviewed with reference to planning objectives, design objectives, flows and pollutant loads, sewer system structures and urban runoff co ntrol and treatment. The discussion of combined sewers focuses on hydr aulic design of combined sewer systems, including combined sewer overf low (CSO) structures, and the use of CSO structures and storage in con trol of CSOs. The section on operation of sewer systems focuses on rea l time control, its feasibility, planning, design, operation and appli cations. Sewer system planning and design are generally conducted usin g computer modelling tools and procedures which are reviewed in the la st section. A brief listing of selected models focuses on internationa lly used models. Finally, it was concluded that further improvements i n environmental and ecological protection of urban waters is feasible only by consideration of urban drainage systems in conjunctions with s ewage treatment and water quality in the receiving waters.