Integration of drainage, water quality and flood management in rural, urban and lowland areas

Abstract

Managing drainage in rural and peri-urban environments has become an essential part of integrated water management. Drainage has become a science of control, storage and (re)use while meeting triple bottom-line requirements (environment, social and economic assessments). Controlled drainage in rural settings aims at maintaining a groundwater table regime that will provide adequate rootzone aeration and soil salinity control but will not remove or use more water than necessary. In urban and peri-urban environments, the philosophy of water sensitive urban design (WSUD) aims at an integrated approach to urban water management through emphasising sensitivity to water in urban design. Urban landscape and architectural building elements now combine the areas of controlling flood flows, detention and treatment of stormwater and the reuse of stormwater as their principal functionalities. Constructed wetlands treat stormwater for recharge of aquifers and subsequent recovery for non-potable reuse. The increase in population, the urbanisation of rural and lowland (coastal-) areas, and the emergence of mega-cities together call for state-of-the-art drainage design as part of integrated water resources management at a river basin scale. This article describes the latest technological advances in drainage, flood management and water quality control