Stormwater is an issue in urban areas, because of the amount of development in terms of building work and man-made structures and surfaces. Due to the nature of the materials used in this construction process, water tends not to be able to soak away into the ground as concrete and tarmac tend to be impermeable.

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This results in the need for drainage and sewers, which need to be carefully managed and maintained in order to prevent these overflowing at times of heavy rain. Stormwater management also involves the taking of preventative and precautionary measures to avoid pollution or flooding damage from stormwater and excess surface runoff.

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Stormwater has a number of potential negative effects on the environment. It can cause erosion to natural waterways, transfer pollutants into the water system and the rivers and in the worst cases cases it can cause damage by flooding. Therefore it is now a vital part of the design process to take the potential risks of stormwater into account when undertaking any urban planning.