Sustainable drainage system
The central role of SuDS in blue-green infrastructure
Centuries of simplistic views on urban water management are slowly but inevitably being replaced by modern, sustainable methods – often centred around the blue-green infrastructure (BGI) approach. New methods are inevitable not least due to greater population densities and expanding impervious surfaces in urban areas, which intensify pressure on water drainage systems.
Sustainable urban drainage systems, abbreviated SuDS, are an integral part of the BGI approach to water management, aimed at making urban drainage systems compatible with the natural water cycle. SuDS may consist of "natural" measures, such as green roofs, planters or green belts – combined with "artificial" measures, such as underground infiltration, retention tanks and many other solutions.
Here, we will summarise a number of insights from the Sweco Urban Insight report "From threat to opportunity – revaluating storm water management in urban areas". As the name indicates, this report looks at the management of storm water in particular, and how value can be produced out of what once was merely a problem to be managed.
Background: Purpose and advantages of blue-green infrastructure
The blue-green infrastructure approach can perhaps best be summarised as building with nature, as opposed to only reacting to it, to solve urban challenges. It aims to secure a sustainable future while also generating multiple benefits in the environmental, ecological, social and cultural spheres.
It requires a coordinated interdisciplinary approach to water resource and green space management from institutional organisations, industry and academia, as well as local communities and stakeholders.
There are several terms and acronyms associated with this type of solution in various parts of the world, for example: Sustainable Drainage Systems (SuDS), Water-sensitive Urban Design (WSUD) in Australia, and Low impact Development (LID) or Best Management Practice (BMP) in the United States, as well as blue-green cities and blue-green infrastructure.
Some of the characteristics and benefits of this type of solution are:
- Pollution control, improved air and water quality
- Cost savings compared to operations and maintenance of traditional drainage systems
- Community amenities – attractive green areas, health and well-being benefits
- Improved habitats for wildlife
- Flood prevention and reduction
- Encouraging natural groundwater recharge
- Adaptation to climate change
- Innovative uses of SuDS in traffic management