Blue-Green Cities

Green infrastructure or blue-green infrastructure is a network providing the “ingredients” for solving urban and climatic challenges by building with nature. The main components of this approach include stormwater management, climate adaptation, less heat stress, more biodiversity, food production, better air quality, sustainable energy production, clean water and healthy soils, as well as the more anthropocentric functions such as increased quality of life through recreation and providing shade and shelter in and around towns and cities. Green infrastructure also serves to provide an ecological framework for social, economic and environmental health of the surroundings. Green Infrastructure is considered a subset of Sustainable and Resilient Infrastructure, which is defined in standards such as SuRe - the Standard for Sustainable and Resilient Infrastructure. However, green infrastructure can also mean 'low-carbon infrastructure' such as renewable energy infrastructure and public transportation systems (See 'low-carbon infrastructure'). Blue-green infrastructure can also be a component of 'sustainable drainage systems' or 'sustainable urban drainage systems' (SuDS or SUDS) designed to manage water quantity and quality, while providing improvements to biodiversity and amenity. Green infrastructure or blue-green infrastructure is a network providing the “ingredients” for solving urban and climatic challenges by building with nature. The main components of this approach include stormwater management, climate adaptation, less heat stress, more biodiversity, food production, better air quality, sustainable energy production, clean water and healthy soils, as well as the more anthropocentric functions such as increased quality of life through recreation and providing shade and shelter in and around towns and cities. Green infrastructure also serves to provide an ecological framework for social, economic and environmental health of the surroundings. Green Infrastructure is considered a subset of Sustainable and Resilient Infrastructure, which is defined in standards such as SuRe - the Standard for Sustainable and Resilient Infrastructure. However, green infrastructure can also mean 'low-carbon infrastructure' such as renewable energy infrastructure and public transportation systems (See 'low-carbon infrastructure'). Blue-green infrastructure can also be a component of 'sustainable drainage systems' or 'sustainable urban drainage systems' (SuDS or SUDS) designed to manage water quantity and quality, while providing improvements to biodiversity and amenity. Nature can be used to provide important services for communities by protecting them against flooding or excessive heat, or helping to improve air, soil and water quality. When nature is harnessed by people and used as an infrastructural system it is called “green infrastructure”. Green infrastructure occurs at all scales. It is most often associated with stormwater management systems, which are smart and cost-effective. However, green infrastructure is really a larger concept and is closely associated with many other things. Green infrastructure also serves to provide an ecological framework for social, economic and environmental health of the surroundings. 'Blue infrastructure' refers to urban infrastructure relating to water. Blue infrastructure is commonly associated with green infrastructure in the urban setting and may be referred to as 'blue-green' infrastructure when in combination. Rivers, streams, ponds and lakes may exist as natural features within cities, or be added to an urban environment as an aspect of its design. Urban developments on coasts may also have pre-existing features of the coastline specifically employed in their design. Harbours, quays, piers and other extensions of the urban environment may also be added to capture benefits associated with the marine environment. There may considerable co-benefits to health and wellbeing of populations with access to blue spaces in the urban context. Some people might expect that green spaces are excessive to maintain and extravagant in nature, but high-performing green spaces can provide real economic, ecological and social benefits. For example: In result, high performing green spaces work to create a balance between built and natural environments. A study in 2012 that focused on 479 green infrastructure projects across the United States, found that 44% of green infrastructure projects reduced costs compared to the 31% that increased the costs. The most notable cost savings were due to reduced stormwater runoff and decreased heating and cooling costs. Ideas for green urban structures began in the 1870s with concepts of urban farming and garden allotments. Alternative terminology includes stormwater best management practices (BMPs), source controls, and low impact development (LID) practices. Green infrastructure concepts originated in mid-1980s proposals for best management practices that would achieve more holistic stormwater quantity management goals for runoff volume reduction, erosion prevention, and aquifer recharge. In 1987, amendments to the U.S. Clean Water Act introduced new provisions for management of diffuse pollutant sources from urban land uses, establishing the regulatory need for practices that unlike conventional drainage infrastructure managed runoff 'at source.' The U.S. Environmental Protection Agency (EPA) published its initial MS4 regulations in 1990, requiring large MS4s to develop stormwater pollution prevention plans and implement 'source control practices'. EPA's 1993 handbook, Urban Runoff Pollution Prevention and Control Planning, identified BMPs to consider in such plans, including vegetative controls, filtration practices and infiltration practices (trenches, porous pavement). Regulations covering smaller municipalities were published in 1999. MS4s serve over 80% of the US population and provide drainage for 4% of the land area. Green infrastructure is a concept that highlights the importance of the natural environment in decisions about land-use planning. However, the term does not have a widely recognized definition. Also known as “blue-green infrastructure”, or “green-blue urban grids” the terms are used by many design-, conservation- and planning-related disciplines and commonly feature stormwater management, climate adaptation and multifunctional green space.