Green infrastructure or blue-green infrastructure refers to a network that provides the "ingredients" for solving urban and climatic challenges by building with nature.Hiltrud Pötz & Pierre Bleuze (2011). Urban green-blue grids for sustainable and dynamic cities. Delft: Coop for life. . The main components of this approach include stormwater management, climate adaptation, the reduction of heat stress, increasing biodiversity, food production, better air quality, sustainable energy production, clean water, and healthy soils, as well as more human centered functions, such as increased quality of life through recreation and the provision of 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. More recently scholars and activists have also called for green infrastructure that promotes social inclusion and equity rather than reinforcing pre-existing structures of unequal access to nature-based services.
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.
Introduction Green infrastructure
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".Benedict, Mark A. & McMahon, Edward T. (2006). Green Infrastructure: linking landscapes and communities Many such efforts take as their model prairies, where absorbent soil prevents runoff and vegetation filters out pollutants. Green infrastructure occurs at all scales. It is most often associated with green stormwater management systems, which are smart and cost-effective. However, green infrastructure acts as a supplemental component to other related concepts, and ultimately provides an ecological framework for social, economic, and environmental health of the surroundings.
Blue infrastructure "Blue infrastructure" refers to urban infrastructure relating to water. Blue infrastructure is commonly associated with green infrastructure in urban environments and may be referred to as "blue-green infrastructure" when being viewed 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. Coastal urban developments may also utilize pre-existing features of the coastline specifically employed in their design. Harbours, quays, piers, and other extensions of the urban environment are also often added to capture benefits associated with the marine environment. Blue infrastructure can support unique aquatic biodiversity in urban areas, including aquatic insects, amphibians, and water birds. There may considerable co-benefits to the health and wellbeing of populations with access to blue spaces in the urban context. Accessible blue infrastructure in urban areas is also referred as to blue spaces.
Terminology Ideas for green urban structures began in the 1870s with concepts of urban farming and garden allotments. Alternative terminology includes stormwater best management practices, 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 regulations for municipal separate storm sewer systems ("MS4") in 1990, requiring large MS4s to develop stormwater pollution prevention plans and implement "source control practices".EPA (1990-11-16). "National Pollutant Discharge Elimination System Permit Application Regulations for Storm Water Discharges". Federal Register, 44 FR 47990. EPA's 1993 handbook, Urban Runoff Pollution Prevention and Control Planning, identified best management practices to consider in such plans, including vegetative controls, filtration practices and infiltration practices (trenches, porous pavement). Regulations covering smaller municipalities were published in 1999.EPA (1999-12-08). "National Pollutant Discharge Elimination System—Regulations for Revision of the Water Pollution Control Program Addressing Storm Water Discharges." Federal Register, 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.The Conservation Fund, Arlington, VA. "Green Infrastructure." Accessed 2009-10-06.Maryland Department of Natural Resources, Annapolis, MD. Maryland's Green Infrastructure Assessment: A Comprehensive Strategy for Land Conservation and Restoration. May 2003. 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.
The term "green infrastructure" is sometimes expanded to "multifunctional" green infrastructure. Multifunctionality in this context refers to the integration and interaction of different functions or activities on the same piece of land.
The EPA extended the concept of "green infrastructure" to apply to the management of stormwater runoff at the local level through the use of natural systems, or engineered systems that mimic natural systems, to treat polluted runoff. This use of the term "green infrastructure" to refer to urban "green" best management practices contributes to the overall health of natural ecosystems, even though it is not central to the larger concept.
However, it is apparent that the term "blue-green infrastructure" is applied in an urban context and places a greater emphasis on the management of stormwater as an integral part of creating a sustainable, multifunctional urban environment. At the building level, the term "blue-green architecture" is used, which implements the same principles on a smaller scale. The focus here is on building greening with water management from alternative water resources such as grey water and rainwater.
History Green infrastructure as a term did not appear until the early 1990s, although ideas of green infrastructure had been used long before that. The first coined use of the term was seen in a 1994 report by Buddy MacKay, chair of the Florida Greenways Commission, to Florida governor Lawton Chiles about an infrastructure project undertaken in 1991: Florida Greenways Project. MacKay states, "Just as we carefully plan the infrastructure our communities need to support the people who live there—the roads, water and electricity—so must we begin to plan and manage Florida's green infrastructure".
Ancient China Chinese literary gardens are an example of a sustainable lawn that showcased natural beauty in suburban areas. These gardens, dating back to the Shang Dynasty (1600–1046 BC), were designed to allow native plant species to thrive in their natural conditions and appear untouched by humans. This created ecological havens within the city.
8th Century BC - 1st Century BC Greece was an early adopter of the concept of green Infrastructure with the invention of Greek agora. Agoras were meeting spaces that were built for social conversations and allowed Greeks to converse in public. Many were built across Greece, and some incorporated nature as a design aspect, giving nature a space among the public.
5th century - 15th century A common urban habitat, the lawn, consists of short grass and sometimes herbaceous plants. While modern artificial lawns have been connected to a negative environmental impact, lawns in the past have been more sustainable, and they promoted biodiversity and the growth of native plants. These historical lawns are impacting lawn design today to create more sustainable 'alternative lawns'.
In medieval Europe, lawns rich with flowers and herbaceous plants known as 'flower meads' are a good example of a more sustainable lawn. Since then, this idea has been used. In the Edwardian Era, lawns full of thyme, whose flowers attracted insects and pollinators, created biodiversity. A 20th century take on this lawn, the 'enamelled mead', has been used in England, and has the purpose of both aesthetics and for stormwater management.
During the height of the Renaissance, public areas became more common in new cities and infrastructure. These areas were carefully selected and would often be urban parks and gardens for the public to converse and relax at. Other than social uses, urban parks and gardens were used to improve the aesthetic of the urban environment they were present in. Urban spaces had environmental uses for the implementation of fresh air and reduced urban heating.
17th Century – 18th Century Green Infrastructure can be traced as far back as the 17th century in European society beginning in France. France used the presence of nature to provide social and spatial organization to their towns. Originally, nature in cities was used to provide social areas to interact, and plants were grown in these spaces to provide food in close proximity to the inhabitants. In this period, large open spaces were used to provide a calm setting that could give "sites of power with sites of sanctity" across France. These sites were used by the French elites to bring rural country town house beauty to their new urban houses in a showcase of power and elaborate display of wealth. The French implemented many different types of infrastructure throughout the 17th century that involved incorporating nature in some shape or form. Another example would be the use of promenades that were used by the French elites to flee the unhealthy living conditions of the cities and to avoid the filthy public areas available to the common folks. These areas were lush gardens that had a wide variety of vegetation and foliage that kept the air clean for the wealthy while allowing them to relax away from the poorer members of French society. Again, Mathis goes on to state, "The first cours [or promenades] were established in the capital at the instigation of Marie de Medici: the Mail de l'Arsenal (1604) and above all the Allée du Cours-la-Reine (1616), 1300 mètres long and lined with elms, running along the Seine, from the Tuileries Garden to the high ground of Chaillot," establishing the use of nature as a symbol of power and achievement amongst French royalty and the common people at the time.
Keeping and making cities green were at the forefront for city planners in France. They often incorporated design elements blending urbanism and nature, forming a relationship that showcased how the French grew alongside nature and often made it a key aspect of their expansion.