Green infrastructure
Encyclopedia
Green Infrastructure is a concept originating in the United States
in the mid-1990s that highlights the importance of the natural environment in decisions about land use planning
. In particular there is an emphasis on the "life support" functions provided by a network of natural ecosystem
s, with an emphasis on interconnectivity
to support long-term sustainability
. Examples include clean water
and healthy soils, as well as the more anthropocentric
functions such as recreation
and providing shade and shelter in and around towns and cities.
The United States Environmental Protection Agency (EPA) has extended the concept 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 (BMPs), although not central to the larger concept, does contribute to the overall health of natural ecosystems.
in a way that highlights its function and subsequently seeks to put in place, through regulatory
or planning policy, mechanisms that safeguard critical natural areas. Where life support functions are found to be lacking, plans may propose how these can be put in place through landscaped
and/or engineered
improvements. 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. This is key to the efficient and sustainable
use of land, especially in a compact and bustling country like England
where pressures on land are particularly acute. An example might be an urban edge river flood plain which provides a repository for flood waters, acts as a nature reserve
, provides a recreational green space
and could also be productively farmed (probably through grazing). There is growing evidence that the natural environment also has a positive effect on human health
, Green Infrastructure planning is increasingly recognised as a valuable approach for spatial planning
and is now seen in national, regional
and local planning
and policy documents and strategies, for example in the Milton Keynes
and South Midlands
Growth area.
In 2009, guidance on green infrastructure planning was published by Natural England, and can be accessed online at http://www.naturalengland.org.uk/ourwork/planningtransportlocalgov/greeninfrastructure/default.aspx. This guidance promotes the importance of green infrastructure in 'place-making', i.e. in recognising and maintaining the character of a particular location, especially where new development is planned.
In North West England
the former Regional Spatial Strategy had a specific Green Infrastructure Policy (EM3 - Green Infrastructure) as well as other references to the concept in other land use development policies (e.g. DP6). The policy was supported by the North West Green Infrastructure Guide. The Green Infrastructure Think Tank (GrITT) provides the support for policy development in the region and manages the web site that acts as a repository for information on Green Infrastructure.
The Natural Economy Northwest programme has supported a number of projects, commissioned by The Mersey Forest to develop the evidence base for green infrastructure in the region. In particular it has work has been undertaken to look at the economic value of green infrastructure, the linkage between grey and green infrastructure and also to identify areas where green infrastructure may play critical role in helping to overcome issues such as risks of flood or poor air quality.
In March 2011, a prototype Green Infrastructure Valuation Toolkit was launched. The Toolkit is available under a Creative Commons licence, and provides a range of tools that provide economic valuation of green infrastructure interventions. The toolkit has been trialled in a number of areas and strategies, including the Liverpool Green Infrastructure Strategy.
Green Infrastructure is being promoted as an effective and efficient response to projected climate change.
generally through more extensive management of stormwater runoff. The practices are expected to reduce stress on traditional water drainage
infrastructure--storm sewers and combined sewers--which are typically extensive networks of underground pipes
and/or surface water channels in U.S. cities, towns and suburban areas. Improved stormwater management is expected to reduce the frequency of combined sewer overflow
s and sanitary sewer overflow
s, and provide other environmental benefits.
For example, the City of Philadelphia has installed or supported a variety of retrofit projects in neighborhoods throughout the city. Installed improvements include:
Some of these facilities reduce the volume of runoff entering the city's aging combined sewer system, and thereby reduce the extent of system overflows during rainstorms.
Another US example, the State of Maryland
, has promoted a program called GreenPrint. GreenPrint Maryland is a first in the nation web-enabled map showing the relative ecological importance of every parcel of land in the State.
Combining color-coded maps, information layers, and aerial photography
with public openness and transparency, Greenprint Maryland applies the best environmental science and Geographic Information Systems (GIS) to the urgent work of preserving and protecting environmentally critical lands. A valuable new tool not only for making land conservation decisions today, but for building a broader and better informed public consensus for sustainable growth and land preservation decisions into the future.
The program was established in 2001 with the objective to “preserve an extensive, intertwined network of land vital to long term survival of our native plants and wildlife and industries dependent on clean environment and abundant natural resources.”
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
in the mid-1990s that highlights the importance of the natural environment in decisions about land use planning
Land use planning
Land-use planning is the term used for a branch of public policy encompassing various disciplines which seek to order and regulate land use in an efficient and ethical way, thus preventing land-use conflicts. Governments use land-use planning to manage the development of land within their...
. In particular there is an emphasis on the "life support" functions provided by a network of natural ecosystem
Ecosystem
An ecosystem is a biological environment consisting of all the organisms living in a particular area, as well as all the nonliving , physical components of the environment with which the organisms interact, such as air, soil, water and sunlight....
s, with an emphasis on interconnectivity
Interconnectivity
Interconnectivity is a concept that is used in numerous fields such as cybernetics, biology, ecology, network theory, and non-linear dynamics. The concept can be summarized as that all parts of a system interact with and rely on one another simply by the fact that they occupy the same system, and...
to support long-term sustainability
Sustainability
Sustainability is the capacity to endure. For humans, sustainability is the long-term maintenance of well being, which has environmental, economic, and social dimensions, and encompasses the concept of union, an interdependent relationship and mutual responsible position with all living and non...
. Examples include clean water
Water
Water is a chemical substance with the chemical formula H2O. A water molecule contains one oxygen and two hydrogen atoms connected by covalent bonds. Water is a liquid at ambient conditions, but it often co-exists on Earth with its solid state, ice, and gaseous state . Water also exists in a...
and healthy soils, as well as the more anthropocentric
Anthropocentrism
Anthropocentrism describes the tendency for human beings to regard themselves as the central and most significant entities in the universe, or the assessment of reality through an exclusively human perspective....
functions such as recreation
Recreation
Recreation is an activity of leisure, leisure being discretionary time. The "need to do something for recreation" is an essential element of human biology and psychology. Recreational activities are often done for enjoyment, amusement, or pleasure and are considered to be "fun"...
and providing shade and shelter in and around towns and cities.
The United States Environmental Protection Agency (EPA) has extended the concept to apply to the management of stormwater
Stormwater
Stormwater is water that originates during precipitation events. It may also be used to apply to water that originates with snowmelt that enters the stormwater system...
runoff at the local level through the use of natural systems, or engineered systems that mimic natural systems, to treat polluted runoff
Urban runoff
Urban runoff is surface runoff of rainwater created by urbanization. This runoff is a major source of water pollution in many parts of the United States and other urban communities worldwide.-Overview:...
. This use of the term "green infrastructure" to refer to urban "green" best management practices (BMPs), although not central to the larger concept, does contribute to the overall health of natural ecosystems.
Planning approach
The Green Infrastructure approach analyses the natural environmentNatural environment
The natural environment encompasses all living and non-living things occurring naturally on Earth or some region thereof. It is an environment that encompasses the interaction of all living species....
in a way that highlights its function and subsequently seeks to put in place, through regulatory
Regulation
Regulation is administrative legislation that constitutes or constrains rights and allocates responsibilities. It can be distinguished from primary legislation on the one hand and judge-made law on the other...
or planning policy, mechanisms that safeguard critical natural areas. Where life support functions are found to be lacking, plans may propose how these can be put in place through landscaped
Landscaping
Landscaping refers to any activity that modifies the visible features of an area of land, including:# living elements, such as flora or fauna; or what is commonly referred to as gardening, the art and craft of growing plants with a goal of creating a beautiful environment within the landscape.#...
and/or engineered
Environmental engineering
Environmental engineering is the application of science and engineering principles to improve the natural environment , to provide healthy water, air, and land for human habitation and for other organisms, and to remediate polluted sites...
improvements. 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. This is key to the efficient and sustainable
Sustainability
Sustainability is the capacity to endure. For humans, sustainability is the long-term maintenance of well being, which has environmental, economic, and social dimensions, and encompasses the concept of union, an interdependent relationship and mutual responsible position with all living and non...
use of land, especially in a compact and bustling country like England
England
England is a country that is part of the United Kingdom. It shares land borders with Scotland to the north and Wales to the west; the Irish Sea is to the north west, the Celtic Sea to the south west, with the North Sea to the east and the English Channel to the south separating it from continental...
where pressures on land are particularly acute. An example might be an urban edge river flood plain which provides a repository for flood waters, acts as a nature reserve
Nature reserve
A nature reserve is a protected area of importance for wildlife, flora, fauna or features of geological or other special interest, which is reserved and managed for conservation and to provide special opportunities for study or research...
, provides a recreational green space
Open space reserve
Open space reserve, open space preserve, and open space reservation, are planning and conservation ethics terms used to describe areas of protected or conserved land or water on which development is indefinitely set aside...
and could also be productively farmed (probably through grazing). There is growing evidence that the natural environment also has a positive effect on human health
UK applications
In the United KingdomUnited Kingdom
The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...
, Green Infrastructure planning is increasingly recognised as a valuable approach for spatial planning
Spatial planning
Spatial planning refers to the methods used by the public sector to influence the distribution of people and activities in spaces of various scales. Discrete professional disciplines which involve spatial planning include land use planning, urban planning, regional planning, transport planning and...
and is now seen in national, regional
Regional planning
Regional planning deals with the efficient placement of land use activities, infrastructure, and settlement growth across a larger area of land than an individual city or town. The related field of urban planning deals with the specific issues of city planning...
and local planning
Urban planning
Urban planning incorporates areas such as economics, design, ecology, sociology, geography, law, political science, and statistics to guide and ensure the orderly development of settlements and communities....
and policy documents and strategies, for example in the Milton Keynes
Milton Keynes
Milton Keynes , sometimes abbreviated MK, is a large town in Buckinghamshire, in the south east of England, about north-west of London. It is the administrative centre of the Borough of Milton Keynes...
and South Midlands
South Midlands
The South Midlands is a notional area of England. According to one definition, it is the southern portion of the East Midlands together with the northern portion of South East England and the western portion of the East of England, and just as there is no agreed definition for these areas,...
Growth area.
In 2009, guidance on green infrastructure planning was published by Natural England, and can be accessed online at http://www.naturalengland.org.uk/ourwork/planningtransportlocalgov/greeninfrastructure/default.aspx. This guidance promotes the importance of green infrastructure in 'place-making', i.e. in recognising and maintaining the character of a particular location, especially where new development is planned.
In North West England
North West England
North West England, informally known as The North West, is one of the nine official regions of England.North West England had a 2006 estimated population of 6,853,201 the third most populated region after London and the South East...
the former Regional Spatial Strategy had a specific Green Infrastructure Policy (EM3 - Green Infrastructure) as well as other references to the concept in other land use development policies (e.g. DP6). The policy was supported by the North West Green Infrastructure Guide. The Green Infrastructure Think Tank (GrITT) provides the support for policy development in the region and manages the web site that acts as a repository for information on Green Infrastructure.
The Natural Economy Northwest programme has supported a number of projects, commissioned by The Mersey Forest to develop the evidence base for green infrastructure in the region. In particular it has work has been undertaken to look at the economic value of green infrastructure, the linkage between grey and green infrastructure and also to identify areas where green infrastructure may play critical role in helping to overcome issues such as risks of flood or poor air quality.
In March 2011, a prototype Green Infrastructure Valuation Toolkit was launched. The Toolkit is available under a Creative Commons licence, and provides a range of tools that provide economic valuation of green infrastructure interventions. The toolkit has been trialled in a number of areas and strategies, including the Liverpool Green Infrastructure Strategy.
Green Infrastructure is being promoted as an effective and efficient response to projected climate change.
US applications
Green infrastructure programs managed by EPA and partner organizations are intended to improve water qualityWater quality
Water quality is the physical, chemical and biological characteristics of water. It is a measure of the condition of water relative to the requirements of one or more biotic species and or to any human need or purpose. It is most frequently used by reference to a set of standards against which...
generally through more extensive management of stormwater runoff. The practices are expected to reduce stress on traditional water drainage
Drainage
Drainage is the natural or artificial removal of surface and sub-surface water from an area. Many agricultural soils need drainage to improve production or to manage water supplies.-Early history:...
infrastructure--storm sewers and combined sewers--which are typically extensive networks of underground pipes
Pipe (material)
A pipe is a tubular section or hollow cylinder, usually but not necessarily of circular cross-section, used mainly to convey substances which can flow — liquids and gases , slurries, powders, masses of small solids...
and/or surface water channels in U.S. cities, towns and suburban areas. Improved stormwater management is expected to reduce the frequency of combined sewer overflow
Combined sewer overflow
A combined sewer is a type of sewer system that collects sanitary sewage and stormwater runoff in a single pipe system. Combined sewers can cause serious water pollution problems due to combined sewer overflows, which are caused by large variations in flow between dry and wet weather...
s and sanitary sewer overflow
Sanitary sewer overflow
Sanitary sewer overflow is a condition whereby untreated sewage is discharged into the environment prior to reaching treatment facilities thereby escaping wastewater treatment. When caused by rainfall it is also known as wet weather overflow. It is primarily meaningful in developed countries,...
s, and provide other environmental benefits.
For example, the City of Philadelphia has installed or supported a variety of retrofit projects in neighborhoods throughout the city. Installed improvements include:
- permeable pavements in parks, basketball courts and parking lots
- rain gardenRain gardenA rain garden is a planted depression that allows rainwater runoff from impervious urban areas like roofs, driveways, walkways, parking lots, and compacted lawn areas the opportunity to be absorbed...
s and bioretentionBioretentionBioretention is the process in which contaminants and sedimentation are removed from stormwater runoff. Stormwater is collected into the treatment area which consists of a grass buffer strip, sand bed, ponding area, organic layer or mulch layer, planting soil, and plants...
systems at schools and other public facilities - constructed wetlandConstructed wetlandA constructed wetland or wetpark is an artificial wetland, marsh or swamp created as a new or restored habitat for native and migratory wildlife, for anthropogenic discharge such as wastewater, stormwater runoff, or sewage treatment, for land reclamation after mining, refineries, or other...
s for management of stormwater runoff.
Some of these facilities reduce the volume of runoff entering the city's aging combined sewer system, and thereby reduce the extent of system overflows during rainstorms.
Another US example, the State of Maryland
Maryland
Maryland is a U.S. state located in the Mid Atlantic region of the United States, bordering Virginia, West Virginia, and the District of Columbia to its south and west; Pennsylvania to its north; and Delaware to its east...
, has promoted a program called GreenPrint. GreenPrint Maryland is a first in the nation web-enabled map showing the relative ecological importance of every parcel of land in the State.
Combining color-coded maps, information layers, and aerial photography
Aerial photography
Aerial photography is the taking of photographs of the ground from an elevated position. The term usually refers to images in which the camera is not supported by a ground-based structure. Cameras may be hand held or mounted, and photographs may be taken by a photographer, triggered remotely or...
with public openness and transparency, Greenprint Maryland applies the best environmental science and Geographic Information Systems (GIS) to the urgent work of preserving and protecting environmentally critical lands. A valuable new tool not only for making land conservation decisions today, but for building a broader and better informed public consensus for sustainable growth and land preservation decisions into the future.
The program was established in 2001 with the objective to “preserve an extensive, intertwined network of land vital to long term survival of our native plants and wildlife and industries dependent on clean environment and abundant natural resources.”
GIS applications
The continued development of Geographic Information Systems (GIS) and their increasing level of use is particularly important in the development of Green Infrastructure plans. The plans frequently are based on GIS anaysis of many layers of geographic information.See also
- InfrastructureInfrastructureInfrastructure is basic physical and organizational structures needed for the operation of a society or enterprise, or the services and facilities necessary for an economy to function...
- Low impact developmentLow impact developmentLow-impact development is a term used in the United States to describe a land planning and engineering design approach to managing stormwater runoff. LID emphasizes conservation and use of on-site natural features to protect water quality...
- Sustainable urban drainage systemsSustainable urban drainage systemsSustainable Drainage Systems , sometimes known as Sustainable Urban Drainage Systems , are designed to reduce the potential impact of new and existing developments with respect to surface water drainage discharges.-Background:...
- Urban runoffUrban runoffUrban runoff is surface runoff of rainwater created by urbanization. This runoff is a major source of water pollution in many parts of the United States and other urban communities worldwide.-Overview:...
- Watershed centralWatershed CentralWatershed Central is an Environmental Protection Agency website developed to organize information and tools relevant to watershed management from across the country....
Further reading
- EPA. "Managing Wet Weather with Green Infrastructure"
- EPA. "Municipal Handbook: multiple pdf documents available for download"
- City of Philadelphia (2009) "Green City Clean Waters"
- City of Nashville & Davidson County (2009) "Green Infrastructure Design"
- City of Chicago (2010) "Green Alley Handbook"
- SETDD (2011). "Green Infrastructure Handbook"
- Center for Green Infrastructure Design (2011). "Why is Green Infrastructure Important ?"
- Center for Green Infrastructure Design (2011). "The Benefits of Green Infrastructure"
External links
- Green Infrastructure Case Studies The Conservation Fund
- Maryland's Green Infrastructure- Maryland Department of Natural Resources
- Sonoran Desert Conservation Plan - Pima County, ArizonaPima County, Arizona-2010:Whereas according to the 2010 U.S. Census Bureau:*74.3% White*3.5% Black*3.3% Native American*2.6% Asian*0.2% Native Hawaiian or Pacific Islander*3.7% Two or more races*12.4% Other races*34.6% Hispanic or Latino -2000:...
- The Center for Green Infrastructure Design - The Center for Green Infrastructure Design
- Green Infrastructure Wiki
- Low Impact Development - The Low Impact Development Center
- Green Infrastructure Resource Center - American Society of Landscape Architects