related: from industrial wasteland to community park

many u.s. cities don’t offer equal access to green space. for example, los angeles has 23,000 acres of parks, which puts the city in the top 15 in terms of total green space, but much of this parkland is near the mountains so most of the city’s low-income, inner-city communities don’t have any parks at all. peter harnik, director of the center for city park excellence at the trust for public land, says in reality 3.8 million residents of l.a. are too far from “a park to use one easily, conveniently, or frequently.” similarly, in new york city, high-quality parkland is found in greater abundance in wealthier districts, while low-income communities don’t enjoy the same access. more than half of the city’s 59 community board districts were found to have less than 1.5 acres of parkland per 1,000 residents. a university of chicago study found that communities with lower incomes, higher poverty rates, and higher proportions of racial and ethnic minorities also had the “fewest opportunities for community-level physical activity.” lack of green space is then not just about unfairness, it’s about health. low-income communities may have higher rates of health problems like obesity and asthma in large part because they don’t have parks.
(source: “urban green: innovative parks for resurgent cities,” peter harnik, island press, 2010 and “healthy parks, healthy communities: addressing health disparities and park inequalities through public financing of playgrounds, and other physical activity settings,”
trust for public land, policy brief, november 2005)

new parks can sprout up in the unlikeliest places. low-income, inner-city communities are characterized by hardscapes – asphalt surfaces. when a community organizes and creates a plan for a new park, local governments can respond and purchase asphalt-covered areas like parking lots and transform them into public community parks. the average neighborhood park can run into the millions, but including a park budget in the initial master plan helps ensure local governments will finance it, and even partner with developers, local foundations, or conservancies to get it built. these types of projects can also come about if they are part of broader public-private urban redevelopment schemes aimed at providing housing, improving access to transit, and investing in the local environment. transportation infrastructure like boulevards, rail lines, and trails can be expanded, greened, and designed to become easily-accessible parks. in addition, even landfills, rooftops, reservoirs, and cemeteries can be turned into parks. (source:“urban green: innovative parks for resurgent cities,” peter harnik, island press, 2010)

park design needs to be compelling so people visit and forge community ties there. parks that are designed for local residents and include them in the design process often do the best. new york city’s famed central park, designed by asla founder frederick law olmsted, and bryant park, designed by laurie olin of fasla are two examples of great community parks designed for people. the 843-acre central park has many “functional areas,” including game fields, gardens, skating rinks, a boating lake, and winding paths that offer “dozens and dozens of different kinds and moments of experience “ says sarah goldhagen, architecture critic for the new republic. bryant park’s movable café table and chairs set under a rich tree canopy and spread around a central lawn enable people to easily form groups or stay on their own. the park is now viewed as a model for how public places can facilitate human interaction. human interaction isn’t just needed to make a popular and sustainable park, new research demonstrates that people with strong community ties also live longer healthier lives. parks provide the space for communities to form.
(source: “goldhagen: ‘democracies need physical spaces,” the dirt and “bowling alone,” robert putnam)

poor air quality has led to an explosion of asthma cases and other health problems among vulnerable populations including children, the elderly, and low-income residents. each year bad air causes two million deaths worldwide. also, in the u.s., there have been 8,000 premature deaths from excessive heat over the past 25 years. urban heat islands, which are caused, in part, by sunlight being absorbed by paved surfaces and roofs, lead to higher surface temperatures, up to 90 degrees. atmospheric air temperatures are also higher: in the day by up to 6 degrees, and at night, by up to 22 degrees. vulnerable populations also face greater risks of heat exhaustion. (source: world health organization (who) and heat island impacts, u.s. environmental protection agency (e.p.a.) )

increasing the tree canopy in cities is one way to fight both poor air quality and urban heat islands. research shows significant short-term improvements in air quality in urban areas with 100 percent tree cover. there, trees can reduce hourly ozone by up to 15 percent, sulfur dioxide by 14 percent, and particulate matter by 13 percent. u.s. trees remove some 784,000 tons of pollution annually, providing $3.8 billion in value. furthermore, a single large healthy tree can remove greater than 300 pounds of carbon dioxide from the atmosphere every year. in fact, new york city’s urban forest alone removes 154,000 tons of co2 annually. through their leaves, trees also provide evaporative cooling, which increases air humidity. shaded surfaces may be 20-45 degrees cooler, and evapotranspiration can reduce peak summer temperatures by 2-9 degrees. (source:“heat island mitigation: trees and vegetation, u.s. environmental protection agency (e.p.a.) and “sustaining america’s trees and forests,” david j. nowak, susan m. stein, paula b. randler, eric j. greenfield, sara j. comas, mary a. carr, and ralph j. alig, u.s. forest service. )

some other benefits: urban forests reduce energy use by providing shade in the summer and wind breaks in the winter, reduce stormwater runoff, remediate soils, and provide animal and plant habitat. trees have economic benefits: they increase property value. lastly, trees have positive cognitive effects and may even help improve moods. (source: “sustaining america’s trees and forests,” david j. nowak, susan m. stein, paula b. randler, eric j. greenfield, sara j. comas, mary a. carr, and ralph j. alig, u.s. forest service; “does looking at nature make people nicer?” the dirt blog and “the restorative effects of nature in cities,” the dirt blog)

according to the center for city park excellence at the trust for public land, almost half of all americans get less than the recommended amount of physical activity, and more than a third don’t get in any leisure-time physical activity at all. dr. richard jackson, former head of the centers for disease control’s national center for environmental health and now professor at ucla, adds that this overall lack of physical activity, along with americans’ taste for fatty, unhealthy foods, has helped turn obesity into a “common cause epidemic” in the u.s. furthermore, the cost of healthcare in the u.s., which now ranks as the most obese nation on earth, has reached 17 percent of gross domestic product (gdp). what’s the cause of this increasingly expensive health epidemic? – some answers can be found in the built environment. communities are often planned and built to enable constant car use, creating a “deep-rooted structural issue” impossible to remedy with medicines alone.
(source: center for city park excellence trust for public land and “dr. richard jackson: “we are no longer creating wellbeing,” the dirt, asla general session, october 2010 )

“designing for active living” is a new approach to community design that aims to design communities for all users, not just those driving in cars. even older communities are retrofitting infrastructure to provide multiple transportation options and easier access to outdoor activities, improving health in the process. designing for active living involves creating safe access to transit; “complete streets,” which offer wider sidewalks and bike lanes; bike share networks and stations; community trail networks; parks with exercise equipment; and community gardens — anything that gets people outdoors. in fact, new research demonstrates just being outside provides physical and mental health benefits. interacting with nature improves cognitive ability, provides a range of social benefits (like making people nicer), and shortens rehabilitation times among those recovering from illnesses. (source: “nature makes us more caring,” university of rochester, marc berman, marc, john jonides, and stephen kaplan, “the cognitive benefits of interacting with nature,” psychological science, volume 19, number 12, 2008 and “dr. richard jackson: “we are no longer creating wellbeing,” the dirt )

related: greensburg: a model to rebuild from catastrophes

traditional ways of constructing buildings create pollution and waste. building materials contain vast amounts of embedded energy. according to architecture 2030, building construction and materials account for 5.5 percent of global greenhouse gas emissions. in addition, while exact numbers aren’t available, trucks and cranes transporting and installing materials at construction sites produce considerable amounts of greenhouse gas emissions.
(source: architecture 2030)

typically, materials from torn-down buildings and sites are carted off to the landfill. the u.s. environmental protection agency says only 40 percent of building and construction material is now “recycled, reused, or sent to waste-to-energy facilities, while the remaining 60 percent of the materials is sent to landfills.” many sustainable architects, landscape architects, and construction firms are now moving towards a more sustainable construction process to reduce waste and greenhouse gas emissions. (source: environmental protection agency)

in a sustainable reconstruction, building materials are reused or recycled, dramatically reducing waste. for example, a new park can be created out of old building materials. once the materials have been separated, some are kept at the construction site and reprocessed. reclaimed soils, concrete rubble, glass, wood, and steel can be reused or recycled to serve new functions, reducing greenhouse gas emissions in the process. with climate change, any new construction methods that help landscape architects avoid producing additional emissions are a major benefit both to the project and society as a whole. in a sustainable landscape, everything old is made new again. (source: reuse alliance)

according to a report from the sustainable business network of greater philadelphia, one inch of rainwater hitting one acre of asphalt over an hour yields 27,000 gallons of water. in many communities, this water flows into combined stormwater / sewer systems, which channel both sewage and rainwater together through underground pipes to central treatment facilities. storms can quickly overrun these combined systems, leading to flooding with pollutant-laden water and even backed up sewage. in fact, in many older cities like philadelphia, basements can flood with excrement during major storms, creating major public health issues in the process. (source: grey to green: jumpstarting private investment in green stormwater infrastructure)

the term “green infrastructure” is used to describe how networks of natural ecosystems also function as crucial community infrastructure, providing ecosystem services and improving environmental sustainability. in the context of managing stormwater, green infrastructure can be defined as man-made systems that mimic natural approaches. green roofs, bioswales, bioretention ponds, and permeable pavements are a few key examples of local green infrastructure, and all work by turning hard asphalt surfaces into green, absorbent ones. for example, green roofs can retain 40-60 percent of stormwater hitting rooftops. bioswales and retention ponds can absorb water and channel or hold excess runoff, cleansing pollutants in the process. however, even just adding extra trees, which consume lots of water, can help. evergreens and conifers were found to intercept 35 percent of water hitting them. (source: u.s. environmental protection agency)

adding in green infrastructure systems is not only good for managing water, but also good for communities. green infrastructure can lower air temperatures, which is crucial in cities facing the urban heat island effect. green roofs can double-up as roof-top parks, farms, and natural habitats for wildlife, providing a range of benefits. chicago alone has seven million square feet of green roofs, which are often filled with native plants. for communities facing tight budgets, green infrastructure systems are also the most cost-effective way to manage storm water when compared with rebuilding crumbling underground pipes. philadelphia, which charges homeowners and local companies for their runoff, is now considering $1.6 billion plan to use natural systems to alleviate its major stormwater management problems. (source: the vancouver sun, grey to green: jumpstarting private investment in green stormwater infrastructure)