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Cities Can Have Health Promoting Park Systems Through Proximity, Accessibility, and Co-Location

The closer the park and the easier to get to, the more likely it will be used. Conversely, people who live far from parks are apt to utilize them less.

These obvious truths have implications for public health, but recognizing the problem does not automatically offer simple solutions for mayors, city councils, park directors, or urban planners. Creating new parks in a crowded, built-out city is a slow, arduous, and often expensive task. It can be done—it is being done in almost every city in the country—but it is not the only way to bring people and green space together. Much can be done outside the park fence, in the neighborhood, where the normal processes of urban construction, rehabilitation, and change occur at a faster pace.

Sometimes easiest to fix is the problem of accessibility. Some parks are underused simply because they are too hard to get to. Users may be blocked by steps, fences, walls, cliffs, railroad tracks, highways, waterways, or an unbroachable row of private residences. Some parks require a long jaunt to the other side just to gain entry. Others are literally visible from a home but unreachable by children without a chaperoned car ride.

Park access might be improved by constructing a ramp or pedestrian bridge in a key location, or by installing a traffic signal on a busy road. While such fixes might cost from $50,000 to several million dollars, that is a small price compared with what is routinely spent on highways and parking lots and would be more than offset by savings in health costs resulting from more frequent park use.

People are more likely to use parks that are close to places where they spend time: restaurants, shopping districts, libraries, gyms, and other meeting areas. In some cases parks can be sited close to such destinations. In other instances businesses and attractions can be allowed or encouraged to locate near existing parks. A mistaken Victorian sensibility sometimes holds that the “purity” of parks should not intersect with the “untidiness” of commercial areas. In fact, people like that proximity. They welcome the opportunity to buy picnic food or an ice cream cone to eat on a nearby park lawn or bench—and if that sojourn can be combined with a brisk walk, jog, or basketball game, so much the better.

Or, a large downtown destination park might be considered for a bike station, like the one offered at Chicago’s Millennium Park. There, for a membership fee, park users have access to one of 300 secure bike spaces along with lockers, showers, and a repair shop. For tourists, there are rental bikes. Completed in 2004 for $3.2 million, the facility today is so popular that it has a waiting list.

Best of all is the provision of plenty of housing near parks. This is an old concept with a new name: park-oriented development. From Lincoln Park in Chicago to Riverside Park in New York to Lake Harriet in Minneapolis, the parks surrounded by lots of people are the ones that can provide the greatest total amount of health benefits. But often U.S. cities are zoned so as to prevent that outcome. Some communities are averse to the look of taller buildings around parks; others may even think that the fewer people in the park, the better.

If denser development is not possible, park use can also be increased by improving accessibility through walking, bicycling, and public transit. (Automobile access is less desirable because it requires acres of parking and eliminates the health benefit of walking and cycling.) Ample park entrances, great sidewalks, and bike lanes on connecting streets; pedestrian-friendly perimeter roads with plenty of traffic signals and crosswalks; and easy grades and smooth trails for elderly and wheelchair-bound visitors: all these contribute to great access. In large parks, high-use destinations such as playgrounds, basketball courts, and swimming pools should be sited near the edge of the park, not deep in the interior.

"Catchment Circle." The area of a circle grows by the square of the radius. If a park is easy to reach by bicycle, 16 times as many people can get to it in the same amount of time it takes to walk from a mile away. Illustration: Helene Sherlock.

Bicycle access extends the “reach” of a park 16-fold over walking. This is because cycling is about four times faster than walking, and the “catchment circle”—the surrounding area from which park users can be drawn—increases by the square of the distance from the park (see diagram on right). Thus, improving bicycle access is an important way to get more people to the park (not to mention the health benefit from pedaling there and back).

Good public transit improves park access even more. It is no coincidence that eight of the ten most heavily used parks in American cities offer subway or light-rail access within one-quarter mile, and all of them have bus service that comes even closer. In New York City major parks almost invariably have subway service. Other parks well served by subway and rail include Boston Common, Forest Park in St. Louis, Millennium and Grant parks in Chicago, and the National Mall in Washington, D.C.

As new transit lines are built, it’s sometimes possible to align them with parks. Seattle’s new streetcar line terminates at 12-acre South Lake Union Park. The city is working to increase housing and commercial density in this near-downtown location, and the alignment of park and transit is particularly helpful in reaching the goal. “Especially at lunchtime,” says former Seattle Parks Foundation Director Karen Daubert, “you can see the crowds walking off the streetcar right into South Lake Union Park. It’s the perfect connection to this waterfront refuge.”

For larger parks, internal transit can also promote access. At 130-acre Washington Park in Portland, Oregon—home to the popular Rose and Japanese gardens—special Tri-Met buses not only connect to the nearest light-rail station but also make eight stops inside the park. The service is inexpensive (or free with a transfer), runs every 15 minutes, and is aggressively advertised by the park department, Tri-Met‚ and event promoters. The route gets about 500 riders per day on weekends and 420 on weekdays. From a health perspective, taking transit results in far more walking than accessing the park in a private automobile.

Here are a few examples of the ideas presented above:

Piedmont Park, Atlanta. Health-promoting park systems appreciate density. Credit: Ashley Szczepanski.

In recent years, Atlanta’s Piedmont Park has shown a marked growth in users. There are several reasons for this, including policies that have reduced auto traffic in the park, the rehabilitation of facilities, better signage‚ and additional programming. But also significant is the fact that more people now live in areas bordering or near the park. Unlike many other urban places, the Piedmont Park neighborhood is densifying, and the park itself is serving as a significant lure for development.

Between 2000 and 2009 alone, the City of Atlanta approved building permits for 16 new multi-unit rental and condominium apartment buildings within a half-mile of Piedmont Park, and the neighborhood gained nearly 100 single-family homes. All told, the park neighborhood gained 1,880 units, or about 4,500 people, over the decade. These people are the heaviest users of the park facilities. They compound their health benefit by often walking or running to the park rather than driving there.

“Piedmont Park is one of the single biggest assets we have in the neighborhood,” said Ginny Kennedy, director of urban design for the Midtown Alliance. “In everything we do, we encourage and try to reinforce access and visibility to the park.”

Perhaps most significant, the Midtown Alliance—whose goal is to make midtown Atlanta an “exceptional place to live, work, learn, shop, and play”—spearheaded the area’s 2001 rezoning. The changes enabled many more people to live and work near Piedmont Park and benefit from its health-promoting effects.

Midtown Greenway, Minneapolis. Health-promoting park systems locate parks and trails so as to benefit from other uses. Credit: Freewheel Bike Center.

Since its opening in 2000, Minneapolis’s Midtown Greenway has quickly become one of the best-used bike routes in the country, largely because it combines a park-like experience with true functionality. The mostly below-grade former rail line is quiet to ride, bordered with green, and unbroken by street intersections. Yet its almost six-mile length parallels a major commercial street only one block away, offering easy access to grocery and hardware stores, restaurants, video rentals‚ and pharmacies. “Fast, safe, and pleasant” is how Midtown Greenway Coalition Director Tim Springer describes the linear park—but it is also convenient. Instead of returning home from a bike ride and climbing into the car for errands, many Midtown Greenway users are able to multitask. The greenway leads them to their needs, and their needs lead them to the greenway.

The city has consciously helped. When a massive old Sears warehouse was converted into the Midtown Global Market, officials built a connection from the greenway and also landed a federal loan to create the Freewheel Bike Center‚ which provides storage, repair, rentals‚ and sales. Next door is a coffee shop. Nearby, the new Sheraton hotel has an outdoor patio overlooking the trail (and directs guests to rent bikes from Freewheel). The greenway also intersects with transit along the Hiawatha light-rail line, giving some Minneapolitans a car-free commute with morning and evening exercise to boot. All in all, the collocation of the park with diverse destinations has made this not only a greenway, but a “healthway.”

Want to know more ways urban park systems can best promote health and wellness?  Read this publication from The Trust for Public Land.

Urban Population Growth Creates New Demand for Parks

The Brookings Institution recently released a comprehensive report on metropolitan demographic changes over the past thirty years, which highlighted the increasing concentration of the U.S. population in major metropolitan areas.  Overall, metropolitan areas have grown consistently since 1980, and now over 80% of Americans live in metropolitan areas, i.e. cities and their suburbs.  Though suburban growth outpaced city growth between 2000 and 2010, all of the five fastest-growing metropolitan areas saw higher percentage growth in their urban cores.

Forecasts suggest cities will continue to grow over the next several decades, as empty-nesting baby-boomers retire to cities and the Millennials, who are known to prefer urban living, move into their first homes.

All of this is good news for city parks.  As American cities continue to grow, so will the demand for high-quality parkland accessible to urban neighborhoods.  Density creates park demand, and parks attract density.  Perhaps for these reasons, notable downtown residential growth in recent years has occurred in tandem with major investments in urban parks, from Cincinnati to Denver to Houston.

Central Park, New York
Credit: NYC.gov

While there are certain park functions for which density creates challenges, such as habitat preservation, park environments are largely improved by dense and diverse activity and use.  Urban observer and advocate Jane Jacobs was the first to suggest that parks are vacant spaces enlivened by the presence of urban activity.  Over the subsequent decades, the broader community of urbanists has continued to pursue this axiom, as well as its counterpart, that density requires the presence of open space. In his recent book, Walking Home, Ken Greenberg writes:

Greater density paradoxically goes hand in hand with the preservation of nature, giving urban dwellers easier access to the natural world than is the case for their suburban counterparts. Great urban parks like Central Park and Prospect Park in New York, the Bois de Boulogne in Paris, Chapultepec Park in Mexico City, and the Toronto Islands have historically been possible because of the larger populations nearby that have built and maintained them.

In addition to creating demand for parks, density also provides opportunities for parks to sustain themselves financially.  Park advocates and philanthropists, many of whom live or work near their parks, support park-friendly policies and contribute funding and volunteer hours. Dense activity also provides a market for fee-based park programs, from concessions to special events to carousels and skating rinks. These program elements in turn contribute to parks’ success, providing community amenities and reasons to travel to and linger in public space.

Residential density and open space have proved mutually supportive over time. Central Park and the growth of Manhattan are perhaps the best-known example of this trend.  Developed in the 1860s when the population of New York City was almost entirely concentrated downtown, the Central Park was located in public land (acquired through eminent domain) in a 3 by 47 block section of the City’s newly laid out grid.

The park’s designer, Frederick Law Olmsted, suggested that the residential development Central Park would attract would create enormous economic value to the city, creating a rationale for public investment. According to The Greatest Grid: The Master Plan of Manhattan 1811-2011:

Despite the lack of uptown residents, Olmsted anticipated that when the street grid eventually filled out, property near the park would increase in value, and he defended the park’s size on these grounds. When the construction of the grid was complete, Olmsted expected that an ‘artificial wall, twice as high as the Great Wall of China, composed of urban buildings’ would circle the park…

More recently, Santa Fe Railyard Park and Plaza was created in response to demand from the community to preserve the historic railyard site near the downtown core. Between 2000 and 2010, Santa Fe’s population grew by 8%, and this growth increased demand for open spaces for recreation and public gathering.

The Master Planning process for the site, which involved over 6,000 members of the local community, preserved 12 of the site’s 50 acres as a destination downtown park with an immensely popular farmers’ market. The remainder of the site was divided between cultural and community uses, commercial art galleries, office space, retail and restaurant venues, live-work units, and purely residential units. This vibrant mix of uses generates diverse activity and creates a natural constituency to support the new park.

Note: The Greatest Grid exhibit is on view at the Museum of the City of New York through July, 2012.

Creating and Financing Infill Parks in the Bay Area: Part I

San Francisco was just crowned the greenest city in the U.S. and Canada by one large study, a nod to its policies that require recycling, ban plastic shopping bags, and provide incentives for solar roofs.

But the Bay Area is also thinking of sustainability in terms of smarter growth throughout the region as a whole. The Association of Bay Area Governments (ABAG) has identified Priority Development Areas to encourage infill development, combining housing, amenities, and transit in a walkable environment.

These increasingly dense areas will need carefully planned parks. Some jurisdictions have done little more than hope for additional green space, while others have worked diligently but unsuccessfully to acquire parkland. Still others have succeeded in creating new parks but now have difficulty funding their maintenance.

To provide some guidance, The Trust for Public Land’s Center for City Park Excellence performed a study for ABAG, one component of which was identifying examples of how recently-completed infill parks were financed. We will be publishing each of the four case studies over the next several weeks. First up is Doyle Hollis Park in Emeryville.

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Tiny Emeryville, squeezed between Oakland, Berkeley and the Bay Bridge, has 10,000 residents and 20,000 daytime workers on only 1.2 square miles of land. For most of the 20th century it was an industrial center, famous for meatpacking plants and a Sherwin-Williams paint factory. It has since evolved into a hub for biotech and software companies, including Pixar Animation Studios, as well as a major shopping destination.

Emeryville has a dearth of parkland, particularly parkland away from San Francisco Bay, east of Interstate 80, since that highway is a significant physical and psychological barrier to the enjoyment of green space along the waterfront. The city also has a demand for auto parking because of the daily commuter influx. Doyle Hollis Park grew out of the competition between these two forces.

The park site was slated to become a parking structure. Credit: MIG, Inc. Courtesy Emeryville Planning and Building Department.

In 1999, when the city’s planning department began to develop the North Hollis Area Plan, situated in the transition zone from commercial to residential, it focused upon a warehouse in the block bounded by Doyle and Hollis Streets. In 2002, the warehouse site was slotted for a parking structure and steps were taken to relocate the tenant and arrange acquisition.

During this time, citizen opposition to the idea of a parking structure in the geographic heart of the North Hollis Area grew. The proposed six-story, 700-vehicle building abutted a low-density neighborhood and stood across from a middle school that lacked playing fields. It would have also shaded the new Emeryville Greenway and a pocket park.

“We first considered putting the garage beneath the park,” said Planner Diana Keena, “but the site is so narrow that just the entryway would have consumed a third of the space.” The city also considered building a smaller structure or allowing diagonal street parking around the perimeter of the park, but those, too, would have swallowed most of the park.

Neighbors, who had coalesced a few years earlier to redesign the greenway as a park rather than as a tree-lined auto-oriented street, arose again, voicing opposition to the parking structure, lobbying individual councilmembers, and gaining the support of the school board. “With persistence and a lot of hard work, we eventually convinced the City Council that a park — not a parking structure — was the right thing for the neighborhood,” recalls Jim Martin, one of the original leaders of Doyle Street Neighbors. The group ultimately convinced the City Council to rezone the block to open space.

Kids Playing at Doyle Hollis Park

Kids playing at Doyle Hollis Park. Credit: MIG, Inc. Courtesy Emeryville Planning and Building Department.

From then on, things moved relatively quickly. In 2005 the site, which had already been on the city’s acquisition list, was bought by the Emeryville Redevelopment Agency for $5.1 million, using capital improvement funds from a combination of tax revenue and bond proceeds. That same year, Economic Development Coordinator Ignacio Dayrit, now with the non-profit, San Francisco-based Center for Creative Land Recycling, secured a U.S. Environmental Protection Agency (EPA) brownfield assessment grant for Emeryville, $75,000 of which was applied to the Hollis Doyle parcel. (The site was found to have some petroleum contamination.) Also in 2005, Gates Associates was hired to do planning and community workshops for the park. Later, a $200,000 brownfield cleanup grant was used for site remediation, along with a $500,000 loan from the EPA’s Brownfield Revolving Fund, which was matched with $100,000 from the redevelopment agency. (The loan has since been repaid by the city.)

Design, construction, and remediation added up to $5.25 million, some of which was paid for through the city’s community development block grant program ($109,557), the California workforce housing benefits program ($37,000), and the StopWaste.org Bay-Friendly Landscaping program ($25,000). All told, $10.35 million was spent on the park. Day-to-day park maintenance is handled by the Emeryville Department of Public Works and costs approximately $53,000 a year.

Basketball court at Doyle Hollis Park, with fountain in foreground. Credit: MIG, Inc. Courtesy Emeryville Planning and Building Department.

Opened in 2009 after a year of construction, the 1.25-acre park includes a children’s play area, restrooms, a recreation lawn, a basketball court, a rain garden that processes 85 percent of stormwater runoff on-site, and a striking public art fountain designed by artist Masayuki Nagase. It opened “to great fanfare,” according to City Manager Pat O’Keefe, and Diana Keena remembers that eager children crawled under the construction fencing to play on the climbing structures before it was dedicated.  Since then, park use has exceeded all expectations. “During lunchtime on a sunny day the place is packed with workers, kids, and food vendors,” notes Jim Martin.

As for the existing parking concerns, the city is attempting to address them through transit improvements, including the free Emery-Go-Round shuttle that links downtown to the MacArthur BART station one mile away, partnering with developers in providing public parking components to private parking structures, and prodding employers to offer their workers free transit passes. Finally, Emeryville plans to install meters for all street parking to nudge more drivers into existing garages that traditionally have been underused. The efforts are already successful – recent statistics show that the single-occupancy-vehicle commuting rate of employees to Emeryville is only 36 percent, well below the East Bay average.

Pedestrians and Park Planning: How Far Will People Walk?

As cities vie to attract talented college graduates and sustain population growth, they are focusing attention on parks to increase livability and support a strong economy. Since parks must be convenient if they are to provide their benefits, many places have set goals for the maximum distance any resident should be from the nearest park. But the goals vary widely, from an eighth of a mile in Chicago to two miles in Atlanta. Many people wonder if it is even possible to establish a universal standard.

This is a complex question. An individual’s willingness to walk varies greatly depending on age, health, time availability, quality of surroundings, safety, climate, and many other factors. On top of the variability in walking patterns, a city’s density has a bearing on what is considered a reasonable distance and where it is cost effective to add new parks.

The majority of walking studies are for and about commuters. Broadly speaking, they indicate that most people are only willing to walk a quarter-mile as part of a commute. A New York Regional Plan Association study, for example, found that residents within a quarter-mile of a transit facility are 5 to 7 times more likely to walk to the station than other passengers.[1]

Credit: Lynn D. Rosentrater (Flickr Feed).

The quarter-mile standard is also supported by park equity research. Jennifer Wolch, now at the University of California at Berkeley, wrote in 2002 that a quarter-mile is reasonable “for parents taking toddlers and small children to a park for everyday outings and playground opportunities.”  In the context of Los Angeles, she noted, “trips of more than a quarter mile (especially in high-traffic areas or neighborhoods where parents have safety concerns) are unlikely to be acceptable to parents.”[2] 

Conversely, several studies show that a half-mile walk is well within a reasonable distance for most people. The 2002 National Survey of Bicyclist and Pedestrian Attitudes and Behavior, by the National Highway Traffic and Safety Administration and the Bureau of Transportation Statistics, surveyed almost 10,000 people over the age of 16 and found that only 5 percent of walking trips were for getting to work. [3] (This suggests that transit studies should not be too heavily relied upon to determine a reasonable distance to a park.) Of the other trips, 38 percent were for personal errands, 28 percent were for exercise, and 21 percent were for recreation or leisure. The average trip length was 1.3 miles.

A 1976 study of the Bay Area transit system found that only 50 percent of riders who walked to the facility came from within a six-minute walk, but 80 percent came from within ten minutes, or approximately a half-mile.[4] This data supports cities that set a standard of a half-mile (and in some cases, more) as a reasonable distance to walk to a park. Perhaps the crux of the issue is: do people consider walking to the park a chore, or is the walk part of the recreational experience itself?

This isn’t as funny as it sounds. A 1997 study from Austin, Texas stated that “utilitarian and recreational walk activities have been found to have distinct structural characteristics.…Walk distance and duration for commuting, shopping, and reaching transportation are shorter, and recreational walks for exercise, walking the dog, and socializing are longer.”[5] 

Transit-based studies also underscore people’s variability: most won’t walk much more than a quarter-mile to a bus stop, but most will walk up to a half-mile to a commuter rail station. Parks, too, draw pedestrians from “catchment areas” of various sizes, depending on their quality and amenities offered. In a 2002 article, Van Herzele and Weidemann note that “the maximum walking distance may differ according to the function a green space fulfils.”[6]

In summary, research supports the validity of both quarter-mile and half-mile distance goals, depending on perceptions of the built environment, safety, and time constraints. Of course, people’s preferences and habits are only part of the equation for planners, who must also take into account the cost effectiveness of expanding the park system versus improving current parks or focusing on connectivity.

Density is a major factor. Building a new park in a low-density area (5 units per acre) provides access to only about 1,500 people within a quarter-mile range.  In a very dense area (90 units per acre) it serves close to 30,000. So even if planners in, say, Charlotte found a reluctance to walk more than a quarter-mile to a park, the city still probably could not afford to build a park for every 1,500 residents.

The following table illustrates the total population within quarter-mile and half-mile buffers in areas of varying density:

Neighborhood Example

Density  (Units per Acre)

People per Acre (2.5 per Unit)

 Population in 1/4 mile buffer (126 acres)

Population in 1/2 mile buffer  (503 acres)

Residential near Charlotte, NC

5

12

1,570

6,283

Los Angeles or Emeryville, CA

10

25

3,141

12,566

Rowhouses in Capitol Hill, DC

20

50

6,283

25,132

High-rise complex in Detroit, MI

30

75

9,424

37,698

Standard block in Brooklyn, NY

60

150

18,849

75,397

Belltown high rises in Seattle, WA

90

225

28,273

113,096

Studies of walking patterns are critical for planners working to ensure an equitable distribution of parkland within a city. The dependence of people’s walking habits on the surrounding environment also suggest that cities could boost the utility of existing parks by increasing connectivity and making the process of reaching a park more pleasant.

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[1] Regional Plan Association (1997).  Building Transit-Friendly Communities: A Design and Development Strategy for the Tri-State Metropolitan Region (New York, New Jersey, Connecticut). 

[2] Wolch, J., Wilson, J., and Fehrenbach, J.  (2002).  Parks and Park Funding in Los Angeles: An Equity Mapping Analysis. University of Southern California Sustainable Cities Program. Retrieved from  http://dornsife.usc.edu/geography/ESPE/documents/publications_parks.pdf

[3] U.S. Department of Transportation’s National Highway Traffic Safety Administration and the Bureau of Transportation Statistics (2002).  National Survey of Pedestrian and Bicyclist Attitudes and Behaviors. Retrieved from  http://www.nhtsa.gov/DOT/NHTSA/Traffic%20Injury%20Control/Articles/Associated%20Files/810971.pdf

[4] California DOT (1979). BART’s First Five Years; Transportation and Travel Impacts (DOT-P-30-79-8).

[5] Shriver, K. (1997). Influence of Environmental Design on Pedestrian Travel Behavior in Four Austin Neighborhoods. Transportation Research Record 1578. Retrieved from  http://www.enhancements.org/download/trb/1578-09.PDF

[6] Van Herzele, A., and Weidemann, T. (2003).  A Monitoring Tool for the Provision of Accessible and Attractive Green Spaces. Landscape and Urban Planning 63, 109-126.

Of Parks, Podiums and Penumbras: How Density Changes Development

Cities that increase density by building skywards can inadvertently end up with impersonal streetscapes defined by monotonous walls of glass and concrete. Toronto has avoided the issue of dark, canyon-like streetscapes by mandating that buildings offer a human-scale street presence. Most large buildings are composed of a “podium” base, with towers receding from the street in steps as they grow upwards, allowing sunlight to filter through. But one developer, Brad Lamb, is tired of the monotonous wedding-cake aesthetic caused by codes that encourage “podiumism.”

He sees parks as a way to increase density without sacrificing beauty and creativity. This is a somewhat of a twist on the usual tension between density and open space, in which cities have to force developers to include parks as an offset to residential and commercial projects (in a future article, we’ll discuss Seattle’s Green Factor codes, which require new developments in dense areas to provide publicly accessible and visible landscaping).

In Toronto, Lamb wants to build a slender 47-story residential tower and replace the podium space of other towers with a tiny park (the entire lot is only 62 by 200 feet). The building is between two historic buildings and the park would feature a lawn, benches, and a fountain.

His plans, though, face some opposition from city planners. This is certainly not the first time that open space and density have struggled to coexist.

Justin Herman Plaza, San Francisco. Credit: Kenneth Lu (Flickr Feed)

San Francisco’s Proposition K, otherwise known as the Sunlight Ordinance, was the source of a recent clash between parks advocates and proponents of dense, transit-oriented city living. Passed in 1984, the ordinance bans the development of any building over forty feet that would cast a shadow on an existing park.

The Sunlight Ordinance halted the development of a group of residential towers, part of the high-profile remake of the Transbay Transit Center, when it was discovered that two of the towers would cast a shadow on nearby parks. The shadows would have fallen on St. Mary’s and Portsmouth Squares for an hour a day in the spring and fall, and on Justin Herman Plaza for an hour around lunchtime in the middle of winter.

The project, designed by Pelli Clarke Pelli Architects, eventually got the go-ahead, in part because developers agreed to pay $10 million for park improvements and to offset the impact of the shadows by building a 5.4-acre rooftop park over the transit center.  The park, which according to this video has the potential to match the grandeur of Chicago’s Millennium Park, will feature an open air amphitheatre, gardens, a trail for running and walking, open grass areas for picnics, lily ponds and more.

It will also provide significant environmental benefits by minimizing the heat island effect, regulating interior temperatures, and absorbing and filtering pollutants rising from the terminal, which will connect 11 regional transit systems and accommodate 100,000 passengers each day.

With more people yearning to move into cities, it is critical to ensure that densification and parks are mutually reinforcing. And in the end, there is no reason why they should not be: people in dense areas need nearby parks for health and relaxation, and parks benefit from a lively atmosphere that comes from being close to homes, shops, transit and workplaces. With the recent success of Chicago’s Millennium Park and New York’s High Line, cities such as Los Angeles , Seattle and San Diego are recognizing the potential of elevated parks to encourage density while also generating excitement and boosting livability.

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