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Benefitting From a Cover Up: How Concealing Urban Highways Can Create Parkland

A twelfth excerpt from the recently released book published by Island Press called Urban Green: Innovative Parks for Resurgent Cities. In this post, we look at some cities who have created parkland by concealing or burying highways.

Urban radicals want automobiles banned. Urban moderates can perhaps live with cars as long as they’re neither seen nor heard.

In European central cities the radicals have the upper hand. U.S. cities are increasingly settling for a compromise–an expensive compromise–by putting freeway segments underground and covering them with parkland. Whether called a lid, deck, bridge, or tunnel, there are already at least 24 of these parks in the country and a dozen more somewhere in the planning pipeline. Surprisingly, because of both undulating topographies and the fact that many cities are already operating on multiple above-and-below-ground levels, there are numerous opportunities to construct more freeway deck parks. As the impact of automobiles becomes ever less welcome in cities, these lids have moved from the novel to the accepted to, increasingly, the expected. The sometimes considerable cost has gone from being dismissed as “porkbarrel” to being redefined more positively as amenity investment with high economic payback.

Drivers passing through Seattle’s downtown core on I-5 go underneath the city’s five-acre Freeway Park, built in 1974.

In a study carried out by the Center for City Park Excellence in 2007, it was found that the average size of the nation’s freeway parks is about 8 acres and each covers about 1,600 linear feet of highway. Most famous is Seattle’s aptly named Freeway Park, designed by the Lawrence Halprin firm and opened with great fanfare in 1976, but the concept actually goes back to 1939 when Robert Moses constructed the Franklin D. Roosevelt Expressway along Manhattan’s East River, tunneled it under the mayor’s home at Gracie Mansion and constructed 14-acre Carl Shurz Park on top. In 1950 Moses did it again, in Brooklyn, when citizens rose up against a planned expressway through the center of Brooklyn Heights. As a compromise he added the 1/3-mile long Brooklyn Promenade with its supreme view of lower Manhattan, remarking self-satisfiedly at the ribbon-cutting, “I don’t know of anything quite like this in any city in the world.” The latest have been New Jersey’s innovative highway redesigns in Trenton and Atlantic City and the Rose Kennedy Greenway park blocks over Boston’s massive “Big Dig.”

The Interstate Highway System, when it was originally conceived in the early 1950s, was designed to link but not penetrate cities. By the 1960s, however, the distinction had been forgotten. Highways became the preeminent tool of urban renewal and redesign, and vast swaths of urban real estate were paved over. Waterfronts were blockaded in Portland, Cincinnati, Hartford, Cleveland, Philadelphia, and San Francisco. Nooses of concrete were wound tightly around the downtowns of Dallas and Charlotte. Trenches of noise and smog cut through Boston, Detroit, Seattle, and Atlanta. Stupendous elevated structures threw shadows over Miami and New Orleans. And wide strips of land were taken from large, iconic parks in Los Angeles (Griffith Park), St. Louis (Forest Park), Baltimore (Druid Hill Park), and San Diego (Balboa Park).

A few downtown parks actually survived the devastation thanks to the intervention of historic preservationists, including Lytle Park in Cincinnati and the National Mall in Washington, D.C. In both cases, citizen outcry forced the highway builders to tunnel underneath (although technically Lytle Park was leveled and then reconstructed three years later).

But it wasn’t until the construction of Freeway Park that the “deck the freeway” concept began getting some serious attention. Because of the constrained, hourglass geography of Seattle, Interstate 5 was a particularly damaging road, and the environmentally oriented populace was dismayed by the impact. “There was a large moat of traffic between downtown and historically residential First Hill neighborhood,” says Freeway Park Neighborhood Association President David Brewster. But the city was lucky–not only was I-5 sunk into a deckable trough as it passed downtown, but a former Seattle mayor, James “Dorm” Braman, had just been appointed assistant secretary of transportation for urban systems and the environment by President Richard Nixon. Braman was amenable to the deck, which was promoted by civic leader Jim Ellis and paid for under the city’s “Forward Thrust” bond initiative. Freeway Park opened in time for the bicentennial and garnered coast-to-coast attention. “It was a model for other cities to heal the scar that cuts right through a neighborhood,” says Brewster.

Freeway Park was beautiful and memorable, but it failed on one major count: acoustics. At 5 acres it couldn’t completely muffle the sound of traffic, and the park experience is accompanied by a constant white noise–not obtrusive, but not minimal, either. Phoenix’s 10-acre Hance Park seems to have solved the noise challenge (as has Seattle’s new, much larger Sam Smith Park). Labeled by the Phoenix New Times “a rare Phoenix instance of nature over traffic–in this case, literally,” Hance Park is decked over the Papago Freeway, uniting uptown and downtown and providing a park adjacent to the city’s central library. The freeway (Interstate 10) was originally planned as an elevated bridge through downtown but opposition by citizens and the Arizona Republic killed that idea in a 1973 ballot measure. Not until ten years later did the city finally accept a below-grade solution with the park as a key sweetener. Hance Park opened in 1992 and today is the site of a Japanese Garden. As a sign of success, it is gradually becoming surrounded by a growing number of upscale condominium towers.

By decking over a portion of I-35, Duluth, Minnesota, was able to save its Rose Garden and provide a park connection directly to its Lake Superior. Credit: Minnesota Dept. of Transportation.

Freeway parks have also bridged the divide between cities and their waterfronts. In Duluth, Minnesota, a plan to build Interstate 35 along the Lake Superior shoreline generated intense opposition from environmentalists and historic preservationists. By shortening the planned freeway’s length (and gaining the backing of powerful Duluth then-congressman John Blatnik) the city used the savings to pay for park covers. Ultimately, three different deck parks were built, including one that saved a historic Rose Garden.

Construction costs for deck parks can be wincingly high, but there is also an upside–the land itself is generally free, made available through air rights by the state transportation agency. In center-city locations this can amount to a multimillion-dollar gift. Land near the Santa Ana Freeway by Los Angeles City Hall, for instance, goes for between $2 million and $3 million an acre. In near-downtown San Diego by Balboa Park an acre is worth up to $13 million. Regardless of cost, the actual force driving–and making feasible–most deck parks is the opportunity for neighboring private development and redevelopment. In Trenton, the New Jersey Department of Transportation spent $150 million on the new 6.5-acre Riverwalk deck over U.S. 29, linking the city to the Delaware River. In response, notes Trenton Planning Director Andrew Carten, “The project resulted in a significant spike in interest and the sale prices of property. After all, would you rather look over 600 trucks barreling past every day, or a scenic park and river?” One lot, worth $120,000 preconstruction, was developed with six housing units that sold for $200,000 each. The presence of the park also helped recruit a new 82-unit market rate residential building.

The cost of the Boston Central Artery–the gargantuan project to bury the elevated Fitzgerald Expressway, which yielded as a surface byproduct the Rose Kennedy Greenway–has caused some people to doubt the feasibility of such parks in the future. But the Central Artery was primarily a transportation project that combined massive demolition along with even more massive construction. It also included major bridges and underwater tunnels. Of the $14-billion price tag, only an estimated $40 million was attributable to the mile-long stretch of four parks that opened to the public in October 2008. Certainly not inexpensive, but very much in line with many other new, showcase destination parks that are helping to redefine the nation’s premier urban centers.

The Woodall-Rodgers Park, planned over a three-block stretch of the Woodhall-Rodgers Freeway in Dallas, will connect the currently separated downtown and arts district from the Uptown neighborhood. Credit: Office of James Burnett.

Projects where freeways are already below-grade are more feasible, and four particularly high-prospect opportunities are currently being explored in St. Louis, Cincinnati, Dallas, and San Diego. In St. Louis, Mayor Francis Slay is promoting the “three-block solution,” a plan to cover a portion of I-70 between center city and the world-famous Gateway Arch. “We’re trying to get the annual 3 million visitors to the Arch into downtown St. Louis,” says Peter Sortino, president of the Danforth Foundation, which is handling the planning. “We’re also trying to help those already downtown more easily reach the Arch and the Mississippi riverfront.” An early estimate put the cost at a minimum of $40 million. Cincinnati faces the identical situation. An interstate highway, Fort Washington Way, is a barrier between downtown and the parkland along the Ohio River. Cincinnati had an opportunity to construct a five-block-long park deck during a road reconstruction (and narrowing) in 2007, but shied because of cost. As a compromise, the new Fort Washington Way was equipped with $10 million worth of steel pilings capable of supporting a future park.

Dallas, on the other hand, is plunging ahead with planning and funding a park over a stretch of the Woodall-Rodgers Freeway. The freeway separates the city’s downtown and arts district from the Uptown neighborhood, and a three-block park cover is seen as both improving the urban form and opening up new opportunities for development. A trolley line would run through the park, and condominium towers are expected to flank it on both sides. A developer of a nearby tower is enthusiastic, telling the Dallas Tribune that the park “will be a fabulous amenity to [my] building.” The park’s price tag is estimated at more than $60 million, but Dallas’s confident and ardent boosters are busily raising matching funds from private sources.

Trenton, New Jersey’s new 6.5-acre Riverwalk deck over U.S. 29 links the city to the Delaware River; it is credited with sparking development and reinvestment in nearby properties. Credit: Vollmer & Associates.

In San Diego, downtown interests are in the early stages of evaluating decking a few blocks of I-5 so as to forge a link with Balboa Park. The city has been in the midst of an unprecedented center city residential construction boom, and the highway presents a major barrier for the thousands of apartment dwellers who have little access to green space. Meanwhile, activists in Los Angeles are determined not to lose their “Freeway Capital of the U.S.” moniker and are evaluating eight different sites. “We want to now become the ‘Freeway Deck Park Capital of the World,’” said Don Scott, chair of the Hollywood Central Park Coalition.

Despite the cost of a park deck, there are numerous sources of local, state, and federal funds that can be cobbled together, particularly if an analysis shows that associated development will generate significantly more tax revenue. Often the deck superstructure is paid for by the federal government while actual park development is financed by the city: Phoenix spent $5 million landscaping Hance Park. The Trenton deck came about through reconstruction of a state highway and was paid for by the state of New Jersey. In Cincinnati, 20 percent of the narrowing of Fort Washington Way was financed through private dollars, including $250,000 from the Cincinnati Bengals football team.

Public Space Nouveau: Reclaiming the River Seine

A rendering shows the River Seine expressway converted to human public space.

The Mayor of Paris announced recently that the city is closing an expressway along the River Seine in a project that could have a major impact on public space in the city. Time magazine describes the current one-day-a-week closure and how this may spread to 365 days per year:

On a recent Sunday in Paris, stroller-pushing parents, rollerbladers and cyclists eased their way up and down an unusually tranquil stretch of the Seine’s left bank. Normally this road is filled with thousands of cars zipping along, but once a week it is transformed into an oasis of calm as part of an experiment by City Hall to see what happens when cars are banned from Paris’ riverbanks. So far the experiment, which has been going on for the past few years, is proving popular. Delphine Damourette, 31, a Montmarte resident whose cobblestoned neighborhood is a rollerblader’s hell, says the traffic-free Sundays give her a taste of her city as she most loves it — during summer vacation, when Paris slows down, cars disappear, and pedestrians reclaim the Seine. “It would be great if Paris were like this all year long,” she says. Soon, she may get her wish.

The banks of the River Seine are a UNESCO World Heritage Site, yet they are occupied by a motorway. Under the new plan, one side of the river would be converted exclusively to park-like space, while the other side would be converted to a parkway, leaving some space for auto movement.

Most likely, this premiere space within Paris will be popular with pedestrians all week just as it has been popular on the one-day per week closures. Critics argue that this will choke traffic and prevent a more egalitarian transportation system (i.e. in Paris, the poor largely live on the outskirts of the city and this would prevent them from having access, so the argument goes). This fails to acknowledge that visiting the renewed banks would not involve the expensive purchase of a private motor car, and that an existing and improved mass transport system can provide easier and cheaper access to the city.

In any case, if this experiment is a success in tightly packed and street-space poor Paris, then it seems more feasible for less traffic-jammed U.S. cities. It already has happened in a few places — the most well known being Portland’s Tom McCall Waterfront Park and a removed freeway in Milwaukee. There are tons of prospects to at least consider — from the central stretch of Civic Center Drive in Columbus, Ohio to the 10th Street Bypass in Pittsburgh along the Monongahela Riverfront (once proposed to be shut down by Mayor Tom Murphy) to the Potomac Parkway in Washington, D.C. and more. (The Congress for the New Urbanism has a list of “freeways without futures.”)

Such moves could make our cities healthier all around — through less air pollution and energy usage, increased pedestrian and bike safety, more places for physical activity and social enjoyment — which all leads to a greater gross urban happiness.

Video on Seoul’s Reborn Stream

Andrew Revkin of the New York Times provides a great video and backstory of the “daylighted” stream in Seoul, North Korea involving the tearing down of a highway and construction of the waterway and linear park.

Freeway Teardowns in New Orleans, Louisville?

We’re back with some more news on freeway teardowns, this time highlighting efforts in New Orleans and Louisville, KY.

A plan to tear down a segment of I-10 in New Orleans would result in this boulevard returning.

This last week an article appeared in the New Orleans Times-Picayune about that city considering tearing down a segment of the elavated freeway I-10. The idea is to replace the segment with what was originally on the same spot – a center median boulevard filled with trees known as Claiborne Avenue. The teardown would partly be done to bring back the surrounding neighborhood around that the highway construction helped deteriorate.

Another project in Louisville being proposed by the a local advocacy group would replace a portion of I-64 with a boulevard and riverfront parks (along the Ohio River) in and around the city’s central core. Under the plan being proposed by the group 8664, the current I-64 would essentially be rerouted through the construction of a new bridge up stream that would allow traffic passing through downtown to divert on other existing freeways further out. The groups prepared a video below — and their website has a background presentation.

Freeways to Parks

Tom McCall Waterfront Park in Portland, Ore., the site of a former freeway.

Next American City’s Daily Report writes about the Congress for the New Urbanism’s push for tearing down freeways in several cities.

Urban designers took the freeway, which was perfectly suitable as a connector between cities, and tossed it into the city itself……… It sliced through cities, severing their once-convenient grid systems. It blocked access to lucrative waterfronts and cleaved into neighborhoods.

And today we are left with a decision to make on this aging infrastructure: “Do they demolish the existing infrastructure to make way for surface roads and boulevards? Or do they invest in freeways yet again, when it makes even less sense to do so – given their crummy past and the ever-rising cost of gasoline?” CNU, arguing more for the first option, prepared a list of ten North American freeways ideal for demolition.

One of the best examples of a freeway teardown that already occurred is found in Portland, where the former Harbor Drive freeway was converted to a boulevard and the now very popular 40-acre Tom McCall Waterfront Park, named for the Oregon governor who helped make the teardown occur back in 1974.