By Karen Stephenson

Over the past three decades, urban sprawl has quickly swallowed up thousands of acres of open space and has left a landscape of bricks, mortar, concrete and asphalt in its wake. Some cities and suburban communities, however, have become creative in developing new green spaces when faced with demolishing old structures or beautifying current green areas.

St. Louis, Missouri

Gateway Mall was once a strip of green space that many people viewed merely as a divider between the north and south of St. Louis. The St. Louis-based Gateway Foundation has transformed these 2.9 acres into a spectacular new urban sculpture park that's now an exciting, people-friendly gathering spot.

In 1983, the Pride of St. Louis Redevelopment Corporation demolished the Title Guaranty Building in order to construct the Gateway Mall. This group eventually tore down the Buder and International buildings, therefore expanding the green space.

Gateway Mall was renamed Citygarden and is now home to many works of art that can be appreciated by the 12,000 workers in the office towers that border this parkland, by tourists or those who venture into the city for the day.

In addition to the 24 works of art by international artists, Citygarden's exquisite landscaping was professionally designed and includes native plants, shaded pathways and water features that make it aesthetically pleasing.

Sudbury, Ontario

The mining industry caused severe environmental damage in Sudbury and the surrounding areas. By the mid-1970's, vegetation on over 100,000 hectares of land in Greater Sudbury had been destroyed, leaving a barren landscape.

In 1973, VETAC, Sudbury's volunteer Re-Greening Committee, embarked on a project that has spanned three decades. Although the community had attempted to replant lost trees, VETAC's method of applying fertilizer, limestone and grass seed was the key in getting saplings to take root and flourish.

The City of Greater Sudbury has adopted VETAC's methods and they work closely together on the Land Reclamation Program to re-green Greater Sudbury. To date, this ambitious program has planted approximately 8.8 million tree seedlings, 50,000 bushes and limed over 3,000 hectares of barren land, transforming it into healthy grass.

New York City, New York

High Line Park is proof that a city can elevate a park to new heights. The High Line was constructed during the Great Depression to remove dangerous freight trains off Manhattan's streets. This line was active until 1980.

During the 1990's, this stretch of abandoned railway line was covered over by tolerant wild grasses, forbs and trees. In 1999, community support to redevelop the High Line for pedestrian use started to gain momentum and by 2004, funding was allocated to transform this old, elevated rail line into parkland. On April 10, 2006, construction officially began and the first section of this innovative park opened to the public on June 9, 2009. The middle section is currently being developed; meanwhile, the northernmost section's future is uncertain at this time.

High Line Park is now home to naturalized plants inspired by the self-seeded landscape that grew around the abandoned rail line. There are a total of 210 species of meadow plants, grasses, liatris, coneflowers, sumacs and smokebush that adorn this creation, and pebble-dash concrete walkways sway from side-to-side throughout this elevated park.

Hayes Valley, California

The Central Freeway once sliced through this neighborhood but after the Loma Prieta earthquake, better known as the Quake of '89 or the World Series Quake, this freeway was shut down. It eventually faced demolition, leaving a strip of empty space and parking lots. Although a section of the freeway was rebuilt, a large area of this once-busy freeway was transformed into green space.

The new design of the area pleased local Hayes Valley residents because what was once the end of a freeway, is now parkland and a playground. People who reside there are thrilled that this badly-needed green space occupies a part of their community. In 2005, this parkland was a showcase for a temple structure for David Best, an internationally-renowned American sculptor.

Seoul, South Korea

For decades, a tunnel of crumbling concrete has encased the Cheonggyecheon stream, buried beneath a highway and elevated expressways in Seoul. This stream was a centerpiece of the city for 600 years before it was entombed by asphalt in 1958.

Seoul needed to transform into an environment-friendly city so its citizens can have pride in their community. Although the covering of the Cheonggyecheon stream was prudent in the early years of economic development, South Korea has recently become affluent and environmental protection is a concern.

An ambitious project, completed in 2009 and costing approximately $384 million, has brought the Cheonggyecheon stream back to life, along with lush green plant life and parkland for visitors to enjoy. The stream was uncovered four years ago, in 2005, and data show that the eco-system has greatly improved. The number of fish species has risen from 4 to 25, bird species have increased from 6 to 36 and insect species have soared from 15 to 192.

Cities from Singapore to North America have been resuscitating rivers by transforming storm drains back into streams. Building green corridors around exposed waterways can easily bring a natural environment into an urban setting.

More Projects in the Works

A stretch of Philadelphia's waterfront is turning 14 acres of asphalt into green space by 2011. The $40 million Penn Park project will include athletic fields, tennis courts and a raised central plaza with views of the skyline.

Flint, Michigan, the birthplace of General Motors, lost half of its population with the downfall of the auto industry and the pull toward a smaller city is in the forefront of its recent planning strategies. GM's "city-within-a-city" once covered 235 acres; now all that remains are a lot of abandoned areas. Parks and community gardens are planned for this area.

Shut-down factories and vacant neighborhoods are peppered throughout many cities, from Buffalo to Milwaukee. Many communities have already transformed abandoned properties into parks, gardens and other open spaces.

Worldwide, more and more cities are looking to transform old bricks, mortar and asphalt into green spaces for people to enjoy. It's been a long time coming, but for those who are reaping the rewards of these green transformations, they say it's been worth the wait.