Turenscape, a Beijing-based landscape architecture and urban planning studio, and Arsomslip Community and Environment Architect, a Bangkok-based studio, have transformed the site of a former tobacco factory in Bangkok, Thailand, into a low-maintenance forest park. The Benjakitti Forest Park provides a much-needed “green lung” in the busy center of the Thai capital. It regulates rainwater, cleans polluted water and provides a biodiverse habitat for wildlife. The park also provides a great recreational public space for residents of Bangkok's densely populated downtown.
Bangkok is a flat, low-lying urban area with an average elevation of 1.5 meters. Most of the area was once swampland used for agriculture and eventually for industrial purposes. In a region prone to monsoons, land subsidence is a major problem due to groundwater pumping - this, coupled with global warming, has increased the risk of flooding due to Bangkok's low-lying location and inadequate drainage infrastructure: urban sewage from heavy rainfall can overwhelm drainage systems.
The Benjakitti Forest Park in central Bangkok's Khonti district covers an area of 41.3 hectares. The former tobacco factory consisted of single-story warehouses scattered among the trees. The surroundings presented a particularly challenging context for Turenscape and Arsomslip: to the north, a canal polluted by urban sewage and sewage; to the west, a highway that cut the site off from an adjacent neighborhood; to the east, an artificial lake; to the south, a hospital, hotel and convention center. The two studios add, “Besides the challenging location, the budget for this project was ultimately limited to only US$20 per square meter and it had to be completed in a short period of 18 months. The project was overseen by the military, with very little experience and skills in landscape projects.” A small museum about a tobacco factory and a sports center were also needed for the park site.
Today, the site has been transformed into a “green lung” in Bangkok - a central park with a holistic ecosystem that addresses storm water and water pollution regulation and encourages biodiversity and recreation. To achieve this, Turenscape and Arsomslip employed a number of strategies.
Recycle and reuse.
Retain and incorporate all existing trees on the site and use all main roads in the site grid.
Utilize existing factory buildings for the tobacco factory museum and sports center.
Reuse demolished concrete for foundations and paving.
Create porosity and wetlands
A labor-saving cut-and-fill technique was used to create three wetlands, dotted with numerous islets, which transformed the industrial park's concrete soil into a spongy, porous landscape capable of holding storm water during the rainy season. The foundation and foundations of each islet were made of recycled concrete; new trees were also planted on the mounds.
Turenscape and Arsomslip designed the wetlands on two levels, with a deeper core area and a terraced shallow shoreline. The shoreline is connected to a linear wetland constructed along the north and west boundaries of the park. This filters polluted channel water, cleans 8,152 cubic meters of water daily and keeps the wetlands nourished during the dry season; in addition, it helps create lush vegetation.
A cut in the middle of the reclaimed roads creates a permeable biosludge and flower bed - this separates bike lanes and pedestrian paths and brings a human scale to roads that once carried heavy trucks.
Initiating a low-maintenance “messy nature
The park's diverse microenvironment blends low-maintenance vegetation that is constantly and spontaneously made more fertile by native species. “A symbiotic ecological relationship is expected between fauna and flora. The messiness of the landscaped wetland thus creates a new aesthetic of dynamism and diversity in contrast to the typical urban landscape,” said Turenscape and Arsomslip.
Create immersive places for people
The addition of multiple boardwalks along the edges of the shallow marsh immerses visitors in nature. In addition, a skywalk winds its way through the protected trees, connecting the park that was previously separated by major roads.
For Turenscape and Arsomslip, the design of Benjakitti Forest Park has proved successful. The recent summer floods in Bangkok did not affect the park and its immediate surroundings; the linear marsh filters enough water to feed the park during the dry season; ninety-one bird species have been seen in the park, helping to repopulate the area; and the park attracts thousands of visitors daily.
