Chengdu, China: Grey to Green

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Photo credit: Park City and Urban Regeneration Bureau of Chengdu Chenghua District

Photo credit: Park City and Urban Regeneration Bureau of Chengdu Chenghua District

Photo credit: Park City and Urban Regeneration Bureau of Chengdu Chenghua District

Photo credit: Park City and Urban Regeneration Bureau of Chengdu Chenghua District

Photo credit: Park City and Urban Regeneration Bureau of Chengdu Chenghua District

City: Chengdu
Country: China
2022 Awards: Entrant
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* This case study was written by the city and has not been edited by AIPH

Initiative: Grey to Green

To advance the city’s new ambition of building the first Park City in China, landscape architects and urban planners in Chengdu are called for to employ more detail-oriented management of the urban spaces, recycle the unused space in Chengdu downtown, and recover the leftover space generated by unreasonable planning. The Grey to Green initiative emerged as one of the solutions. The primary objectives of this initiative were to address the outstanding problems along the Chengdu-Mianyang express way, such as indiscriminate parking of vehicles, chaotic traffic, randomly piled debris, and poor hygiene; and to tap the potential of the leftover space under the flyovers by introducing greenery, sports and culture facilities. At Fuqing Flyover, we created a sport zone that went instantly popular among both young and old, and quickly became a model case of the initiative—we successfully turned what was a dead Grey structure into a lively Green sport zone.

The Fuqing Flyover project covers about 18,000 square metres and a length of about 1,000 metres. The whole section is themed on ‘fashion and sports. It is divided into nine beautifully named thematic areas including the Time and Space Corridor, the Rainbow Paradise, the Modern Flower Street, the Dancing Light and Shadow, the Fancy Sporting Courts the Community of Vibrancy, etc Altogether, we’ve built five basketball courts, two football pitches, two badminton courts, a skateboarding area, a street dance and skating area, among other sports facilities. What we deliver are not only a vibrant public space for sports, but also all-year-round services for the local community. The project is now fully completed and in smooth operation.

Three-fold benefits have been brought to the city.

  1. By creating an ideal space for sports and recreation, it enabled greener life for the citizens.
  2. With the introduction of thematic light shows and intelligent interactive facilities, it served as a good practice of the smart city vision.
  3. By ingeniously designing the under-bridge spaces and turning them into spaces for happiness, we promoted the city culture of ‘we care for everyone’.
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Addressing the urban challenge

Breadth of the issue – How are the problem(s) that are being tackled by your initiative affecting citizens/local businesses or a significant component of the local wildlife?

The grey-to-green spaces are urban green spaces that has been created in the process of urban renewal. They impact people’s health by providing them with an inexpensive (often free) and convenient recreational service. The grey-to-green spaces impact urban ecological environment by the ecological benefits of the material cycle and energy flow brought by the plants; thus, any urban green space that is safe, clean, and convenient would contribute to the city’s ecological balance. And they also deliver benefits to the general environment of the city as they can absorb carbon dioxide and harmful gases and release oxygen, increase air humidity, regulate temperature, reduce wind speed. They can also improve the natural ventilation in summer, conserve soil and water, reduce dust and noises.

Depth of the issue – How seriously are the problems being tackled by your initiative impacting the life of the citizens/businesses/wildlife concerned?

First, the use of the space underneath the flyover strengthened the integration of the urban greenway system and the surrounding urban functions. Second, the street spaces are put for more creative use. Mini squares, pocket parks, horticultural landscapes, cultural art walls and small public service facilities are now ingeniously arranged for this purpose. Third, with the utilization of the underground space, people no longer feel depressive when travel pass the long, narrow and enclosed passages. Fourth, by adding recreation, lighting, and directory signage functions, climbing plants, arts, tree lawns, the spaces are transformed into an active communal park and thus become windows of the city image other than the original purpose of serving the traffic. Fifth, the wide variety of plants added to the biodiversity and ecological stability of the city. Six, the city’s land-use efficiency improved by recycling the wasted land.

The power of plants and natural ecosystems to deliver benefits

How is the initiative shaped by scientific evidence of the potential for plants and natural ecosystems to deliver benefits?

The innovative ideas lie in the fact that we introduced new businesses of sports and culture to urban green spaces; recycled old factories and other non-residential buildings to serve new economy, new industries, and new business forms; and employed the riverfront spaces to develop arts and the cultural creativity industry.

Another distinctive feature of the project is how we have turned the wasted space into mufti-functional spaces that incorporate culture, sports, tourism and commerce, offering plenty of choices and great attractiveness for the citizens, whose needs we cared for the most.

Also, the project is exclusive in that we guided the market entities to participate in the design, construction, operation, and maintenance of the spaces. With such a participative approach, we managed to form a favourable environment for the construction of the Park City.

How has the city exploited the potential of plants and associated ecosystems to deliver more than one benefit?

Chengdu Park City Construction and Management Bureau was designated as the lead department to advance the project. At the same time, the municipal authorities for social governance, housing and urban construction, urban management, transportation, sports are all included in the collaboration. We convened several rounds of special meetings to set the objectives, timeline and pilot cases, discuss implementing measures, and make supporting policies. On 12 December 2021, we officially published the Three-year Action Plan for the Grey to Green Initiative, in which the lead department and collaboration mechanism between municipal authorities and district government are clarified. The document also clearly set the objective of refurbishing 200 spaces in 2021 and building 600 grey-to-green spaces in three years. Moreover, favourable policies on land use, financial support, administrative procedure, and the co-construction and sharing approaches have been formed.

Innovative and Collaborative Solution

How does the initiative show evidence of feasibility, including on-going financial and logistical support?

Over the years, the flyovers, standing in the middle of the streets, turned to the spaces beneath them dead corners and caused acute problems including indiscriminate parking of vehicles, chaotic traffic, randomly piled debris, poor hygiene, lack of sports facilities within the half-an-hour reach of the local communities, and sharp reduction of green spaces.

In general, the project revived small urban spaces. It enabled better services for recreation, sports, and disaster relief by adding greenery, making the landscape more beautiful, improving community services, and using modular and replaceable practices. It has brought four-fold impact on local communities:

  1. Life of the nearby residents has become more convenient and delightful, which in turn improved the well-being of the people.
  2. The increased outdoor space is positively correlated with rates of physical activity, which improves people’s mood and contributes to the overall healthiness of the residents.
  3. The businesses of the surrounding areas are greatly boosted; Fourth, more room is made for the wild birds in the city.
In what ways is the initiative innovative?

Firstly, it offered easier travel, better sceneries, and greater physical and mental health for the citizens. The regulated parking spaces, convenient traffic and well-organised roads will substantially improve the travel convenience and street views for the citizens, while the hygienic and clean sports zone will significantly contribute to their physical and mental health.

Secondly, it increased outdoor spaces. The creation of green sports zones provided more room for and increased the rates of physical activity, which improves people’s mood and contributes to the overall healthiness of the residents.

Third, it promoted the business in the surrounding areas. The clean, tidy, and multi-functional spaces under the flyovers are now attracting more people, while the evening operation hours are generating more revenue for the businesses in the surrounding areas.

Fourth, more room is made for the wild birds in the city when green spaces increase, so comes more harmonious relations between the urban dwellers and nature.

How is the initiative supported by collaborative working across disciplines and sectors?

We aligned the Grey to Green initiative with the Guidelines for the Planning and Design of the Leftover Spaces in Chengdu Downtown previously issued by Chengdu Municipal Bureau of Urban Planning and Natural Resources, and promulgated the Guidelines for the Construction of the Grey to Green Initiative (trial version).

On 12 December 2021, the municipal government issued the Three-year Action Plan for the Grey to Green Initiative.

With the joint effort of Chengdu Municipal Bureau of Market Supervision and Management, the Certificate Issuance Guidelines for Businesses under the Framework of the Grey to Green Initiative was published.

How does the initiative demonstrate evidence of community support?

The Fuqing Flyover project started in November 2020 and was completed and put into use in July 2021.

By the end of June 2021, 149 model cases of the Grey to Green Initiatives were completed; by the end of 2021, we achieved the objective of furbishing 200 grey spaces.

Implementation, Impact and Replicability

How does the initiative demonstrate evidence of a track record of success against pursued objectives?

First, financial support. The initiative is funded by the annual budget of the lead department and supported by the district governments. In the case of the Fuqing Flyover project, Chenghua District offered subsidies. Moreover, the lead department will deliver one-off award grants to the star cases once the three-year action plan is completed.

Second, logistical support. Both the municipal and district governments have given great support for the approval, implementation, monitoring and maintenance for the initiative. The district authorities, to which the projects belong, offered strong support from the perspectives of market supervision, fire control and public health, just to name a few. In particular, the administrative procedures of the project all run on a fast track and are given priority.

How has the initiative had a ripple effect beyond the scope of the initiative itself, thereby demonstrating a change in the city’s and/or its partners’ way of working with plants?

Upon completing the Fujing Flyover project, residents of the nearby communities all spontaneously came to experience the sports zone and examine the effect. The adorable toddlers, spirited teenagers, busy middle-aged adults, and senior citizens, all thumbed up for the project, saying they felt real happiness and greater sense of belongings.

How have other cities expressed interest in the initiative, or what potential does it have to interest other cities and be customised to their own circumstances?

Ideas for improvement: 1) continue to tap the potential of the leftover urban spaces; 2) to build platforms for social participation, guide more market players to participate in the design, implementation, operation and maintenance of the projects, and organise design competitions to serve the projects; 3) to build on the model cases and further explore operation models such as the “EPC+O” model(Engineer, Procure Construct Operation) and the ‘ proper-use management’ model, and set standardised procedures for market supervision, fire control and health licenses within the target areas. 4) as the city is about to host the FISU World University Games in the summer of 2022, to create the atmosphere of the Games and further integrate the initiative into the city’s urban renewal.

The innovative use of space under the Fuqing Flyover unlocks the hidden value of dead spaces – sterile pockets of land that result from infrastructural development. These dead spaces are often found under viaducts, bridges and flyovers or tunnels.  Activating these sterile spaces at a low cost could encourage city planners, entrepreneurs to test out new and sometimes unconventional ideas in the heart of the land scarce city.

Sustainability and Resilience

What efforts have been made to reduce the carbon footprint of the initiative?

The initiative triggered the ripple effects of

  1. More detail-oriented management of urban space.
  2. More businesses are developed for the leftover spaces.
  3. As communities begin to improve their urban green spaces, other areas will be forced to stay competitive and beautify their areas as well.
How have the anticipated impacts of climate change been considered?
  1. More new approaches are adopted of the reshaping of the city landscape.
  2. Micro parks become the new trend and citizens begin to enjoy more of the urban parks.
  3. More ideas on social participation and co-construction are promoted when operation models like the ‘EPC+O’ model are introduced.
  4. More vigour and vitality and greater sporting vibes are introduced to the city, which turned it more and more attractive.
What processes does the initiative include for it to be considerate in its use of soils and other natural resources?

The initiative reduces the carbon footprint in urban spaces with the following endeavours:

  1. Selecting more environment-friendly materials. Low carbon materials are preferred in selecting construction materials.
  2. Reducing traffic and enhancing the treatment and recycling of construction waste.
  3. Conserving water and improving sewage treatment. During the construction process, sewage is treated promptly, and chemical materials are isolated from the environment. Water-resisting layers are installed to prevent chemical contamination.
  4. Employing more science and technology for the maintenance and applying green low-carbon construction techniques.
  5. Reasonably planning the construction process and choosing the most appropriate machinery for each step.

Monitoring, Maintenance, and Management

How has the initiative been designed and implemented so that long-term needs for management and maintenance are reduced and can be met?

By incorporating the concept of sponge city and through the scientific measures for each construction procedure, i.e., infiltration, retention, storage, purification, use and discharge, the impact of urban development on the ecological environment is minimized. The sponge city measures also effectively controlled pollution, met the standards of urban flood prevention and control, enhanced water recycling, and maximized the resourceful use of rainwater.

What protocols are in place to facilitate monitoring of results?

We encouraged the third-party professional companies to participate in the investment, construction, and operation of the projects through leasing, co-operation, and Operations and Maintenance (O&M.) We combined non-profit measures with market-based approach to offer sustainable and high-quality services to the neighbourhoods.

How has the initiative been enhanced in response to monitoring of results?

During the construction process, we enhanced the recycling of soil resources.

  1. The backfill soil comes from what has been excavated from the same spot.
  2. When the excavated soil doesn’t meet the demands, soil from nearby construction sites is preferred.
  3. Drinking water and other high-quality water has been avoided for the construction.