Over the past decades, Shanghai has seen rapid urbanisation and population growth. The massive scale of urban development has increased the impermeable area for the catchment while reducing green space leading to increased stormwater runoff across the city. This has caused serious urban flooding and river pollution in recent years. Shanghai needs an upgrade to its existing drainage system to support future vision to an Excellent global city in 2035.
With the existing drainage system challenge in both old and newly developed areas – coupled with imminent threats of climate change bringing more rainfall – in December 2018 the city authority launched a design competition to look for advanced yet implementable strategies for the highly populated city centre from overseas experts.
Drawing upon our global expertise, Arup partnered with Shanghai Urban Construction Design & Research Institute to tailor a plan that covers 640km² with a population of 15 million.
640km² planned area
Global perspective for local challenges
After reviewing the previous drainage masterplan and studying relevant cases across the globe, we challenged the traditional approach of focusing solely on drainage. Instead we proposed a visionary ‘blue, green and grey’ approach to support an integrated water cycle within the city which will also benefit other aspects across greater Shanghai, including ecology, economy and public health.
We also studied a number of global cities, including New York, Singapore, Philadelphia, New Orleans and Rotterdam, to identify those that align most closely with the specific challenges faced by Shanghai.
Our proposed strategy also follows that of other megacities, which are increasingly looking at climate change adaptation, water sensitive urban design, integrated flood control planning and decentralised infrastructure as key components of future water strategies.
Introducing green and blue infrastructure
Based on the Arup-developed ‘design with water’ framework, our approach seeks to maximise the potential of current facilities and existing infrastructure before proposing anything new, with an initial focus on improving the management of the existing network.
Green infrastructure is an approach to water management that protects, restores, or mimics the natural water cycle. We first conducted a detailed analysis of the land uses of the Shanghai urban area using our understanding of the city’s history to establish a total of 12 different types. By applying remote sensing imagery and machine learning technologies , we were able to categorise the study area into different development types with respective green infrastructure used accordingly.
Rivers play a very important role in urban drainage. An urban flooding model has been built in order to find opportunities and challenges of using this blue infrastructure. This was the first-ever model to integrate the river and drainage network in Shanghai.
Finally, where there is no other option, we looked into the implementation of grey infrastructure.
Our integrated system brings additional urban elements above ground into storm water management functions, including roads, green space, rivers and other open spaces.
Arup’s next-generation blue and green infrastructure will be integrated into all urban projects, from urban network systems to individual buildings. It will also be integrated with other critical infrastructure including transportation, water, energy, digital and waste, for urban planning, design and urban redevelopment.
Contributing to a sustainable future
The success of this masterplan enriches Arup’s ‘Design with Water’ framework. In particular, the idea of a water-orientated urban planning approach will be a showcase to next generation urban ecological development.
Effective management of the water environment is critical to achieving the United Nations’ Sustainable Development Goals (UN SDGs), as the UN also describes water as “a common currency” which “links nearly every SDG and which will be a critical determinant of success in achieving most other SDGs”.
Next, we will work closely with the Shanghai authority to implement the plan for this city shaped by water – helping the city to not only meet its stormwater improvement target, but also build climate change resilience and provide better wellbeing for its people.