Strengthening Infrastructure Resilience to Extreme Weather in Northern Metropolis
Ms. Olivia TO, Project Manager, Institute for the Environment, HKUST
Prof. Zhongming LU, Assistant Professor, Division of Environment and Sustainability, HKUST
Dr. CT LOW, Geospatial Risk Lead, CWR
Under the new government structure, there will be three new deputy ministers to “provide higher coordination for large-scale regional developments such as Northern Metropolis (NM)”. Climate change should be one of the important cross-bureaux issues for them to address.
Hong Kong is experiencing extreme weather events such as rising temperature and more intense rainstorms. Low-lying coastal areas are susceptible to storm surges and sea level rise. For instance, the residential communities in Heng Fa Chuen in Hong Kong Island, and Yuen Long within the NM, were severely flooded and buildings swayed during the passage of Super Typhoon Mangkhut in 2018. Land, sea and air transportation were paralysed during the typhoon, and electricity supply was disrupted in some places. In developing the NM, climate resilience is an important consideration.
Ensuring buildings and infrastructure systems are resilient in face of extreme weather events requires a sustainable, innovative and multidimensional approach in infrastructure planning.
Adaptive infrastructure and urban resilience
The Hong Kong government recognizes the need to "adopt a comprehensive strategy on climate change adaptation and resilience to protect the life, health and property of the people from extreme weather and strengthen the resilience of the community", as stated in Hong Kong's Climate Action Plan 2050. The development of the NM requires an overarching climate-resilient strategy, which is missing in the Northern Metropolis Development Strategy at the moment.
As a low-lying coastal city, Hong Kong’s public infrastructure and buildings need to be planned and designed holistically to ensure transformative resilience as suggested by the latest IPCC’s Sixth Assessment Report Working Group II (AR WGII) report. Measures such as stepping up coastal defence systems by wave walls, stabilising slopes by blue-green infrastructure, strengthening facilities such as water sewage plants and piers, and embracing innovation technology, are important.
A recent report released by Organisation for Economic Co-operation and Development (OECD) noted that the operation and maintenance of infrastructure will be transformed by the adoption of new technologies and data science which encompass earth observation, remote sensing, big data, Internet of things and AI. The Hong Kong government can pay greater attention to the interdependency of multiple systems and check them against climate vulnerabilities, the learning from which could be applied to developments, including the NM.
Regional collaboration of risk management
Extreme weather events may cause infrastructure and systems malfunction. Considering that the NM is situated between the borders of Hong Kong and Shenzhen, strengthening regional collaboration through an interdependent and interconnected network of critical infrastructure, in particular electricity, water, drainage and transport could ensure systemic risks could be addressed effectively and in a timely manner. It is important to formulate a regional emergency response and recovery strategy, as well as to develop the vulnerability- informed decision support systems, for the effective management of interdependent infrastructure systems. This can ensure the city’s preparedness on managing and reducing disaster risks to public safety, infrastructure and property.
Flood-prone residential areas
The NM has two district administration areas - Yuen Long District and North District - with a total land area of about 30,000 hectares to provide about 900,000 residential units for 2.5 million people. According to a recent consultancy study released by Civil Engineering and Development Department (CEED) in May 2022, Yuen Long North West and Central, including both town centre and coastal areas, are high flood risk areas in light of climate change. This should require careful planning to address the risks from more extreme rainfalls, typhoon-related storm surges and sea level rise.
Given the current policy and actions globally, the sea level rise is likely to accelerate. This has also led to the IPCC to warn that 2m to 5m of sea level rise by 2100 and 2150 “cannot be ruled out”. This is why the Hong Kong government will need to enhance coastal defense strategies and raising the level of reclamation. At present, the maximum sea level has already been shown to rise 4.18m at Tsim Bei Tsui (which is within the NM) during typhoon.
High-level coordination and investments
The government pledged in its Climate Action Plan to "allocate about $240 billion in the next 15 to 20 years to implement mitigation and adaptation measures to combat climate change” which covers energy saving, green buildings, green transport, waste management relating to mitigation, as well as coastal protection, slopes and drainage systems relating to adaptation. Meanwhile, the Financial Secretary committed in the 2022-23 Budget that "$100 billion from the cumulative return of the Future Fund to set up a dedicated fund under the Capital Works Reserve Fund in order to expedite the implementation of infrastructure works relating to land, housing and transportation within the Northern Metropolis." These are large sums of money. Bureaux and departments must design and plan the NM as a climate-resilient and biodiverse development. Development Bureau and the expanded Environment and Ecology Bureau should work closely together, which requires effective coordination and communication. The new deputy secretaries have their work cut out for them.
Furthermore, the Climate Change Working Group on Infrastructure under the leadership of CEDD has been conducting a number of resilience studies on coastal infrastructure, buildings, drainage, water supply and sewage facilities. These studies should be released as some of them have been completed and there is great public interest in them, and so that people can contribute in a positive manner.
In summary, Hong Kong has accumulated experiences in face of more extreme weather events, building a climate-resilient city relies heavily on the solid foundation of our urban infrastructure designs. The city can reduce its climate risks through early planning based on science and active regional cooperation. The new government should step up its efforts in a timely and coordinated manner to combat climate crisis.