The climate resilience challenge for Hong Kong
By Angela TAM
Not many held much hope for the 2015 Paris Climate Conference, or 21st Conference of the Parties to the United Nations Framework Convention on Climate Change (COP21), after the dramatic failure of the conference held in Copenhagen six years ago. However, with recent weather events demonstrating the impact of global warming and 1 deg C of temperature rise already locked in, delegates to COP21 were able to arrive at an agreement after negotiating through many nights without much sleep.
What made the agreement possible was the willingness of delegates representing almost 200 developed and developing countries to set aside their differences to reach the deal. The two key points of the agreement are:
- Holding increase in global average temperature "to well below 2 deg C above pre-industrial levels and pursuing efforts to limit the temperature increase to 1.5 deg C above pre-industrial levels"
- Providing the necessary funding to poor countries to help them reduce emissions and mitigate the effects of climate change
Despite the agreement, there is widespread acknowledgement that the hard work has only just begun. How will Hong Kong act in light of the agreement? Hosting a Hong Kong session at the China Pavilion at COP21, Secretary for the Environment K S Wong had said that the city would develop as a low-carbon city, with a new target of reducing its energy intensity by 40% by 2025.
Climate resilience roadmap
While the COP21 negotiations were still ongoing, the Business Environment Council (BEC) released its "Hong Kong Climate Resilience Roadmap for Business" report, highlighting ways in which the business community could contribute to the city's climate resilience.
In what ways is Hong Kong vulnerable? The BEC report cites five direct and indirect impacts of climate change:
1. Floods, landslides, and storm surge made worse by sea level rise, more extreme typhoons and heavy rainfall
2. Heat stress affecting people, infrastructure and energy use
3. Water scarcity as demand grows and the risk of drought increases
4. Health risks from increased incidence of disease
5. Supply chain risk caused by disruption to transportation and production
The report offers five recommendations, namely:
1. Risk assessment to identify the major risks from climate change
2. Development of contingency plans to cope with extreme weather events and effect disaster recovery
3. Cooperation across industry sectors
4. Developing cross-sectoral benchmarks
5. Developing knowledge of best practice and innovating through use of new technologies and approaches
According to Ir Bruce Chong, Arup's East Asia Sustainable Infrastructure Design Leader, who also took part in the BEC study, the level of climate change awareness and resilience in Hong Kong differs from sector to sector. The level is high among the utility companies because of their commitment to supply reliability, for example, but organisations in the supply chain industry are not uniformly aware or committed. Whilst some large fashion manufacturers have commissioned their own studies of climate change risk, others are less prepared.
In terms of its infrastructure, Hong Kong is already making headway.
"Well planned and executed infrastructure is a key contributor to Hong Kong's climate resilience. For example, the commitment to have rail as the backbone of Hong Kong's transport system is being maintained with four new or extended lines planned to come into operation over the next few years. Further extensions of the rail network are also being considered into areas which are currently not being served by rail," said John Blackwood, Atkins' director for transport in Asia Pacific. "This improved accessibility and passenger route choice will help reduce the reliance on road-based transport systems with further benefits to the environment and also the general quality of life in Hong Kong."
Much work has also been done in recent years to improve the city's drainage network, with the completion of the large-scale stormwater drainage tunnels to divert rainwater from heavy downpours away from low-lying areas. Hong Kong is also a world leader in slope stabilisation. According to the Geotechnical Engineering Office (GEO) of the Civil Engineering & Development Department, GEO has let, on average, ten consultancy agreements and 13 works contracts for landslip prevention and mitigation each year. About HK$19.6 billion has been spent on these studies and works to date and thousands of man-made slopes have been upgraded under the programme. GEO has also turned its attention to natural hillsides, with mitigation measures having been carried out on natural hillsides around the city. With landslides threatening so many places around the world, GEO may be expected to host more and more visitors seeking solutions to the life-threatening problem of dangerous slopes.
However, climate resilience needs to be taken into account in the early stages of infrastructure planning, Ir Chong emphasised, and both the Government and businesses must work together.
"The Government could provide more detailed data relevant to specific industries, to help them plan against climate risk," he said.
There is of course an important role for engineers to play, but business opportunities will come along with their own climate risks. For example, building stronger sea defences will require engineering expertise, but as the weather becomes hotter, engineers will have to factor in not just infrastructure design but also financial implications and workers' safety.
"When construction sites become too hot, work will have to be suspended. When there are storms and heavy rain, again work will have to be suspended. Contractors will have to take these factors into account when they price a project. Will there be government guidelines to help them? Supply chain resilience will impact on materials availability. Some materials can be made locally to reduce the risk but not all materials can be made in Hong Kong," Ir Chong said.
Emma Harvey, group sustainability and CSR manager of Gammon Construction Ltd, offered a contractor's perspective.
"Impacts from climate change are only likely to significantly affect pricing if the construction sector continues to operate with a 'business as usual' approach," Ms Harvey said. Climate change is likely to influence total project cost, however, due to the design changes that will be required for climate change adaptation and resilience of projects. For example, designs will need to withstand higher sea levels, more extreme storm surges, higher temperatures, greater wind loads and higher rainfall. These more stringent design specifications will obviously need to be included in contract prices. Contractors will also need to address these potential impacts in their site works, for example, increasing the sizing for the temporary site drainage systems.
"If restrictions are placed on working conditions, for example, stopping work if the heat and humidity reaches above a certain limit, or if extreme rainfall events occur more frequently then this could also increase costs due to extensions in programmes."
In terms of the carbon emissions from construction materials, both the Construction Industry Council (CIC) and the Hong Kong Green Building Council (HKGBC) have launched carbon labelling schemes covering a range of construction and architectural materials. CIC's scheme currently covers Portland cement, reinforced bar, structural steel and ready-mixed concrete. Three more materials are likely to be covered by the scheme this year, although CIC has yet to determine which ones they will be.
Under HKGBC's Green Product Accreditation and Standards (HK G-PASS), which was launched in January 2015, 25 product categories will be covered by the labelling scheme under two phases. HKGBC has also launched the Benchmarking and Energy Saving Tool (HK BEST), to promote building energy efficiency in office buildings. The green building certification body, BEAM-Plus, is encouraging the industry to embrace these schemes by including "use of certified green products" in their certification assessment of new buildings.
To turn Hong Kong into a low-carbon city, such efforts will need to be supported by new technologies as well. Internet-connected sensors that make up the Internet of Things (IoT) phenomenon will not only contribute to the development of smart cities, but also ones that are climate-resilient as they will help cut energy use and monitor the conditions of structures, traffic and other facilities.
Smart + green + resilient
Ir Chong suggested a new concept: smart + green + resilient, or SGR. Integrating these three concepts in infrastructure and urban planning means applying appropriate technologies to reduce greenhouse gas emissions and enhance climate resilience. For example, Hong Kong need not follow the typical renewable energy path by increasing its deployment of wind turbines and solar panels, as data gathered over the last five to ten years has shown that neither option is capable of generating much power in Hong Kong.
However, the deployment of small-scale biofuel plants is a viable option given the amount of waste generated and the need to transport that waste over long distances for disposal at landfills that are fast running out of space. Having small, district-level incinerators would improve supply-side resilience by diversifying supply. At the same time, the approach could reduce carbon emissions associated with the transport of waste to far-off landfills and make it possible to recycle the waste heat generated for district heating.
"In New York, many large power plants were taken out of commission by Hurricane Sandy but smaller, regional plants were able to continue operating," Ir Chong observed. "Should we continue with the model of centralised power supply or adopt a more decentralised approach? Let's have more research to determine which is more suitable for Hong Kong."
To succeed in having a low-carbon city, it seems, calls for much progressive planning and re-thinking.
Ms Harvey summed it up thus: "The best long-term carbon savings can be achieved, however, at the early design stages of a project. For example, through optimising passive design such as optimising orientation, natural light, shading, insulation against solar gain, etc. Taking a truly integrated, systems-thinking approach to sustainable building design from the outset of the project can ensure these operational benefits are realised, before consideration is given to specific 'low carbon' materials. Involving contractors early, optimising designs and selecting alternative materials can also reduce carbon footprint in terms of the embodied carbon of a project. If clients are able to support an integrated design approach coupled with specification of more sustainable materials, the project will have the best chance of achieving a low carbon footprint."
Applying this approach to the whole city will be a challenge indeed.
Coastal areas that will be flooded with a 6 m sea level rise is shown in red. Image: NASA
Flooding in Thailand (right) in 2011 severely affected supply chains. Image: Jesse Allen and Robert Simmon
A mudslide near Washington in the US in 2014 engulfed a neighbourhood. Landslides have affected communities around the world. Image: Matthew Sissel
The PolyTechnic University of Hong Kong has developed cooling vests to protect construction workers from heat stress. Image: PolyU
Hurrican Sandy crippled New York but smaller, regional power plants were able to continue operating. Image: David Shankbone