Primary Hazard Profile
6 hazards documented · 0 citywide exposure · 0 worsening with climate change
| Hazard | Exposure | Severity | Probability | Climate trend | Source |
|---|---|---|---|---|---|
OverheatingR2DescriptionIncreasing temperatures and the frequency and length of heatwaves will be made worse in the City due to urban heat island effect. This is when dense urban areas remain significantly warmer than the surrounding countryside, due to roads and buildings absorbing and retaining heat in the day and re-emitting it at night. We are increasing greening across the City to provide more shade and reduce the impact of the urban heat island effect. We require new developments to consider including green roofs, solar shading and planted areas, with the added benefit of reducing buildings’ energy consumption. LocationSquare Mile residents are disproportionality elderly, and workers are predominantly professional workers, 20 33% of whom suffer long-term physical ill-health conditions. 21 Both of these factors increase risks of heat-related ill-health. 56% of domestic EPC ratings awarded between 2017-2018 in the City of London were rated C or less efficient. The borough has over 600 listed buildings and an aging building stock, in turn it is expected that a significant proportion of the existing building stock will be challenged to cope with overheating conditions. Current responseThe City Corporation has considered overheating risks through its Transport Strategy, planning requirements and work on its Joint Health and Wellbeing Strategy.34 Retrofit programmes are increasingly popular, with the Greater London Authority and other public bodies increasingly moving towards providing funding and support for retrofitting homes to build resilience. Strategies to minimise overheating risk are often, but not always, built into refurbishment cycles by commercial asset owners. | Square Mile residents are disproportionality elderly, and workers are predominantly professional workers, 20 33% of whom suffer long-term physical ill-health conditions. | Increasing temperatures and the frequency and length of heatwaves will be made worse in the City due to urban heat island effect. | — | The City Corporation has considered overheating risks through its Transport Strategy, planning requirements and work on its Joint Health and Wellbeing Strategy. | |
FloodingR1DescriptionIt is anticipated that the City will experience a change in both the frequency, intensity and season variability of rainfall in the future, which will put pressure on our drainage system. As the Lead Local Flood Authority for the Square Mile we're requiring new developments to include sustainable drainage system which will slow down the flow of water. In addition, the City’s stretch of the Thames is tidal and will be affected by rising sea levels. The City is currently protected by river defences and the Thames Barrier downstream. In 2021, we adopted our Riverside Strategy in line with the Thames Estuary 2100 Plan to ensure these defences are resilient in the future. You can find our more about flooding and the work of the Lead Local Flood Authority on our Flooding pages . LocationFor 40% rainfall increases under climate change,16 surface water floods could extend to cover an additional substation, and numerous commercial and residential properties.7 Future river flood risk similarly will affect additional properties and infrastructure over today’s levels. A number of critical utility lines run at a deep level below Farringdon Street.6 Whilst likely designed with future climate in mind, potential impacts of extreme events on the functioning of these assets should be considered. The risk of groundwater flooding in the context of climate change is less well understood than other types of flood risk. Preliminary research suggests that groundwater levels will fall, reducing flood risk.17 Current responseFlood defences for river flooding are currently maintained by riparian owners under a comprehensive programme of works by the Environment Agency and TE2100 plan. 18 Surface water flooding is controlled by urban drainage systems, and groundwater flooding through the GARDIT system. Activitiesexist to incentivise and encourage greater numbers of Sustainable Urban Drainage – including through planning requirements for minimum urban Greening Factors on developments. | For 40% rainfall increases under climate change,16 surface water floods could extend to cover an additional substation, and numerous commercial and residential properties... | It is anticipated that the City will experience a change in both the frequency, intensity and season variability of rainfall in the future, which will put pressure on our... | — | Flood defences for river flooding are currently maintained by riparian owners under a comprehensive programme of works by the Environment Agency and TE2100 plan. | |
Water stressR3DescriptionChanges in rainfall patterns will impact on London’s capacity to meet its water demand, which can lead to drought. Droughts are expected to get longer and occur more frequently, with double the number of days of drought predicted in 2050 compared to 2020. We are trialling climate resilient planting in our gardens and open spaces to minimise water consumption, and are encouraging water efficiency measures in new developments through our planning policies. LocationRegional water shortages could bring intersecting disruption through knock-on effects on irrigation for agriculture, energy production and ecosystem disturbance. Non-domestic buildings typically have one day’s water storage, meaning water stress could have implications for productivity. With no reservoirs and little additional space of its own, the Square Mile is dependent on water from Thames Water, with few options for diversification. Current responseThe City Corporation works closely with Thames Water in the instance of leaks of water shortages and public communications campaigns are used during hosepipe ban periods, with measures taken to try to reduce demand and water consumption. | Regional water shortages could bring intersecting disruption through knock-on effects on irrigation for agriculture, energy production and ecosystem disturbance. | Changes in rainfall patterns will impact on London’s capacity to meet its water demand, which can lead to drought. | — | The City Corporation works closely with Thames Water in the instance of leaks of water shortages and public communications campaigns are used during hosepipe ban periods,... | |
Biodiversity lossesR4DescriptionChanges to the climate can fundamentally alter natural trends and cause decline and loss within ecosystems. This includes disruption to pollination systems, carbon storage capacity and our dependence on the natural environment for our wellbeing and resources. While only a small proportion of the City is covered by gardens, parks and water, we are working to improve the connectivity of these natural spaces to combat losses to biodiversity. Our Biodiversity Action Plan focuses on managing our existing green spaces to benefit biodiversity, which is increasingly important as we look to natural solutions to mitigate flooding and improve air quality and shading. LocationKey urban species have habitats in the Square Mile, including bats, bumblebees and Peregrine Falcons.25 Connectivity of green space across London and continuous ecological corridors are important for species across London, not just in the Square Mile. Outbreaks of pests and diseases among plant populations are critical risks in England (see risk 6). Current responseUrban greening initiatives and green space management are core City Corporation functions. Through the actionsv within the Biodiversity Action Plan 25 the City Corporation has undertaken numerous studies and research exercises into management of its open spaces, though this strategy suggests improvements to the plan are required | Key urban species have habitats in the Square Mile, including bats, bumblebees and Peregrine Falcons. | Changes to the climate can fundamentally alter natural trends and cause decline and loss within ecosystems. | — | Urban greening initiatives and green space management are core City Corporation functions. | |
Pests and diseasesR6DescriptionChanging seasonal conditions and global patterns will influence the spread of new and emerging diseases, while pests and invasive non-native species may also increase in number and range in a warmer, wetter atmosphere. The City, with its high density of people and infrastructure, makes the likelihood and consequences of disease outbreaks particularly acute. The urban heat island effect, complex international movements of people and trade and a variety of available habitats all make the introduction of non-native invasive species more likely. Some diseases show climate sensitivity with seasonal variation. LocationStudies note that urban trees are at particular risk of new pathogens and pest outbreaks, since the global trade in ‘plants for planting’ is a pathway for their accidental introduction.30 Equally, the UK Plant Health Risk Register contains approximately 1,000 existing pests and diseases. Changing climatic conditions may increase survival rates of existing pests and diseases, in turn increasing risks, particularly to vulnerable species. Strain on medical infrastructure, which is already limited in the Square Mile may increase substantially under rising spread of pests and diseases. Advice indicates that disease outbreaks will disproportionately affect dense urban areas. The City Corporation can have a role in managing urban flow and transition through its transport strategies and management of open spaces, as seen during the COVID-19 crisis. Current responseThe City Corporation has connections with healthcare providers throughout the Square Mile and its surroundings, with a dedicated Joint Health and Wellbeing Strategy.33 It provides mapping of healthcare centres online, and manages pest and disease outbreaks in its natural capital. | Studies note that urban trees are at particular risk of new pathogens and pest outbreaks, since the global trade in ‘plants for planting’ is a pathway for their accidenta... | Changing seasonal conditions and global patterns will influence the spread of new and emerging diseases, while pests and invasive non-native species may also increase in... | — | The City Corporation has connections with healthcare providers throughout the Square Mile and its surroundings, with a dedicated Joint Health and Wellbeing Strategy. | |
Trade, food and infrastructureR5DescriptionWeather-related impacts, geopolitical changes and altered climate conditions are likely to negatively impact upon major infrastructure, such as the power grid and transport network, as well as disrupting food production and trade on a domestic and international scale. The City must ensure resilience to its critical infrastructure from a number of climate risks, such as flooding and overheating, as well as taking steps to secure its food supply. LocationThe London Resilience Strategy 2020 8 similarly places food infrastructure vulnerability as a key risk for the London area, and notes that food insecurity is already an issue: 21% of Londoners already live in low or very low food security. 29 Food shortages and price volatility are key threats to residents, visitors and businesses in the Square Mile. The Square Mile has negligible urban agriculture, making it heavily dependent on out-of-borough infrastructure. Current responseThe City Corporation has a thriving infrastructure of small food and drink businesses in the Square Mile – including 800 pubs and restaurants – with approximately £7.5m spent by the working population on food on a weekly basis (Buro Happold analysis, refer to Appendix B). | The London Resilience Strategy 2020 8 similarly places food infrastructure vulnerability as a key risk for the London area, and notes that food insecurity is already an i... | Weather-related impacts, geopolitical changes and altered climate conditions are likely to negatively impact upon major infrastructure, such as the power grid and transpo... | — | The City Corporation has a thriving infrastructure of small food and drink businesses in the Square Mile – including 800 pubs and restaurants – with approximately £7. |