Resilent City Design (DP IB Geography): Revision Note

Resilient City Design

What is urban resilience?

• Resilience is defined as:

• Urban resilience is how well the communities, businesses, population and systems in a city are able to function and be economically productive, no matter the issues faced

• Although similar to sustainability, it focuses on:

  • Chronic stresses such as water and transport infrastructure

  • Shock events such as flooding or terrorism

Why are cities vulnerable?

• The larger cities become and the higher the population densities, the more vulnerable they are

  • The UN estimates that 3 out of every 5 cities with a population over 500 000 are vulnerable to natural hazards

  • Some cities, such as Manila and Tokyo, are vulnerable to up to five natural hazards

  • There are only three of the world's megacities which are at low risk or no risk of natural hazards

• Urban areas are centres of population and economic activity

• When natural hazards affect urban areas, the effects are frequently more severe and expensive

• Climate change is increasing the vulnerability of cities due to the increase in frequency and severity of flooding, drought and tropical cyclones

• To be able to withstand these hazards, cities need to be resilient

Measuring resilience

• The Organisation for Economic Co-operation and Development (OECD) states there are four components of resilience:

  • Economic 

  • Social

  • Environmental

  • Governance

• These can be assessed using the following criteria:

Criteria to Assess Resilience

Resilient city design

• There are many ways in which resilience can be incorporated into urban planning, city and building design including:

  • Infrastructure improvements and resilience

  • Urban heat reduction

  • Energy efficiency

  • Creation of green spaces

  • Emergency preparedness

  • Flood mitigation

• In cities which are vulnerable to tectonic hazards, there are several mitigations which may be put in place, including:

  • Improved planning and building regulations

  • Earthquake-resistant building design

  • Land use zoning to ensure vital infrastructure and buildings are not in the most vulnerable areas

  • Education to make the population aware of the actions to take before, during and after an event

  • Hazard mapping to identify the most vulnerable areas

Strategies to Manage Climatic Risks in Urban Areas

• Climate change brings additional risks to urban areas

• Many cities are located on coastlines and floodplains which are high-risk locations

• Climatic risks include:

  • Flooding

  • Storms

  • Water-borne diseases

  • Heatwaves

  • Wildfires

  • Drought

Managing climatic risks

• Many cities are now integrating planning and building design to mitigate these risks 

• In Mexico City, water supply issues caused by drought mean that 40% of the population lacks access to regular water supplies

  • The city now has a goal of installing 10 000 rainwater harvesting systems each year in households across the city

• In Melbourne, Australia, there have been increases in:

  • Stormwater harvesting to irrigate parks

  • Investment in green space to provide shade and enhance biodiversity

  • Permeable surfaces to reduce flooding risk

• Many parts of The Netherlands are at risk of flooding. Rotterdam's strategies include:

  • Building design to cope with flooding and sea level rise 

  • Plans for a floating neighbourhood, which will have homes, offices, a school and a park

  • Water squares, which are areas set lower than the surroundings, can fill with and store water 

  • Increased green spaces and permeable surfaces to allow water to infiltrate

  • Working with residents to adapt housing by:

    • Moving wiring to upper floors 

    • Replacing wooden floors with more water-resistant coverings

    • Subsidising green roofs

    • Collection of rainwater

Strategies to Manage Geopolitical Risks in Urban Areas

• Geopolitics are politics which are influenced by geographical factors, including:

  • Level of development

  • Resource availability

  • Land ownership

• The main geopolitical threats to urban areas include:

  • War

  • Terrorism

  • Protests

  • Segregation of communities

  • Loss of economic power

Managing geopolitical risks

• Increased threat of terrorism and protests have led many cities to implement strategies to reduce these risks

• In London, UK, some of the strategies which have been implemented include:

  • External barriers to prevent vehicles from ramming buildings or infrastructure

  • Improved building materials which are blast-resistant

  • Better communications system

  • CCTV 

  • Increased security measures for people entering public buildings