Resilient cities are those that can withstand, adapt to, and recover from environmental, social, and economic shocks and stresses while maintaining essential functions, structures, and identities. Resilient cities prioritize sustainable and inclusive development, leveraging their assets and resources to build and maintain physical, social, and economic resilience. This includes investing in infrastructure, social services, emergency preparedness and response, and community engagement to build strong and adaptive communities that can thrive in situations of adversity. Resilient cities aim to ensure the safety, security, and well-being of their residents while promoting a sustainable and equitable future for all.
When focusing particularly on coastal cities, these cities face a range of additional challenges that are unique to their location and geography. These transversal challenges can include, but are not limited to:
- Flooding and sea level rise: Coastal cities are at risk of flooding from rising sea levels, storm surges, and heavy rainfall. This can damage infrastructure and houses, causing economic and social disruptions;
- Coastal erosion: The constant pounding of waves can erode beaches and cliffs, threatening infrastructure and homes along the coast;
- Water quality: Coastal cities must manage the discharge of pollutants from urban and industrial activities into coastal waters, which can harm aquatic ecosystems and human health;
- Coastal ecosystems: Coastal development and pollution can also degrade coastal ecosystems, such as wetlands and coral reefs, which provide important services like storm protection, water filtration, and biodiversity;
- Climate change: Coastal cities are also at risk from the impacts of climate change, including more frequent and intense storms, heatwaves, and droughts;
- Urbanization and population growth: Coastal cities often experience rapid population growth and urbanization, which can lead to increased demand for resources, the strain on infrastructure, and social and economic inequalities;
- Infrastructure maintenance and upgrades: Coastal cities need to continually invest in their infrastructure, including seawalls, water and sewer systems, transportation networks, and public facilities to ensure their long-term resiliency;
- Salinity aggression, which leads to degradation of building materials and infrastructures: Ion-based salts in seawater can harm construction materials and structures. They lead to the degradation of steel and concrete components of bridges, pavements, and roadways, increasing the danger of failure and potential harm;
- Proper characterization of materials and robust construction design guidelines.
Addressing these challenges requires a range of approaches, including coastal zone management, infrastructure improvements, ecosystem restoration, investment in infrastructure and public services, land-use planning and zoning, and sustainable development practices that balance economic, social, and environmental objectives, with the proper engagement of distinct stakeholders and communities. A resilient coastal city must balance economic development with environmental protection and social equity while also addressing the unique challenges of its location and geography.