Indonesia: Enhancing urban flood resilience investments with healthy and green multi-functional public spaces

By Muhammad Halik Rizki and Jian Vun

While urbanization opens doors for various benefits—such as increased prosperity, more livable cities, and a more inclusive society—it also bears certain risks. Rapid urban expansion, for instance, exposes assets and people to increasing flood hazards. Urban development can result in the loss of permeable (or pervious) surfaces, decreasing the ability of water to seep into the ground. As a result, stormwater runoff, peak discharge, and sedimentation all increase, leading to urban floods like those that affect Tuti, Shyntia, and Edi as can be seen in the video. As Indonesian cities grow, others across the country will be at increased risk from urban flooding.

To mitigate these hazards, cities need a strategic mix of “grey” and “green” infrastructure investments. Nature-based and green infrastructure solutions can help increase a city’s resilience while providing co-benefits such as environmental sustainability and eco-tourism. Indonesia is already exploring how these water-sensitive approaches could be implemented in Bogor City.

COVID-19 has demonstrated additional reasons why such efforts to mitigate urban floods are vital. Concurrent disasters may exacerbate the impact and spread of diseases, further straining emergency services and public health resources. Disaster response has been complicated by the need to integrate public health measures such as physical distancing and appropriate hygiene practices in evacuation and response procedures, and maintaining health protocols in flood shelters.

Therefore, it is critical that we enhance the design of flood resilience investments – while incorporating public health considerations.

In addition to mitigating disaster risk, urban flood resilience interventions offer broader co-benefits for surrounding communities’ physical and mental health. Access to public green spaces for physical exercise, for instance, can help strengthen the immune system. Multifunctional green infrastructure designed to mitigate floods and provide urban public spaces—built in various spatial configurations can provide diverse opportunities for recreation. For instance, exercise tracks along rivers and creek corridors, and open green spaces can serve as sites for group sport and activities.

Planning tools can help officials maintain and protect existing green infrastructure and develop new projects. Here are some key considerations when developing multi-functional green spaces :

• In many cities, land is a scarce resource, so it’s important to prioritize the development of existing landscapes that already provide flood mitigation or control. Existing open spaces can be designed or retrofitted to be multifunctional for flood management, emergency measures, and recreation.
• How much multi-functional green space does a city need? Ideally, green space should be accessible to the community and proportional to the number of population. For example, some international standards recommend that people should have access to green space within 15 minutes’ walk.  In Indonesia, the Public Works and Housing Minister Regulation suggests an allocation of 1m2 per capita in each neighborhood (RT). They can form an interconnected green space system with various types and scales of spaces.
• Widen footpaths and reduce obstacles such as planters to allow for physical distancing between pedestrians, vehicles, and cyclists. Wherever possible, provide separate entry and exit points.
• Carefully select plant species that are capable of withstanding periods of flooding, pollution, and drought dependent on the local context (e.g., lemon grass, vetiver grass, and lilyturf is suitable for bioretention systems in the tropics).
• Multifunctional parks can also function as temporary storage of floodwater. But to maintain a park’s capacity to absorb floodwater, it’s critical to release the water at a controlled discharge rate. In addition to improving water quality, stored water can be used to irrigate public facilities, such as schools and university campuses.
• Perform regular maintenance. Maintenance helps municipalities sustain the aesthetics and performance of their public spaces, and avoid the high costs associated with restoration.

By collaborating across the disciplines of urban planning, public policy, and disaster risk management, and by integrating grey-green infrastructure into the urban landscape, together we can create robust cities and healthier communities. 

The World Bank is supporting the government of Indonesia to establish a national urban flood resilience program, including through the proposed National Urban Flood Resilience Project and technical assistance financed by the Global Facility for Disaster Reduction and Recovery (GFDRR) and the Indonesia Sustainable Urbanization Multi-Donor Trust Fund (IDSUN). Outcomes of the national urban flood resilience program would reap co-benefits, including the development of healthy and green public spaces, that would bolster overall community and public health.