Resilient Coastal Cities



What is the Resilient Coastal Cities app?




The Resilient Coastal Cities application uses cutting-edge technology to integrate real-time flood risk information from social media,  socio-economic vulnerability, ecological data, and 3-Dimensional simulations to explore opportunities

Main functions:

  • Incorporates data mined from twitter to visualize near real-time reports of flooding across the city with summary statistics for the number of people, livelihoods, and critical infrastructure potentially impacted over a selected time period
  • Allows to explore mangrove restoration opportunities and view 3-D simulations of potential, protected land, and land that can be converted to mangroves.

Photo credit: © Kevin Arnold

Who should use it?

This application was built as part of the Resilient Coastal Cities and Coalition Building Project, led by the American Red Cross and Global Disaster Preparedness Center for the Semarang City Coalition which is comprised of members of local government, local NGOs and universities, and the Semarang branch of the Indonesian Red Cross (Pelang Merah Indonesia). The broader audience includes land managers and city planners who want to prioritize nature-based adaptation and flood reduction solutions to areas where the most assets are at risk.

How does it work?

  • Real-time flood events by administrative unit.
    • Through machine learning algorithms, FloodTags, a social enterprise from the Hague, Netherlands, passively extracts flood related reports from Twitter including time, location, and most frequent words and hashtags used. The events are then validated according to additional data sources including rainfall gauges. Results are shared via the FloodTags flood response dashboard and are consumed by Coastal Resilience where the flood data are used to summarize socio-economic vulnerability to help identify mangrove restoration opportunities.
  • Peta Bencana, crowdsources reports through social media, instant messaging and other relevant applications to validate flood reports with the Semarang City government, and add details about location and water depth to those produced by FloodTags.
  • Adaptation options to reduce flood risk:
    • In partnership with Esri, TNC used information on sediment accretion rates and mangrove growth behind permeable barriers to develop 3-D visualizations showing how various restoration scenarios would look and grow over time.

What are the strengths and limitations?
  • App Strengths:
    • Social media data mining provides a near real-time picture of flood risk and is updated every hour.
    • Integrating flood risk with locally relevant social, economic, and ecological data enables users to see where floods are consistently happening over time to help prioritize recovery and preparedness efforts through nature-based adaptation.
    • The 3-D simulations allow planners and decision makers to explore the relationship between mangrove restoration and built infrastructure and can provide a conceptual vision for future implementation.
  • App Limitations:
    • The flood events are populated by both the passive harvesting of Twitter data on floods and crowd-sourced flood reports sent to Peta Bencana. These reports do not necessarily capture every single flood happening in and around Semarang.
    • The application does not include derelict aquaculture ponds that could potentially be re-purposed as mangrove forests because there is no spatial data available for these ponds.
    • The adaptation options listed are prioritized as much as possible, but further investigation into the socio-political requirements for reforesting mangroves and protecting open space are necessary before any action is undertaken.
Where is it being used?

The application was built for the Resilient Coastal Cities and Coalition Building Project in Semarang, Indonesia, and will be used by the city coalition as part of their efforts to build community resilience to floods across the city. This integrated resilience-disaster management approach is intended to provide a geospatial framework that will serve as a pilot approach to be leveraged in cities across Southeast Asia.

Who helped develop it?

The application is part of the Resilient Coastal Cities and Coalition Building Project, led by the American Red Cross and Global Disaster Preparedness Center.

The Nature Conservancy (TNC) is working with Microsoft, Esri, Flood Tags, Peta Bencana, Wetlands International, and Pelang Merah Indonesia (PMI) to apply Azure-based Artificial Intelligence (AI) and ArcGIS (G-DSVM) to a custom tool and mobile application that will demonstrate the critical role mangroves play in reducing social and economic vulnerability to flooding in Semarang, Indonesia.