Extreme rainfall has become the new normal for countries across East Asia, which is why South Korea has, in the past few years, been rolling out “digital twin” technology to assist with its adaptation efforts.
The idea is to build a virtual model that can simulate flood paths and predict inundation areas in 3D space, allowing decisionmakers to see how flooding might unfold before it happens.
It represents a fundamental shift in disaster management thinking, from post-disaster response to pre-disaster forecasting, and from experience-based judgement to data-driven decisionmaking. As a nation prone to climate vulnerabilities, Taiwan has much to learn from this transition.
The core concept of the digital twin is to build a virtual replica of the environment and continuously update it with real-time sensor data to reflect dynamic real-world changes. In flood prevention, this means integrating large-scale spatial data such as river terrain, drainage systems, underground infrastructure, building distribution and soil permeability into a 3D model. Combined with radar rainfall data, water level sensors and weather forecasts, the system can simulate potential flood pathways and inundation depths hours before heavy rain arrives.
Taiwan is not without a foundation to build on. The National Science and Technology Center for Disaster Reduction has accumulated rich flood-risk map resources, while local governments have built water-level monitoring stations and early warning systems, with some working with research institutions to develop flood forecasting models.
However, those efforts continue to run up against the same bottlenecks: Data are scattered across agencies with inconsistent standards; simulation results are difficult to visualize in real time as decisionmaking tools; local disaster management staff lack sufficient training in digital tools; and cross-agency data integration has not been institutionalized.
The cost of this is clear. Whenever a typhoon passes, the most difficult decisions for local governments are rarely whether to evacuate, but when to evacuate, which areas to evacuate and how to allocate resources.
Under the current system, such judgements rely heavily on the experience and intuition of local leaders and disaster personnel, but lack systematic simulation support. The value of digital twin technology lies in transforming these judgements from matters of individual intuition into systematic processes that are repeatable, verifiable and can be rehearsed in advance.
Policy implementation requires several key prerequisites to be in place simultaneously.
First, a nationally unified spatial data governance framework for disaster prevention must be established. At present, geographic data maintained by the Ministry of the Interior, the Water Resources Agency, the Central Weather Administration and local governments vary in standards, update frequency and accessibility.
Without solving data interoperability, even the most advanced simulation platform would produce inaccurate results due to poor data quality. The government should designate a single authority to coordinate data standards and cross-agency integration.
Second, digital twin flood prevention technologies should be incorporated into statutory spatial planning tools. Their greatest value lies in simulating the consequences of potential development projects for flood risks. If environmental impact assessments for land development projects are required to include flood risk analysis based on digital twin simulations, it would pose a fundamental challenge to Taiwan’s tendency of reclaiming and developing low-lying areas. This would allow data — not development pressure — to guide decisionmaking.
Third, local government capacity in digital disaster prevention must be strengthened. In South Korea, investment in local disaster personnel training was carried out alongside platform development, which helped ensure that central tools could actually be used at the local level. In Taiwan, where local government personnel resources and budgets can differ greatly between regions, central technological investments might not actually translate into real disaster prevention capabilities without systemic capacity-building programs
South Korea has accelerated technological investment as a result of the disasters it has experienced. Taiwan’s geographic and climatic conditions are even more challenging, with typhoons, earthquakes, torrential rain and landslides often occurring in combination and requiring higher levels of system resilience.
The simulation capability of digital twins represents only one side of the coin; what makes it useful as a technology is the broader institutional architecture of data governance, regulatory frameworks and talent development. Before the next flood, Taiwan needs an integrated platform where all data can be integrated across the same virtual space.
Roger Chen is a legal specialist for a technology corporation.
Translated by Gilda Knox Streader
