(Above: The city of Da Nang, the majority of which is surrounded by water. To the east there is the Han River, and to the North the Da Nang Bay. Google Maps, Feb. 2nd, 2017)
The majority of the city of Da Nang is surrounded by water and it is susceptible to regular flooding and tropical typhoons. With a population of roughly one million and a growing economy, this city has a lot to lose when water rises. To meet this challenge, Da Nang became part of the Asian Cities Climate Change Resilience Network (ACCCRN) in 2009, and in the following year undertook a project that would change flood risk reduction within the city, the region, and possibly the whole country.
2010: Da Nang Begins Work on a Hydrologic-Hydraulic Model
During last decade, Da Nang experienced rapid urbanization and with it an encroachment on natural flood plains. At the same time, the city’s economy was flourishing and land became more valuable. City officials recognized that the issue of flooding needed to be addressed more thoroughly, and in 2010 the Da Nang Department of Construction submitted a proposal to the Rockefeller Foundation’s ACCCRN program for support to build a comprehensive flood model. The grant was awarded and the city began work. The goal was to construct a connected hydrologic-hydraulic model for Da Nang that took into consideration potential impacts of climate change and urban development. This model would allow the Department of Construction to examine the interaction between proposed development plans and flooding, both in 2010 and future projections that took into account the impacts of climate change.
For the model to be successful the city’s Department of Agriculture and Rural Development (DARD), and the Department of Natural Resources and Environment (DONRE) would have to cooperate with the Department of Construction. These departments had river system and surface runoff models that need to be integrated into the new model.
However, these departments were not accustomed to working together. Each department had their own technical languages, which made inter-departmental communication very difficult. The above departments did not see how the new model would directly benefit them, and thus were not proactive in working on the project.
An inability to communicate became one of the biggest hurdles in creating a comprehensive flood model. Progress was slow at first. But the project persisted, and with work, time, and patience, the dynamic between the three departments shifted in a positive way. This was a tipping-point towards success as each department put more effort into the project. As this happened, the departments began to learn each other’s technical languages, and could finally understand one another. With this shared language, the ‘Hydrology and Urban Development Simulation Model’ (HUDSIM) was completed and is still used today.
The HUDSIM is a powerful tool and is used in Da Nang to help reduce the risks of flooding. This modeling tool was not the only ‘fruit’ of this project, however: bringing three city departments together to create a process of collaboration and shared language was in itself an act of resilience building. The three departments needed to start working together to increase general resilience within the city, and collaborating on the HUDSIM provided a reason to begin the relationship.
2016: Replicating the Process of Resilience Building on a Larger Scale
City-wide cooperation on flood risk reduction has been beneficial for Da Nang, and city officials now recognize that the process must be expanded to include the entire flood plane. This involves cooperation with their neighboring jurisdiction, Quang Nam. Through a grant from the Global Resilience Partnership (GRP) Da Nang and Quang Nam are beginning to replicate the resilience-building–through-flood-modeling process. This project began in 2016 and is attracting national attention as the government of Vietnam looks to this regional effort as an example for other river basins in the country.
ISET has been involved in resilience building in the city of Da Nang since 2010 and was a key facilitator in the HUDSIM effort. Our Vietnam team will be crucial players in the future efforts of Da Nang and Quang Nam to create a basin-wide model.