The challenge
Vientiane capital city and Pakxan city are two of the most flood-prone areas in Lao PDR. Most investment in flood protection infrastructure has focussed on levees to protect against fluvial flooding from the Mekong River. Urban drainage systems have had low investment, with existing systems having insufficient capacity to manage peak pluvial events. This TA project uses new modelling, risk studies and economic assessments to develop a strategic investment plan for urban flood risk.
Our work
JBP worked alongside our partners in JBA Global Resiliance, the World Bank , in-country partners and the Loas PDR government departments (DoW, MONRE) to deliver the strategic flood investment plan. We used ten risk metrics, including damage to properties (contents and infrastructure), disruption of traffic, health risk, disruption of business activities, environmental impact, agricultural impacts, aquaculture impacts, and airport impacts. This was supported through new flood damages survey of commercial properties throughout Vientiane. Flood damages were assessed using risk metrics (hydraulic hazard categories vs infrastructure/landuse type) and economics, the latter including depth-damages, associated intangible damages, which were computed into AAD/AAL and PML. Comparative existing case vs urban flood mitigation options were assessed to estimate benefit-cost ratios (BCR) and Economic Internal Rate of Return (EIRR).
