Urban flood risk management through the lens of citizen science: A case study on the two city corporations’ area of Dhaka

Dhaka is one of the most densely populated cities in South Asia. In recent times, prolonged urban flooding/water logging is a recurring phenomenon and major concern in the two city corporations' areas. This study investigates how “citizen science” could help individuals, communities, and stakeholders to understand and manage the risk of current and future urban flooding, by integrating people's experience, concerns, and opinions on flood risk management into the formal framework. A questionnaire survey was conducted among 500 respondents in water logging affected wards of Dhaka. We identified that every year respondents in two city corporations experience 1–3 days of water logging, mostly during the monsoon season. Respondents were found to be aware about flooding and its associated risks and emphasised a concern about the increasing frequency of urban flooding in Dhaka over the next 10 years. Although 61.2% of the respondents were not familiar with the concept of citizen science, 42.8% of respondents expressed eagerness to become involved in any related project to promote awareness and mitigation of urban flooding issues in their communities. Key stakeholder and focus group discussions exposed that unplanned urbanisation, poor drainage system management, inappropriate waste management systems, and recent extreme rainfall events are the major perceived drivers behind urban flooding in Dhaka. Our discussions emphasised the need for integration of both modelling and geospatial techniques to build a Volunteer Geographic Information (VGI) system for the mitigation. We conclude that citizen science approach could play a significant role in tackling urban flooding risks in Dhaka.