Dr Mst Farzana Rahman Zuthi is a professor in the Department of Civil Engineering at Chittagong University of Engineering and Technology (CUET). She earned her PhD in Civil Engineering from the University of Technology Sydney. Her research spans water quality, wastewater treatment, solid and plastic waste management, and environmental health risk assessment. She is currently serving as the head of the Department of Water Resources Engineering at CUET. Dr Zuthi recently spoke to Bonik Barta about the current flooding and waterlogging in Chattogram. The interview was conducted by Sabrina Shorna.

Large parts of Chattogram remain inundated after days of heavy rain. Thousands of people are stranded by floodwater and landslides have also claimed many lives. The city faces similar flooding and waterlogging almost every monsoon. To what extent does the current situation reflect the impact of climate change, and how much stems from shortcomings in disaster management?

The current situation results from both climate change and urban disaster management deficiencies. Increasingly frequent and intense rainstorms, driven by climate change, strain city drainage systems. Persistent waterlogging is also influenced by human factors including inadequate drainage infrastructure, canal encroachment and siltation, poor maintenance, uncontrolled urban development and construction on unstable hillsides. Thus, while climate change serves as a significant trigger, the severity of its impacts largely depends on urban planning, infrastructure management and disaster preparedness.

Could a more effective early warning system have reduced the loss and damage from the current disaster?

While we can’t prevent extreme weather events, we can definitely lessen their impact through effective forecasting. Having accurate rainfall predictions along with real-time alerts for floods and landslides gives authorities the tools they need to protect communities. With that information, they can evacuate those at risk, prepare emergency response teams, manage traffic, halt activities in dangerous areas and gather resources in advance.

When it comes to landslides, timely warnings can be a lifesaver. They allow people living in vulnerable hillside areas to move to safety before a slope gives away. This proactive approach can truly make a difference in saving lives and minimizing harm during such events.

How has the condition of Chattogram’s canal network contributed to its persistent waterlogging?

During visits for various purposes and research activities, I observed that many canals in Chattogram have experienced significant reductions in their effective flow capacity due to sediment accumulation, solid waste disposal, illegal encroachment and inadequate maintenance.

Canals serve as the city’s natural drainage network. When their hydraulic capacity is reduced, stormwater can’t be conveyed efficiently to downstream water bodies, resulting in prolonged waterlogging during heavy rainfall events. Therefore, restoring and maintaining the canal network should be considered a key component of urban flood management.

What is the biggest weakness in Chattogram’s current drainage system?

The main issue is the lack of a coordinated approach to urban water management. Drainage systems such as canals, drains and pumping stations need to work together, but responsibilities are split among different agencies. This leads to poor planning, coordination and maintenance. On top of that, problems like ineffective waste management and rapid urban growth have made the drainage system even less efficient.

To what extent do the technical capacity of Chattogram’s sluice gates and pumping stations match the intensity of recent rainfall?

During periods of simultaneous heavy rainfall and high tide, sluice gates often can’t discharge stormwater effectively because of elevated downstream water levels. Under such conditions, pumping stations become the primary means of drainage. If their capacity is insufficient, water accumulates rapidly in low-lying urban areas. Therefore, these systems should be periodically reassessed and upgraded using climate-resilient design standards and updated rainfall projections.

To what extent are modern data and modelling tools being used to assess flood and waterlogging risks in real-world planning?

In recent years, the use of advanced technologies has grown. But there’s still a significant gap between research and real-world application. Tools like Geographic Information Systems (GIS), remote sensing, drone surveys, LiDAR and satellite observations can greatly enhance flood forecasting, drainage planning and risk assessment. However, these technologies need to be better integrated into infrastructure design and urban planning to enable informed decision-making.

Will the engineering design of the ongoing waterlogging mitigation projects, with a combined cost of more than BDT 140 billion, strengthen Chattogram’s long-term water management?

The projects could significantly enhance urban drainage if properly designed and maintained. But successful implementation also requires regular canal maintenance, sediment removal, preventing encroachment, effective solid waste management and adapting to future climate conditions.

Where should policymakers place the greater priority: short-term (improving drainage) or long-term measures (structural reforms)?

Both short-term and long-term solutions are crucial to reducing flood and waterlogging risks in Chattogram and should be pursued together.

In the short term, we need to focus on clearing blocked drains, ensuring pumping stations operate effectively, removing waste and enhancing emergency drainage during heavy rain.

For the long term, we should prioritise restoring natural waterways, creating climate-resilient drainage systems, protecting urban retention areas and adopting a comprehensive approach to urban water management. Sustainable solutions require planning that goes beyond immediate responses.

What recommendations would you make to policymakers on water resources management?

An integrated approach to urban water resource management is essential. Elements such as canals, drains, pumping stations and flood control infrastructure should be coordinated. Regular hydraulic assessments and maintenance are crucial for operational efficiency. Preventing encroachment and improving solid waste management will enhance drainage. Utilising modern technologies, including GIS and real-time monitoring, can significantly improve planning and decision-making. Infrastructure design standards should be updated to account for future rainfall patterns and climate change, rather than relying solely on historical data. Strengthening inter-agency coordination is critical for effective urban drainage and flood management. Moreover, transitioning from reactive disaster response to a proactive, risk-based strategy is essential for fostering prevention, resilience and long-term sustainability.