Despite progress in early warning systems for floods, there is still need for improvement to better protect the population. Understanding the causes and consequences of flooding is essential in assessing the full extent of flood-related disasters.
Flooding in Bangladesh has led to substantial loss of life and mass displacement. For instance, the 2020 floods impacted over 5 million people and forced hundreds of thousands to leave their homes. The agricultural sector, the backbone of the country's economy, faces severe repercussions from floods, including crop destruction, food shortages, and economic losses. In 2017, nearly 700,000 hectares of crops were lost due to floods. Regular flooding also disrupts trade, transport, and economic activities, with small rural businesses suffering the most, leading to prolonged economic challenges.
In Bangladesh, two main approaches are followed for flood mitigation: Structural measures and non-structural measures. Structural measures involve the development of embankments, dams, flood shelters, and drainage systems. Non-structural measures include the establishment of advanced flood forecasting and early warning systems, along with community-based disaster management and climate change adaptation programs.
Learning from others
Drawing on global experiences is always beneficial for establishing a strategic course of action. Nations like China and Japan have effectively used satellite-based remote sensing to monitor weather patterns and water levels in real time. The China Meteorological Administration (CMA) relies on satellites such as Fengyun to track weather systems and forecast heavy rainfall, which is vital for issuing early flood warnings. In addition, they have deployed networks of IoT-enabled sensors in rivers, reservoirs, and urban areas to oversee water levels and precipitation.
South Korea’s National Institute of Meteorological Sciences has devised advanced models that integrate real-time data from river basins to enhance the precision of flood predictions. Moreover, in areas with limited access to advanced technology, community-based monitoring systems are crucial. In Vietnam, for instance, local communities are trained to monitor river levels and rainfall, and they play a crucial role in disseminating early warnings.
Furthermore, collaborative measures at a regional level are important. The Mekong River Commission (MRC), which comprises Cambodia, Laos, Thailand, and Vietnam, operates a regional flood forecasting centre that issues early warnings based on data from all member countries. This collaborative approach ensures that downstream countries receive timely warnings, reducing the risk of cross-border flood disasters.
Integrating advanced remote sensing technologies can significantly enhance Bangladesh's flood early warning system (EWS) by providing real-time data on rainfall, river levels, and land surface conditions for flood forecasting. Deploying Internet of Things (IoT) sensors in critical areas can also offer real-time data on river water levels, rainfall intensity, and soil moisture. This data, combined with big data analytics, can help identify patterns and predict flood events more accurately. Additionally, AI and machine learning can be used to enhance predictive models by analyzing large datasets and historical flood data, ultimately improving the accuracy of flood forecasts and providing earlier, more reliable warnings.
Drawing on global experiences is always beneficial for establishing a strategic course of action
Having the right infrastructure
Improving the infrastructure for data collection and communication is important. Bangladesh's network of hydro meteorological stations, responsible for gathering data on rainfall, temperature, and river levels, requires expansion and modernization. The installation of additional automated weather stations and river gauges, particularly in remote and upstream areas, will enhance data availability and reliability. Besides, efficient and rapid data communication networks are also vital for transmitting information from remote sensors to central forecasting agencies. Upgrading communication infrastructure, especially in rural and flood-prone areas, will guarantee the swift relay of critical data.
It is important to know that we receive information on river water levels from upstream countries like India, but we lack information on water management or regulation, such as the operations of dams. This poses a significant challenge. It is crucial to establish a mechanism for exchanging such information through dialogue with India.
The implementation of a Common Alerting Protocol (CAP) could be advantageous. If this system is put in place, it would enable all relevant agencies, including grassroots organizations, to receive disaster warnings instantly through various media channels. Currently, we issue warnings at the national level, and then the media disseminates the information. This approach is effective for seasonal floods, where we have a lead time of seven to 10 days.
However, for flash floods, we often only get information about the severity of the situation a few hours in advance. Implementing CAP within the country would ensure that warnings are disseminated almost immediately everywhere. Whether it's through television or other media scrolls, or directly to the mobile phones of field-level disaster workers, the message would be conveyed rapidly. To achieve this, an application or management system needs to be developed, and all disaster management-related agencies must collaborate on this effort.
Investing in resilient infrastructure such as embankments, flood shelters, and drainage systems is also a major way to mitigate the impact of floods. Furthermore, integrating these infrastructures with EWS, such as automated gates in embankments that respond to flood warnings, can help effectively manage floodwaters.
Training local volunteers to monitor river levels and rainfall, and report data to central authorities can complement technological systems. These volunteers can also serve as local disseminators of early warnings, ensuring that information reaches the most vulnerable populations. Moreover, training and equipping local disaster management committees can ensure a swift and coordinated response when flood warnings are issued.
Additionally, enhancing regional cooperation is one of the most crucial measures. Given that Bangladesh's flood dynamics are closely tied to upstream activities in neighbouring countries, enhancing regional cooperation is crucial. Strengthening transboundary water management agreements with India, Nepal, and Bhutan can improve data sharing and joint flood forecasting efforts.
Flooding in Bangladesh is complex. While the country has made significant progress in flood management and disaster preparedness, the increasing frequency and intensity of floods due to climate change present significant challenges. A comprehensive, multi-faceted approach that combines structural and non-structural measures, along with strong community involvement and international support, is crucial for mitigating the impact of floods.
Dr Mohammad Kamrul Hasan is a Public Administration Researcher and Practitioner. [email protected].
