Many of Bangladesh’s natural water resources also face contamination from geological and human pollutants. Bangladesh’s rocks contain high levels of arsenic — a poison and carcinogen. Arsenic leaches naturally into groundwater, which can contaminate irrigated crops and soils. Some 17% of the population of Bangladesh — about 29 million people — have been found to be exposed to arsenic, mostly from contaminated shallow wells that constitute the backbone of the country’s rural water supply.
Over the past few decades, Bangladesh has benefited from World Bank initiatives, in partnership with local authorities, which have added thousands of cyclone shelters and water-control structures, several thousand kilometres of dikes and hundreds of polders. As a result, 333,000 people are now better protected from tidal flooding and storm surges. More investments are needed to protect against the increasing risks posed by climate change.
Publishing hydrological data in an open-access database would be an exciting step. For now, however, the logistics, funding and politics to make on-the-ground data publicly available are likely to remain out of reach.Fortunately, satellite data can help to fill the gaps.
Satellite-based irrigation advisory systems can help by determining the volume of water actually needed by crops. One of us has helped to implement one such system in northern India and eastern Pakistan. This was developed at the University of Washington in Seattle, in partnership with the Indian Institute of Technology in Kanpur and the Pakistan Council of Research in Water Resources in Islamabad.