Identifying multiple deep aquifers in the Bengal Basin: Implications for resource management

In the Bengal Basin of Bangladesh and West Bengal (India), where arsenic (As) and salinity adversely affect groundwater in shallow aquifers (<150 m deep), consumers increasingly turn to “the deep aquifer” as a source of low‐As and low‐salinity water. We show that “the deep aquifer,” which has traditionally been regarded as a single entity, can be divided into at least eight deep aquifer units each with distinctive chemical, isotopic,...