More than 2 million residents of Zimbabwe’s capital on Tuesday were left without drinking water after authorities shut down the main treatment plant, further worsening a region beset by economic instability and drought. Tuesday’s shutoff comes as the country is still reeling from the worst cholera outbreak in a decade. Meanwhile, water levels in polluted reservoirs have dropped because of drought. Officials in Harare have struggled to raise the necessary $2.7 million in foreign currency needed to import water treatment chemicals. City Council spokesman Michael Chideme said everyone living in Harare is affected and that some residents have turned to...