Pushed salt line is brought on by recent drought conditions in US north-east and rising sea levels linked to climate crisis

Salty ocean water is creeping up the Delaware River, the source for much of the drinking water for Philadelphia and millions of others, brought on by drought conditions and sea level rise, and prompting officials to tap reservoirs to push the un-potable tide back downstream.

Officials say drinking water isn’t imminently at risk, but they’re monitoring the effects of the drought on the river and studying options for the future in case further droughts sap the area, amid the climate crisis.