‘We are really concerned’: Salty water creeps toward Philly drinking water intake as dry conditions persist. The Delaware River Basin Commission has a plan for situations like this, and could step up its efforts to repel the salt front if conditions worsen. Sophia Schmidt for WHYY npr.
If the drought conditions gripping a record swath of the U.S. worsen, officials in the Philadelphia region may need to take steps to protect the city’s drinking water. Dry conditions in the Philly region have caused the salt front — or the area of the Delaware River where water becomes too salty to drink — to creep north toward the intake where Philadelphia draws most of its drinking water.
The largest of Philly’s three drinking water intakes draws water from a tidal portion of the Delaware River in the far Northeast section of Philadelphia, where fresh water flowing down the river mixes with salty water from the Delaware Bay. At a certain point in this salinity gradient, the concentration of chloride could exceed an EPA guideline for how salty drinking water should be. This salt front moves based on factors including upstream rainfall, the tide cycle and, increasingly, sea level rise.
Amy Shallcross, manager of Water Resource Operations at the Delaware River Basin Commission, said:
“There’s not an issue yet, but that doesn’t mean that there won’t be an issue. We are really concerned.”
