Map zeroes in on pollution in Delaware River watershed

A new interactive map shows threats, old and new, to vital water source. It underlines challenges that remain for river that ‘has come back from the brink’

Credit: Steve Guttman/Flickr CC
Delaware River
It is the longest free-flowing river east of the Mississippi, the source of drinking water for more than 15 million people and a dynamic natural resource providing billions of dollars in economic activity.

But the Delaware River Watershed faces numerous threats from both longstanding and persistent pollution. A new interactive map developed by Environment New Jersey Research & Policy Center aims to pinpoint those challenges and help identify ways to address them.

“The Delaware River is a vital source of water for drinking, wildlife, and recreation,’’ said John Rumpier, clean-water program director at Environment America Research & Policy Center. “But as our map shows, we still have work to do to ensure that the watershed is — and remains — as clean as we want it to be.’’

Map of Delaware River Basin showing sites of industrial pollution and hazardous waste: Click to expand/collapse
The challenges, identified in the interactive map, are fourfold, perhaps the most troublesome involving urban runoff fouling the Delaware River and its 216 tributaries. The map also looks at the pollution threats from hundreds of industrial facilities discharging wastewater into the basin, and thousands of hazardous-waste sites in the region, including more than 100 Superfund sites.

While investments have led to improvements in water quality, more than 250 sewage-treatment plants remain discharging effluent in the watershed. Many are antiquated, still putting much pollution into the river and other waters, according to Rumpier. At another 350 locations, combined sewer-overflow systems carry stormwater and raw sewage into waterways during times of heavy rain.

Finally, the map identifies the legacy of the region’s reliance on fossil fuels — more than 150 active and abandoned coal mines in eastern Pennsylvania and the millions of barrels of oil shipped on the Delaware each year.

Go to the interactive map of pollution in the Delaware River Watershed

‘Pollution risks waiting to happen’

The more recent drilling of thousands of wells for natural gas in the Marcellus Shale formation and the rapid expansion of pipelines to bring the fuel to consumers is laid out in the map. “These are pollution risks waiting to happen,’’ Rumpier said.

“This interactive map shows that, when it comes to water quality in the Delaware River, everything is connected,’’ said Tony Dutzik, senior policy analyst at the Frontier Group, which played a major role in developing the map. “The map provides residents of the basin with new insights about water quality challenges and how they can be solved.’’

The product of a year-and-a-half effort, the map draws on more than 5,000 data points from over a dozen sources to major pollution threats in the basin. But more information is needed, according to Rumpier and others.

There are large factory farms with large numbers of animals producing vast quantities of manure. Little is known about the extent of pharmaceuticals and household chemicals that wind up in waterways.

Impaired waters in Delaware River Basin: Click to expand/collapse
“Runoff pollution is one of the most challenging and vexing problems,’’ said Rumpier, suggesting it is one area deserving of more attention.

That point is amply demonstrated in the map’s detailing of impaired waters within the watershed — those failing to achieve water-quality standards for such things as swimming or fishing; much of the area surrounding Philadelphia and central Jersey is covered in red, the map’s designation for impaired waters.

“The Delaware River watershed has come back from the brink over the last half century,’’ said Doug O’Malley, director of Environment New Jersey. “This map drives a visual to get the public and advocates more engaged in the threats facing our waterways.’’

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