The Delaware River Revival: Four Centuries of Historic Water Quality Change from Henry Hudson to Benjamin Franklin to JFK

Gerald J. Kauffman, Jr.

Since Henry Hudson sailed to the bay 400 years ago in August 1609, water quality in the Delaware River has changed from pristine, to polluted, to partly recovered.  Water pollution was so noticeable by 1769 that a visiting Englishman named Isaac Weld was moved to comment on the “mess” in the Delaware River at Philadelphia.  Due to pollution in the river after the American Revolution, Ben Franklin left money in his will to build a drinking water supply system in America’s largest city.  In 1940 the Interstate Commission on the Delaware River called the tidal river at Philadelphia “one of the most grossly polluted areas in the United States.”  During the Second World War, water pollution was so bad that a newly painted ship faded to the colors of the rainbow as it sailed onto the river and Navy pilots were instructed to ignore the stench of the river as they flew a mile overhead.

After the war, the urban Delaware River was one of most polluted in the world with zero oxygen levels during the summer.  During the 1950s, American shad were unable to migrate through the anoxic barrier at Philadelphia and a prominent ichthyologist lamented “a near extirpation of the species with genetic origins in the basin.”  In 1973, three years after Richard M. Nixon created the U. S. Environmental Protection Agency, a pessimistic USEPA official concluded that the Delaware Estuary would never achieve fishable uses.

The watershed came when environmental laws led to a Delaware River revival.  In 1961, Pennsylvania Governor David Lawrence convinced a reluctant JFK to sign the law forming the Delaware River Basin Commission between Delaware, New Jersey, New York, and Pennsylvania, the first ever Federal-state watershed compact.  In 1968, the DRBC was the first agency to impose load allocations on river dischargers, holding them to standards more stringent than USEPA issued years later.  In 1972, Congress led by George McGovern overrode Nixon’s veto and passed the Clean Water Act, a law that invested $1.5 billion in new wastewater plants along the Delaware River.  Phosphate detergent bans by New York in 1973 and Pennsylvania in 1990, along with a 1994 halt on manufacture prompted phosphorus declines by over 25% in many rivers.

River historian Richard C. Albert wrote in 1988 that “the cleanup of the Delaware Estuary represents one of the premier water pollution control success stories in the United States.”  By 2005, dissolved oxygen at Philadelphia exceeded 4 parts per million, the fishable water quality standard, and migratory shad and striped bass returned to the river in numbers not recorded since the late nineteenth century.  Bald eagles, protected species that rely on a fish-laden diet, returned to the cleaner waters of the Delaware River in growing numbers, even nesting in South Philadelphia at the Navy Yard in March 2007.  Historic water quality recovery occurred in the Delaware River during an environmental era that coincided with the return of migratory fish populations.

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