Location and History
The Delaware River is the last major free flowing river on the east coast. Originating in the Catskill Mountains of New York, the East and West branches of the Delaware River meet in Hancock, New York and form the main stem of the river. The River flows a total of 375 miles from the Catskills to the sea. Its watershed, includes 12,765 square miles in portions of four states -- New York, New Jersey, Pennsylvania, and Delaware -- and is home to nearly 6 million people.
The Delaware flows through forested mountains, farmlands, small historic towns, suburban sprawl, urban development, industrial complexes, and extensive wetlands before reaching the Atlantic Ocean. While the River drains only 1% of the land, it supplies water to 7% of the population of the United States, approximately 20 million people, many of whom live outside the watershed. The Delaware has been called a "Servant of many masters"-- its uses include recreation, industrial plants, shipping, and drinking water.
Historical uses of the river have burdened its ecosystems. In Trenton the river once ran black with the silt of coal mines far away in the Lehigh Valley. Untreated human waste was dumped into the river, and its tributaries by scores of towns and cities. By World War II, pollution in the river was so severe, the waters were anoxic, devoid of any dissolved oxygen, from bank to bank, surface to bottom, for a 20 mile stretch in the Philadelphia-Camden area. When the shad migrating upstream swam into this barrier they either suffocated or turned back unable to reach their spawning grounds.
For 102 miles beginning at the East Branch- West Branch confluence in Hancock, the River is a major national recreation area, protected by both the Wild and Scenic River System and the National Park Service. The River is shaped by its Pocono tributaries where streams flow to join the river through dark tunnels of trees, past moss covered rocks. These include cool, swift, rocky trout streams of renown. With names like Bushkill, Broadhead, and McMichaels, their native brook trout- now all but gone- were once fished by the likes of Theodore Roosevelt and Gifford Pinchot. Many of these tributaries flow out of the high Pocono wetlands which hold, filter, and control the flow of the water downstream. The world-famous Delaware Water Gap National Recreation Area lies within this region, where one can see wintering bald eagles soaring between 1600 foot ridges. In the summer ospreys dive for food to feed their broods in nearby nests. Unfortunately Interstate 80, often crowded with commuting cars and trucks, runs through the picturesque Gap. Pike and Monroe Counties border the Delaware in the protected area of the River in Northeastern Pennsylvania. These counties are two of the fastest growing counties in the country. The problem now is protecting the land and waters around the preserves.
Wildlife in The Delaware Bay
Each May the waters along the Delaware Bay swarm with horseshoe crabs. Female horseshoe crabs lay up to a few dozen clusters of 3,000 eggs along the sandy shores of the bay. During the same period millions of migrating shorebirds, which have come 3,000 miles from South America on their way to Arctic Nesting grounds, land on this same strip of bay shore to rest and feed on the horseshoe crab eggs.
Among those migratory shorebirds are Red Knots and Sanderlings are two species in decline. The shorebirds feeding grounds are within sight of shipping channels where tankers carry some 30 million gallons of crude oil a day up to the refineries in Wilmington and Philadelphia. The extinction or survival these birds could hinge on one catastrophic oil spill.
The waters between the Trenton Falls and Wilmington were once major spawning grounds for shad and striped bass. In 1896 some 15 million pounds of shad were caught from the Delaware. During those years fisheries lined both sides of the river. Many of these places, along with wetlands and spawning tributaries, are now gone. They have been replaced by docks, wharves, industries, refineries and dredge spoils dumps.
Threats to The River
Today the greatest pollution of the River comes during storm events. The rainwater washes sediments and pollution from land surfaces into streams and storm water drains. This runoff flows tainted through countless tributaries into the Delaware River. Some runoff sources are herbicide drenched lawns; oil stained streets and parking lots; fertilized farm fields sprayed with pesticides and fortified with fertilizers; and acid mine drainage.
Another hazard to the health of the River comes from point-source pollution -- direct discharges from municipal and industrial sewage treatment plants, power plants, chemical plants, paper mills, refineries, and refracteries. Most point-source dischargers have permits issued under the Clean Water Act and the National Pollution Discharge Elimination System. These permits limit the quantities and types of pollutants permitted to be contained in the wastewater. There are 1600 permitted discharge points in the Delaware Watershed.
In many urban regions of the watershed, storm water, sewage, and industrial wastes all flow through the same system of pipes into treatment facilities. During storm events the rainwater mixes with the sewage. In many cases this overwhelms the capacity of treatment facilities, which were not designed to handle the volume. Overflow devices, called combined sewer overflow (CSO), divert the excess directly into streams. An uncontrolled source of untreated sewage, CSOs are detrimental to the water quality and pose a public health threat to recreational users of the River.
As a result of this myriad of pollutants that wind-up in the River, its fish and shellfish are contaminated with toxins, including: PCBs, chlordane, mercury, dioxin and DDT. Fish contaminated with toxics pose numerous hazards for humans. Delaware River states have all issued fish advisories recommending limited or no consumption of contaminated species. The state warnings contain some inconsistencies. Fish considered unsafe on the NJ side of the river may be considered safe on the PA side of the river. These inconsistencies led Riverkeeper to create a comprehensive Toxic Fish Alert with information gathered from Pennsylvania, New Jersey, and Delaware. The alert lists all warnings and advisories issued on both sides of the river.
Toxics are hazardous to birds of prey, such as the osprey and the peregrine falcon. These birds are high on the food chain so the are especially susceptible to the effects of biomagnification of toxics. Toxics such as DDT are believed to be responsible for the thinning of eggshells, causing lower productivity for many species of birds that are already endangered. The long banned pesticide DDT is still in the River's sediments. During dredging, or tidal periods the sediments are disturbed, and the concentrated toxics are resuspended, making them more available for uptake by aquatic organisms.
The Delaware has suffered a great many losses. It once knew sturgeon by the hundreds of thousands, unabating oyster harvests, shad, terrapins, and great flocks of waterfowl. While today nutrient pollution has been greatly reduced, the River continues to face threats of pollution and habitat degradation caused by our way of life.
Prepared by Kim Appleby, Spring 1995
To report pollution incidents and other threats,
call 1-800-8-DELAWARE