Largest tributaries
The Passaic River is a river, approximately 80 miles (130 km) long, in Northern New Jersey.
The river in its upper course flows in a highly circuitous route, meandering through the swamp lowlands between the ridge hills of rural and suburban northern New Jersey, called the Great Swamp, draining much of the northern portion of the state through its tributaries.
In its lower (southern) portion, it flows through the most urbanized and industrialized areas of the state, including along Downtown Newark. The lower river suffered from severe pollution and industrial abandonment in the 20th century. In April 2014, the U.S. Environmental Protection Agency (EPA) announced a $1.7 billion plan to remove 4.3 million cubic yards (3.3 million cubic meters) of toxic mud from the bottom of lower eight miles (13 km) of the river. It is considered one of the most polluted stretches of water in the nation, and the project is one of the largest toxic cleanups ever undertaken in the nation.
