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The Great Swamp and its Surrounding Watershed

The Great Swamp Watershed is a 55-square-mile region in Morris and Somerset Counties of the state of New Jersey, and includes portions of ten different towns.

A watershed is a geographical area all of whose streams flow into a single body of water. In the Great Swamp Watershed, five streams – the Upper Passaic River, Black Brook, Great Brook, Loantaka Brook, and Primrose Brook all flow into Great Swamp and exit as the Passaic River via Millington Gorge.

Area Map of Watershed
Area map of the Great Swamp Watershed

The large south-central green/gray shaded area is the Great Swamp National Wildlife Refuge. Note that this protected area is only a small portion of the total watershed!



Geological History
Natural History
Human History
The Future
Ten Towns
Things to See and Do