Terminal Moraine: Large mound or hill of looses and and gravel deposited by the leading edge of a glacier.

Tributary: A river or stream flowing into a larger river or stream.



Plan a field trip to the Somerset County Environmental Education Center to view their excellent exhibit "Secrets of the Great Swamp." It traces the history of the Great Swamp from early geological time to the various cultures that have occupied the swamp.  Call 908 766.2489 for more information.

Have students identify the boundaries of the Great Swamp watershed using the contour lines on USGS topographic maps (see Appendix 4 for ordering information).


  s 5.  The Great Swamp Watershed: Natural
     And Human History

Natural History

The Great Swamp had its beginnings hundreds of millions of years ago, when the African continent collided with North America, pushing up the land mass that is now known as the Appalachian Mountains. A portion of the Appalachian Mountain chain today forms the northwestern rim of the Great Swamp watershed. This ridge line extends from Morristown southeast through the Mendhams and into Bernardsville. The Jockey Hollow section of the Morristown National Historical Park is located along this ridge line.

Roughly 210 million years ago Africa and North America began to separate once again. The stresses created by the separating land masses eventually led to successive lava flows which created the First, Second and Third Watchung Mountains. Today, the Third Watchung Mountain forms the southwestern and southeastern rims of the basin. Long Hill Township is located along the Third Watchung Mountain.

The northeastern rim of the watershed was formed most recently. About 18,000 years ago, a segment of the Wisconsin Glacier's leading edge reached the Great Swamp watershed area and stopped. Because its melt rate was equal to the southern flow of the ice, a glacial load of rock and soil was gradually deposited along its leading edge. For about 2,500 years the glacier essentially remained in this static position, melting and advancing at the same rate. This massive glacial deposit, known as a terminal moraine, runs between Morristown, Madison, and Chatham, forming the watershed's northeastern rim.

Today, the Passaic River has its headwaters in the Great Swamp watershed. There are four major tributaries of the Passaic: the Black, Great, Loantaka, and Primrose brooks. The four brooks come together in the Great Swamp, and then join the Passaic River before it exits the watershed through the Millington Gorge.

Millington Gorge

The Passaic River forms a natural border between Bernards Twp. 
in Somerset County and Long Hill Twp. in Morris County as 
it flows through the Millington Gorge.































Plan a field trip to Morristown National Historical Park to learn more about the role this area played in the revolutionary War.  Call 973.539.2016 for more information.

Ask students to research a current land use conflict in their town or another part of the watershed. Are there any similarities with the fight to stop the jetport? See the Local Issues section of the GSWA web-site at for a summary of landuse conflicts around the watershed.






Human History

As early as 12,000 years ago, Paleo-Indians inhabited the Great Swamp basin, living in nomadic, hunter-gatherer communities. When the first Europeans arrived in the Great Swamp region in the 1600s, they encountered Native Americans such as the Lenape and Minnisink. The groups peacefully coexisted for a while; however, European diseases like smallpox and measles significantly reduced the Native American communities.

As European settlements in the area grew, demand for land increased. Many of the remaining Lenape were forced to sell their land and move west toward the Delaware River and beyond. On August 13, 1708, the New Britain Purchase, the first recorded transaction between Lenape and Europeans, was signed. Though the Lenape may have thought they were merely granting hunting and fishing rights, they actually signed away 30,000 acres to British investors for the sum of thirty pounds and assorted supplies.

During the Revolutionary War, many of the towns within the Great Swamp watershed were strategically important to the Continental Army. George Washington had soldiers build a defensive earthwork structure overlooking Morristown in May 1777, later nicknamed Fort Nonsense (due to the fact that it was never needed and many thought it was a make-work project to keep the soldiers busy). This structure and other ridge-top locations provided clear eastward views toward New York, where British troops under General Howe were quartered.

View of Ft. Nonsense

The view east today from Ft. Nonsense, 
Morristown National Historical Park.

After the war, the population of the watershed increased and land uses intensified. By the mid-1800s, over 400 individual land holdings existed throughout the watershed. Later in the 19th century, the region became popular for its numerous boarding houses and health resorts, vacation spots for those wishing a quick trip from New York. It was also a favorite retreat for wealthy New Yorkers, who built enormous homes on expansive estate properties. One stretch of Madison Avenue became known as Millionaire's Row after a 1902 New York Herald article reported that 100 millionaires lived within three miles of the Morristown green.

In 1959, the Port Authority of New York proposed to build a 10,000- acre international jetport in the Great Swamp. The Authority planned to bulldoze Long Hill and portions of Chatham, Madison, and Harding to fill in the swamp and create runways. Located within the area to be demolished were 700 homes, churches, schools, and small businesses. Outraged by the proposal, hundreds of residents banded together as the Great Swamp Committee to fight the proposed jetport.



Over the next several years, members of the committee lobbied Congress, spoke at garden clubs and Rotary functions, presented slide shows on the value of the swamp's natural habitats for birds and wildlife, and most importantly, raised funds. Within five years, the Committee had bought or been given 3,000 acres of land, which had persuaded the US Department of the Interior to accept. In 1964 the Department dedicated the area as a National Wildlife Refuge to be administered by the US Fish & Wildlife Service.

Despite the formal establishment of a National Wildlife Refuge, the Port Authority continued to move forward with its plan. Citizens fought on, and in 1966, the Refuge was designated as a "Registered National Natural Landmark." Two years later, in 1968, citizens persuaded Congress to declare 3,660 acres of the Refuge a National Wilderness Area, the first so designated within the U.S. Department of the Interior. The designation of a wilderness area meant that, among other things, motorized vehicles could not be operated anywhere within the boundaries, thus forever precluding the area from becoming a jetport!




Visit the Great Swamp National Wildlife Refuge to hike some of the trails in the Wilderness Area, or view wildlife from the obersvation areas.  Call 973.425.1222 for more information.

Vist the Great Swamp Outdoor Education Center on Southern Blvd. in Chatham to view the interpretive displays about Great Swamp wildlife.  Call 973.635.6629 for more information.



Sign at Entrance to the GS National Wildlife Refuge

Great Blue Heron

Today, a healthy population of Great Blue herons 
can be viewed during the spring at the heron rookery 
on Pleasant Plains Rd. in the Refuge.


Copyright 2000. Great Swamp Watershed Association.