Hatfield Swamp is a fresh water

wetland A wetland is a distinct ecosystem that is flooded or saturated by water, either permanently (for years or decades) or seasonally (for weeks or months). Flooding results in oxygen-free (anoxic) processes prevailing, especially in the soils. The ...

area in the US state of

New Jersey New Jersey is a state in the Mid-Atlantic and Northeastern regions of the United States. It is bordered on the north and east by the state of New York; on the east, southeast, and south by the Atlantic Ocean; on the west by the Delaware ...

, forming what might be considered the "second bank" of the

Passaic River Passaic River ( ) is a river, approximately 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, ...

between

Morris Morris may refer to: Places Australia *St Morris, South Australia, place in South Australia Canada * Morris Township, Ontario, now part of the municipality of Morris-Turnberry * Rural Municipality of Morris, Manitoba ** Morris, Manitob ...

and

Essex Essex () is a county in the East of England. One of the home counties, it borders Suffolk and Cambridgeshire to the north, the North Sea to the east, Hertfordshire to the west, Kent across the estuary of the River Thames to the south, and G ...

counties.

Geology

During the late

Triassic The Triassic ( ) is a geologic period and system which spans 50.6 million years from the end of the Permian Period 251.902 million years ago ( Mya), to the beginning of the Jurassic Period 201.36 Mya. The Triassic is the first and shortest period ...

and early

Jurassic The Jurassic ( ) is a Geological period, geologic period and System (stratigraphy), stratigraphic system that spanned from the end of the Triassic Period million years ago (Mya) to the beginning of the Cretaceous Period, approximately Mya. The J ...

periods, when the North American plate separated from the African plate, an aborted rift system was created. The resulting rift valley, known as the

Newark Basin The Newark Basin is a sediment-filled rift basin located mainly in northern New Jersey but also stretching into south-eastern Pennsylvania and southern New York. It is part of the system of Eastern North America Rift Basins. Geology Approximatel ...

, was filled with alternating layers of

red bed Red beds (or redbeds) are sedimentary rocks, typically consisting of sandstone, siltstone, and shale, that are predominantly red in color due to the presence of ferric oxides. Frequently, these red-colored sedimentary strata locally contain th ...

sediment and

flood basalt A flood basalt (or plateau basalt) is the result of a giant volcanic eruption or series of eruptions that covers large stretches of land or the ocean floor with basalt lava. Many flood basalts have been attributed to the onset of a hotspot reach ...

s. Over millions of years, the rift valley was faulted, tilted, and eroded, until the edges of the hard flood basalt layers formed ridges. Prior to 20,000 years before the present, an ancestral

flowed through a gap in these ridges. This changed when the

Wisconsin Glacier The Wisconsin Glacial Episode, also called the Wisconsin glaciation, was the most recent glacial period of the North American ice sheet complex. This advance included the Cordilleran Ice Sheet, which nucleated in the northern North American Cord ...

, a massive continental ice sheet which formed during the last ice age, advanced on the region and permanently plugged the gap with glacial rubble. As the glacier eventually melted back, water pooled behind the ridges (known today as the

Watchung Mountains The Watchung Mountains (once called the Blue Hills) are a group of three long low ridges of volcanic origin, between high, lying parallel to each other in northern New Jersey in the United States. The name is derived from the American Native Lena ...

), forming

Glacial Lake Passaic Lake Passaic was a prehistoric proglacial lake that existed in northern New Jersey in the United States at the end of the last ice age approximately 19,000–14,000 years ago.Stanford, Scott D. “Glacial Lake Passaic.” ''Unearthing New Jerse ...

. After thousands of years, the lake drained leaving behind many swamps with various hardwood trees struggling to take hold, including the Hatfield Swamp.

Geography

The Whippany River flows into the Rockaway River, at the western end of the swamp. The Rockaway River travels a short distance and then flows into the Passaic River near the center of the swamp. The USGS gaging station is downstream of the Rockaway River confluence. At this point the Passaic River drainage is three hundred forty nine square miles. This includes the Rockaway River drainage of one hundred twenty five square miles and the Whippany River drainage of sixty nine square miles. The area is from above sea level to . Latitude 40.85 N and Longitude 74.32 W The area of Hatfield Swamp is approximately , located in northern New Jersey.

History

The swamp is named for Cornelius Hetfield who owned and operated a mill sometime before the

American Revolution The American Revolution was an ideological and political revolution that occurred in British America between 1765 and 1791. The Americans in the Thirteen Colonies formed independent states that defeated the British in the American Revolut ...

. During the struggle, the properties of Hetfield, an acknowledged

Loyalist Loyalism, in the United Kingdom, its overseas territories and its former colonies, refers to the allegiance to the British crown or the United Kingdom. In North America, the most common usage of the term refers to loyalty to the British Cro ...

, were confiscated and sold to Cyrus Crane. After the death of family member Herbert Crane in the 1960s, the mill was dismantled and moved to

Allaire State Park Allaire State Park is a park located in Howell and in Wall Township in Monmouth County, New Jersey, United States, near the borough of Farmingdale, operated and maintained by the New Jersey Division of Parks and Forestry and is part of the New ...

in Monmouth County, New Jersey.

Flora and fauna

The Hatfield Swamp floods several times a year, from heavy rain, snow melt in spring, or hurricanes passing through the area. The area is the joining point of three rivers. Due to the flooding, this makes it a difficult place to live for mammals such as deer, raccoons, possums, skunks and fox to live. Most of these animals live on the fringes of the swamp where the ground is higher. Muskrats are low in population in the swamp due to several factors. The first is the flooding of the area which fills bank dens with water. The second is the lack of plant foods that the muskrats eat. The third is water pollution, as the three rivers that were once highly polluted has gotten better, however pollutants remain in the soil and water. Waterfowl that pass through the area in the autumn stop and rest in the swamp before proceeding south. Fish that inhabit the Rockaway River and Whippany River are carp and catfish. The area has a northern deciduous forest consisting of various oaks, maples, sweet gum, and elm. Most trees are from six to ten inches (254 mm), with some going to twenty inches. Due to the constant flooding makes it difficult for hardwood trees to grow.

Hiking

The wetlands, which help facilitate hiking through their flatness, are a part of

West Essex Park The Essex County Park System comprises the county-run parks of Essex County, New Jersey. The Essex County Department of Parks, Recreation and Cultural Affairs is in charge of the upkeep and preservation of the parks, reservations and a number ...

, and there are a number of trails open for public

hiking Hiking is a long, vigorous walk, usually on trails or footpaths in the countryside. Walking for pleasure developed in Europe during the eighteenth century.AMATO, JOSEPH A. "Mind over Foot: Romantic Walking and Rambling." In ''On Foot: A Histor ...

. Both the Essex County Chapter of the

Sierra Club The Sierra Club is an environmental organization with chapters in all 50 United States, Washington D.C., and Puerto Rico. The club was founded on May 28, 1892, in San Francisco, California, by Scottish-American preservationist John Muir, who be ...

and the New Jersey

Audubon Society The National Audubon Society (Audubon; ) is an American non-profit environmental organization dedicated to conservation of birds and their habitats. Located in the United States and incorporated in 1905, Audubon is one of the oldest of such organ ...

lead trips within the swamp throughout the year, while the Essex County Environmental Center provides information regarding such trips.

External links

Birding at Hatfield Swamp

USGS topographic map
{{coord, 40.8408, -74.3283, region:US-NJ_type:waterbody, display=title Landforms of Essex County, New Jersey Landforms of Morris County, New Jersey Passaic River Swamps of New Jersey Watchung Mountains