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Hackensack Meadowlands, New Jersey, Biodiversity


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Hydrology

The Hackensack River Basin extends 55 km (34 miles) from its source at Haverstraw, New York, to its confluence with Newark Bay, and drains an area of 488 square kilometers (188.3 square miles) (NJTA 1986). The Hackensack Meadowlands contain 3,400 ha (8,450 acres) of tidal saline, brackish, and freshwater wetlands in addition to limited, mostly artificial, uplands located along the Hackensack River. There are 5.6 km (3.5 miles) of maintained (dredged) shipping channel 90 to 150 meters (300 to 500 feet) wide and 9.0 meters (30 feet) deep. From Little Ferry to Hackensack, there is a 3.3 meter (11 feet) deep navigation channel. Between the dredged reaches the river is naturally 6.5 meters (21 feet) deep on average (Day et al. 1999). The major tributaries to the mainstem of the Hackensack River in the Meadowlands are Losen Slote, Moonachie Creek, Berry’s Creek, Kingsland Creek, and Sawmill Creek on the western bank, and Penhorn Creek, Mill Creek, Cromakill Creek, and Bellman’s Creek on the eastern bank.


Mean tidal range is 1.59 meters (5.2 feet) at Kearny Point near the mouth of the river (NOAA, fide Meadowlands Environmental Research Institute [MERI] ) and 0.5 meter (1.6 feet) at Little Ferry (Day et al. 1999) near the upstream limit of the tides. The Hackensack River connects with Newark Bay just north and east of where the Passaic River empties into the Bay. Tidal waters reach the Hackensack River from Newark Bay, which receives tidal fluxes from the Arthur Kill and from New York Bay via the Kill van Kull. The Hackensack Meadowlands is a somewhat atypical estuary in that its connection to marine waters is through a constricted opening at the northern portion of Newark Bay and another constricted opening where Newark Bay debouches into New York Harbor, unlike a more typical estuary in which a wide river mouth opens directly into the ocean (J. Ehrenfeld, Rutgers University, personal communication to EK and KM, 2001).
The present hydrologic patterns are the result of sea level rise and climatic changes as well as extensive anthropogenic changes to tidal circulation caused by the building of dikes, tide gates, dams, and road beds and the subsequent breaching of water control structures in some places. From the 1920s to the 1950s, ditches and flap gates (tide gates) were build extensively in the Meadowlands. Perhaps the most notable hydrologic feature of the Hackensack Meadowlands is the loss of creek morphology and the morphology of creek networks (i.e., loss of dendritic drainage patterns) that occurred from centuries of ditching and draining (J. Ehrenfeld, Rutgers University, personal communication to EK and KM, 2001). Furthermore, these structures drained fresh water from many areas and prevented salt water intrusion. Many drained areas were subsequently filled and developed, resulting in loss of flood storage capacity. Drainage structures for mosquito control were not adequate to prevent flooding of developed areas. In “upstream” areas, e.g. Teterboro, flooding from rain is a problem, whereas in “downstream” areas estuarine storm surges are more of a problem. The U.S. Army Corps of Engineers plans to address flooding problems by enlarging existing ditches, repairing (tightening) leaky tide gates, improving existing pump stations, and installing new pumps to allow more pumping of stormwater discharge over the tide gates (Kerry Anne Donohue, personal communication to KM, 2001). USACOE is developing a hydraulic model of the Hackensack River to address questions about flooding (H. Wine, statement at USFWS workshop, 31 October 2001; MERI, personal communication to EK, 2002).

Water Quality and Air Quality

Salinity in the Hackensack River ranges from 0 to 16 ppt (parts-per-thousand). The reach of the river from the mouth to Cromakill Creek is a moderate salinity (mesohaline) zone supporting both marine and estuarine invertebrates, fishes, and turtles. The river above Cromakill Creek to just upriver of Hackensack is a low salinity (oligohaline) zone supporting both estuarine and freshwater invertebrates, fish, and turtles (Day et al. 1999). Reduction of freshwater discharge below the Oradell Dam, coupled with inputs of treated sewage effluent, caused the upper reach of the Hackensack River estuary to be more brackish (John Quinn, NJMC, personal communication to EK, 2001). Salinity is generally highest in late summer and fall and lowest in spring (Kraus and Bragin 1988).


Conditions within the estuary seem to have improved since the early 1970s as evidenced by recovery of aquatic biota and birds in the area (Crawford et al. 1994). Although environmental legislation (e.g., the Federal Clean Water Act) has greatly decreased the amounts of chemicals released directly into rivers in the region, there remain many point and non-point source inputs of many pollutants into the Meadowlands (Crawford et al. 1994, Huntley et al. 1995). Furthermore, because this is a tidal system, pollutants entering Newark Bay from the heavily polluted Passaic River, Arthur Kill, and New York Bay may be transported “upstream” into the Hackensack River and its marshes.
Pollution of the marshes, waterways, and upland areas in the Meadowlands represents the lingering consequences of past as well as present-day activities. There are reported to be about 50-60 active industrial discharges (MERI, personal communication to EK, 2002), 3 power generating plants, 7 sewage treatment plants, 32 combined sewer outflows, and 12 emergency overflows within the Meadowlands District (Day et al. 1999). MERI (personal communication to EK 2002) disagrees with some of the Day et al. numbers cited in this paragraph, and we have not been able to confirm the data independently. As of 2000, the U.S. Environmental Protection Agency had identified 7 National Priorities List (Superfund) sites within about 3 kilometers (2 miles) of the Meadowlands proper (U.S. Fish and Wildlife Service, New Jersey Field Office, map dated 2001).
The Keegan landfill, now inactive, still leaches about 246,000 liters (65,000 gallons) of contaminated liquids per day into Kearny Marsh (Quinn 1997). The EPA has documented the presence of mercury, lead, chromium and polychlorinated biphenyls (PcBs) at Kearny Marsh and motor oils and heavy metals join the list at other sites. In total, some 1.4 million liters (375,000 gallons) of liquid leachate per acre of Meadowlands landfills flow into the Hackensack and Passaic Rivers each year (Quinn 1997). Given the large number of petroleum refinery and storage facilities, chemical manufacturers, combined sewer overflows, sewage treatment facilities, and confirmed or suspected hazardous waste sites located within the Meadowlands and its surroundings, it is not surprising that the area is intensely affected by chemical pollution. What is striking is that the Meadowlands continue to support a high level of biological diversity and abundance.
Accidental petroleum and chemical spills occur in the Hackensack River periodically (Gunster et al. 1993). Heavy metals such as lead, mercury, and zinc, as well as industrial chemicals including PCBs, polycyclic aromatic hydrocarbons (PAHs), petroleum hydrocarbons, and DDT metabolites, remain in the soils, submerged sediments, water column, and aquatic biota of the Hackensack Meadowlands, often at levels considered toxic to aquatic organisms by federal (NOAA) standards (Bonnevie et al. 1993, Crawford et al. 1994, Gillis et al. 1995, Huntley et al. 1993, 1995, HMDC 1997, 2002, Durell and Lizotte 1998). The highest concentration of mercury in the major tributaries of Newark Bay was found in the Hackensack River in the Meadowlands and is attributed to a chemical facility located on Berry’s Creek (Iannuzzi and Wenning 1995). In the Berry’s Creek area, mercury concentrations were 3.6-262 ppm dry weight in the upper 10 cm (4 inches) of soil, with only 4 of 20 values < 10 ppm (McCormick & Associates 1978). Very high levels of metals were found in tidal wetland sediments at Mill Creek. In some samples, chromium or lead exceeded 15,000 parts-per-million (ppm) and mercury reached 13 ppm (Hartz Mountain Industries 1978). Levels of metals in Meadowlands waters are also high (HMDC 2002).
Until the late 1960s, most of the sewage discharged into the Hackensack River and other Newark Bay tributaries remained untreated (ISC 1967). Many industries discharged their wastes directly into the rivers (Crawford et al. 1994). As recently as the late 1970s, dissolved oxygen levels, a principal indicator of sewage-related contamination, as low as 0.1 mg per liter in the Hackensack River (Mytelka et al. 1981). Coliform and fecal coliform bacteria counts were high (Foote 1983). Water quality is poorest in summer due to reduced freshwater inputs, high water temperatures, and low dissolved oxygen levels (Kraus and Bragin 1988). A recent year-round sampling program recorded annual temperatures in the Hackensack River of 3 to 37 C (37 to 99 F) and an annual range of dissolved oxygen concentrations from 1.0 to 15.5 mg per liter (Day et al. 1999).
A nitrogen budget was estimated for Mill Creek during a single tidal cycle (approximately dawn to dusk) at the season of peak (summer) plant productivity, 4 days after any rain, in 1974 (HMDC 1974). At the study site, a point on Mill Creek ca. 650 meters (2,200 feet) map distance downstream of the Secaucus sewage treatment plant outfall and 350 meters (1,200 feet) upstream of the Hackensack River, Mill Creek drains 108 hectares (267 acres) of marsh characterized by HMDC (1974) as cordgrass-reed-cattail marsh (these marshes may have largely shifted to reed dominance by the time the Hartz Mountain and Mill Creek mitigation projects were initiated about 17 and 3 years ago, respectively). The concentration of total nitrogen in Mill Creek reached a maximum of 10.8 mg per liter at the sampling station during the study. During the tidal cycle, 46 kg of nitrogen were discharged into Mill Creek by the sewage treatment plant. It was calculated that 4,348 kg of nitrogen entered Mill Creek from downstream (i.e. from the Hackensack River), and 4,130 kg of nitrogen left Mill Creek during the tidal cycle. The 5.45% difference (238 kg of nitrogen) was presumed to have been removed from the creek water by the marsh. Dissolved oxygen in the creek water was higher on the outgoing tide than on the incoming tide (HMDC 1974). Thus, despite the input of 46 kg of nitrogen from treated sewage, the water leaving Mill Creek was of better quality (lower nitrogen, higher dissolved oxygen) than the water entering Mill Creek. Marsh “treatment” of polluted waters in the Meadowlands may explain why water quality (e.g. nitrate, dissolved oxygen, total suspended solids; see below) is not worse.
Since 1993, NJMC has monitored approximately 25 water quality parameters quarterly at 14 stations on the Hackensack River estuary, tidal tributaries, and impoundments (HMDC 2002). We examined the data from 6 of these stations selected to represent sites discussed in this report or stations expected to show better and worse conditions: Hackensack River just below Route 46 (near the confluence with Overpeck Creek), Sawmill Creek, Berry’s Creek, upper Cromakill Creek, Kearny Marsh [West], and Belleville Pike Drainage Lagoon. All stations are slightly to moderately brackish, with mean salinities ranging from 10.8 ppt at Sawmill Creek to 1.0 ppt at upper Cromakill Creek. Fecal coliform means, respectively, for the 6 stations are 2,700, 1,019, 1,087, 6,615, 863, and 5,314 counts per 100 ml, with maxima of 5,000-16,000. pH ranges from 5.3 to 8.4 standard units (means for the 6 stations 7.2-7.4). Mean nitrate ranges from 0.2 to 0.5 mg per liter, and mean ammonium ranges from 1.7 to 17.8 mg per liter. Phosphorus has not been monitored. Total suspended solids means range from 24 to 63 mg per liter, with maxima of 96-836 mg per liter (the highest maximum was measured in the Belleville Pike Drainage Lagoon). Total dissolved solids means range from 1,103 to 10,273 mg per liter. Dissolved oxygen means are 5.1-7.8 mg per liter, and minima are 1.0-3.2 mg per liter. Data on oxygen saturation are not available. Clearly, the Hackensack River estuary system is characterized by degraded, urban-industrial water quality (see Kraus 1989).
Prevailing winds in the Meadowlands are from the west; however, winds from all directions, including east, occur (Willis et al. 1973). In 1970, the following average annual concentrations of air pollutants were reported for the Meadowlands (New Jersey Department of Environmental Protection data summarized in Willis et al. 1973): particulates, 113.3 micrograms per cubic meter; sulfur dioxide, 0.043 parts-per-million (ppm); carbon monoxide, 4.24 ppm; hydrocarbons, 2.09 ppm; and nitrogen oxides, 0.113 ppm. Continuous weather and air quality monitoring data are posted on the MERI web site at http://cimic.rutgers.edu/meri/ems_data/index.html.

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