The Hackensack River Watershed, New Jersey/New York: Wetland characterization, preliminary assessment of wetland functions, and remotely-sensed assessment of natural habitat integrity

              The Hackensack River Watershed, New Jersey/New York:
Wetland Characterization, Preliminary Assessment of
Wetland Functions, and Remotely-sensed Assessment of
Natural Habitat Integrity
Produced by the U.S. Fish and Wildlife Service
National Wetlands Inventory Program
Ecological Services, Northeast Region
Hadley, MA
September 2007
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The Hackensack River Watershed, New Jersey/New York:
Wetland Characterization, Preliminary Assessment of
Wetland Functions, and Remotely-sensed Assessment of Natural Habitat Integrity
By Ralph W. Tiner and Herbert C. Bergquist
National Wetlands Inventory Program
Ecological Services
U.S. Fish and Wildlife Service
Northeast Region
300 Westgate Center Drive
Hadley, MA 01035
September 2007
This report should be cited as:
Tiner, R.W. and H.C. Bergquist. 2007. The Hackensack River Watershed, New Jersey/New
York Wetland Characterization, Preliminary Assessment of Wetland Functions, and Remotely-sensed
Assessment of Natural Habitat Integrity. U.S. Fish and Wildlife Service, National
Wetlands Inventory, Ecological Services, Region 5, Hadley, MA. 134 pp. (including
appendices) (Note: Maps in pdf-format are provided in a separate folder and linked to this
report.)
Note: The findings and conclusions in this report are those of the author(s) and do not necessarily
represent the official views of the Service.
Table of Contents
Page
Introduction 1
Study Area 2
Methods 5
Classification and Characterization 5
GIS Analysis and Data Compilation 7
Preliminary Functional Assessment 8
General Scope and Limitations of Preliminary Wetland Functional Assessment 8
Rationale for Preliminary Wetland Functional Assessment 9
Natural Habitat Integrity Assessment 15
Appropriate Use of this Report 22
Results 23
Maps 23
Watershed Findings 23
Wetland Characterization 23
Preliminary Assessment of Wetland Functions 27
Remotely-sensed Indices of “Natural Habitat Integrity” 30
Subbasin Findings 32
Wetland Characterization 32
Preliminary Assessment of Wetland Functions 35
Remotely-sensed Indices of “Natural Habitat Integrity” 35
Conclusions 39
Acknowledgments 41
References 42
Appendices 45
A. Coding for LLWW descriptors from “Dichotomous Keys and Mapping Codes
for Wetland Landscape Position, Landform, Water Flow Path, and Waterbody Type
Descriptors.” 46
B. Study findings for individual subbasins. 57
Berry’s Creek above Paterson Avenue 58
Berry’s Creek below Paterson Avenue 62
Coles Brook-Van Saun Mill Brook 66
De Forest Lake 70
Dwars Kill 75
Hackensack River – Amtrak bridge to Route 3 79
Hackensack River above Tappan Bridge 83
Hackensack River – Bellman’s Creek to Ft. Lee Road 87
Hackensack River below Amtrak bridge 91
Hackensack River – Fort Lee Road to Oradell gage 95
Hackensack River-Nauranshaun Confluence 99
Hackensack River- Oradell to Tappan Bridge 103
Hackensack River – Route 3 to Bellman’s Creek 107
Hirshfeld Brook 111
Overpeck Creek 115
Pascack Brook above Westwood gage 119
Pascack Brook below Westwood gage 123
Tenakill Brook 127
Upper Pascack Brook 131
Maps (linked to report – see Results)
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1
Introduction
Since the late 1970s, the U.S. Fish and Wildlife Service has been conducting fairly detailed
wetland inventories through its National Wetlands Inventory Program (NWI). The maps and
data produced from the NWI have been used to aid and strengthen efforts in wetland protection,
conservation, and management. During the past 15 years, there has been significant progress
made in the development of geographic information system (GIS) technology, availability of
digital geospatial data, and knowledge of the relationships between wetland functions and
characteristics. The Service’s NWI Program now has the capability to use its extensive wetland
geospatial database to produce wetland characterizations, functional assessments, and
assessments of other natural resources for individual watersheds to support restoration planning
and other activities.
The typical wetlands inventory characterizes wetlands mainly by their vegetation and expected
hydrology (water regime), with other modifiers used to indicate human activities (e.g.,
diked/impounded, excavated, farmed, and partly drained) and beaver influence. In order to use
the inventory data to predict functions (e.g., surface water detention, nutrient transformation,
streamflow maintenance, and provision of fish and wildlife habitat), additional information on
the hydrogeomorphic characteristics of wetlands is required. One needs to know where the
wetland is located and its association with a waterbody. The Service has developed a set of
attributes to better describe wetlands by landscape position, landform, water flow path, and
waterbody type (LLWW descriptors; Tiner 2003a). When added to the NWI data, the enhanced
NWI data have a predictive capability regarding wetland functions (Tiner 2003b, 2005a). In
addition to the development of a preliminary wetland functional assessment tool, a set of
remotely-sensed "natural habitat integrity indices" have been developed to characterize the
general status of natural resources in watersheds through remote sensing techniques (Tiner
2004).
The Service’s New Jersey Field Office (NJFO) is actively engaged with other federal and state
agencies and others in natural resource conservation in the Hackensack River watershed
including the Hackensack Meadowlands. NWI mapping in this area was recently updated and
enhanced as part of a Service-wide strategic mapping initiative focused on updating wetland data
for areas where mapping was older than 20 years and/or where significant wetland resources
remain vulnerable to development. Given that New Jersey was the first state completed by the
NWI with late 1970s aerial photography, the NWI maps and data were over 25 years old and in
dire need of updating. Much has changed in this heavily populated state since then and the
original mapping is of limited value for today’s natural resource managers. Although the area
had been remapped, no analysis of the data had been performed.
This report documents the findings of our watershed-wide assessment for the Hackensack River
watershed including the results of the updated and enhanced NWI, a preliminary assessment of
wetland functions, and an assessment of the overall extent of “natural habitat” in the watershed
(“natural habitat integrity”).
2
Study Area
The Hackensack River watershed covers a 197-square mile area in northeastern New Jersey and
southern New York (Figure 1). Most (58%) of the watershed occurs in Bergen County, New
Jersey, with 32 percent in Rockland County, New York and the remaining 10 percent in Hudson
County, New Jersey. The uppermost portion of the watershed is less developed than the highly
urbanized lower portion. The tidal reach of this watershed is mostly comprised by the
Hackensack Meadowlands.
The watershed contains 19 subbasins (Figure 2): 1) De Forest Lake, 2) Upper Pascack Brook, 3)
Hackensack-Nauranshaun Confluence, 4) Pascack Brook above Westwood gage, 5) Hackensack
River above Tappan Bridge, 6) Hackensack River- Oradell to Tappan Bridge, 7) Pascack Brook
below Westwood gage, 8) Dwars Kill, 9) Tenakill Brook, 10) Hirshfeld Brook, 11) Hackensack
River – Fort Lee Road to Oradell gage, 12) Coles Brook-Van Saun Mill Brook, 13) Hackensack
River – Bellman’s Creek to Ft. Lee Road, 14) Overpeck Creek, 15) Hackensack River – Route 3
to Bellman’s Creek, 16) Berry’s Creek above Paterson Avenue, 17) Berry’s Creek below
Paterson Avenue, 18) Hackensack River – Amtrak bridge to Route 3, and 19) Hackensack River
below Amtrack bridge. The latter nine subbasins are subject to tidal influence. Tidal action in
the Coles Brook/Van Saun Mill Brook subbasin is limited to freshwater tidal fluctuations.
3
Figure 1. Major waterbodies and municipalities within the Hackensack River watershed.
(Illustration copyright (c) 1996 by Karen L. Siletti)
4
Figure 2. Subbasins of the Hackensack watershed: 1) De Forest Lake, 2) Upper Pascack Brook,
3) Hackensack-Nauranshaun Confluence, 4) Pascack Brook above Westwood gage, 5)
Hackensack River above Tappan Bridge, 6) Hackensack River- Oradell to Tappan Bridge, 7)
Pascack Brook below Westwood gage, 8) Dwars Kill, 9) Tenakill Brook, 10) Hirshfeld Brook,
11) Hackensack River – Fort Lee Road to Oradell gage, 12) Coles Brook-Van Saun Mill Brook,
13) Hackensack River – Bellman’s Creek to Ft. Lee Road, 14) Overpeck Creek, 15) Hackensack
River – Route 3 to Bellman’s Creek, 16) Berry’s Creek above Paterson Avenue, 17) Berry’s
Creek below Paterson Avenue, 18) Hackensack River – Amtrak bridge to Route 3, and 19)
Hackensack River below Amtrack bridge.
5
Methods
Classification and Characterization
One of the objectives of this project was to expand data in an up-to-date inventory of wetlands
to include attributes for landscape position, landform, water flow path, and waterbody type
(LLWW descriptors). For the updated NWI inventory, 1:40,000 color infrared photography
acquired from 1994-1996 was interpreted following standard NWI procedures (1995 for New
Jersey; 1994-1996 for New York).
After identifying and classifying wetlands according to the Service���s official wetland
classification system (Cowardin et al. 1979), three main descriptors (landscape position,
landform, and water flow path) were applied to each wetland by interpreting available map
information, and in some cases, consulting aerial photographs. "Dichotomous Keys and
Mapping Codes for Wetland Landscape Position, Landform, Water Flow Path, and Waterbody
Type Descriptors" (Tiner 2003a; http://library.fws.gov/wetlands/dichotomouskeys0903.pdf) was
used to classify these features. Other modifiers were added to depict features such as headwater,
drainage-divide, and human-impacted wetlands; waterbodies (e.g., ponds and lakes) were also
classified in more detail.
Landscape position defines the relationship between a wetland and an adjacent waterbody if
present. For the Hackensack River watershed, four landscape positions were possible (map
codes are given in parentheses): 1) estuarine (ES; along salt and brackish tidal waters), 2) lotic
(along rivers [LR] and streams [LS] and on their active floodplains), 3) lentic (LE; along lakes
and reservoirs), and 4) terrene (TE; typically surrounded by upland, but including wetlands
serving as sources of streams). Lotic wetlands were divided into lotic river and lotic stream
wetlands by their width on a 1:24,000-scale map. Watercourses mapped as linear (single-line)
features on NWI maps and on U.S. Geological Survey topographic maps (1:24,000) were
designated as streams, whereas two-lined channels (polygonal features on the maps) were
classified as rivers. All lotic wetlands are in contact with streams or rivers and periodically
inundated by overflow. Wetlands on floodplains surrounded by upland (nonhydric soil) were
classified as terrene wetlands as were nontidal wetlands completely surrounded by dryland and
wetlands that were the source of streams. Lentic wetlands were divided into two categories:
natural and dammed, with the latter type separating wetlands associated with reservoirs from
those along other controlled lakes, when possible.
Landform is the physical form or shape of a wetland. Six landform types were recognized in the
study area: 1) basin (BA), 2) flat (FL), 3) slope (SL), 4) floodplain (FP), 5) island (IL), and 6)
fringe (FR) (Table 1). The floodplain landform was restricted to wetlands bordering perennial
rivers, while fringe wetlands are mostly associated with estuarine waters and semipermanently
flooded vegetated wetlands elsewhere. Where an estuarine wetland is located behind a causeway
(road or railroad) or otherwise partially cut off from the mainbody of a fringing wetland, the
wetland was classified as a basin wetland. Other basin wetlands were depressional wetlands and
seasonally flooded wetlands along streams. Flat wetlands occur on nearly level landforms and
typically have a seasonally saturated or temporarily flooded water regime.
6
Table 1. Definitions and examples of landform types (Tiner 2003a).
Landform Type General Definition Examples
(code)
Basin (BA)* a depressional (concave) landform lakefill bogs; wetlands in the
including artificially created ones by saddle between two hills;
impoundments, causeways, and roads wetlands in closed or open
depressions, including
narrow stream valleys; tidally
restricted estuarine wetlands
Slope (SL) a landform extending uphill (on a slope; seepage wetlands on
typically crossing two or more contours hillside; wetlands along
on a 1:24,000 map) drainageways or mountain
streams on slopes
Flat (FL)* a relatively level landform, often on wetlands on flat areas
broad level landscapes with high seasonal ground-water
levels; wetlands on
terraces along rivers/streams;
wetlands on hillside benches;
wetlands at toes of slopes
Floodplain (FP) a broad, generally flat landform wetlands on alluvium;
occurring on a landscape shaped by bottomland swamps
fluvial or riverine processes
Fringe (FR) a landform occurring within the banks of buttonbush swamps; aquatic
a nontidal waterbody (not on a floodplain) beds; semipermanently
and often but not always subject to near flooded marshes; river and
permanent inundation and a landform stream gravel/sand bars;
along an estuary subject to unrestricted salt and brackish marshes and
tidal flow or a regularly flooded landform flats; regularly flooded tidal
along a tidal freshwater river or stream fresh marsh or flat
Island (IL) a landform completely surrounded by deltaic and insular wetlands;
water (including deltas) floating bog islands
*May be applied as sub-landforms within the Floodplain landform (FPba and FPfl).
7
Water flow path descriptors characterize the flow of water associated with wetlands. Six
patterns of flow were recognized for wetlands and ponds in the Hackensack watershed: 1)
bidirectional-tidal flow (BT), 2) throughflow (TH), 3) outflow (OU), 4) bidirectional-nontidal
flow (BI), 5) inflow (IN), and 6) isolated (IS). Bidirectional-tidal flow reflects tidal influence.
Throughflow wetlands have either a watercourse (e.g., stream) or another type of wetland above
and below it, so water passes through them (usually by way of a river or stream, but sometimes
by ditches). The water flow path of lotic wetlands associated with perennial streams is
throughflow. Lentic wetlands crossed by streams were also designated as throughflow, while
those located in embayments or coves with no stream inflow were classified as bidirectional-nontidal
flow since fluctuating lake or reservoir water levels appear to be the primary surface
water source affecting their hydrology. Outflow wetlands have water leaving them all year-long,
moving downstream via a watercourse (e.g., stream) or a slope wetland. (Note: Some outflow
wetlands have intermittent flow and may be classified as Outflow Intermittent, but this was not
done for this project.) Inflow wetlands or ponds are sinks where no outlet exists, yet water enters
via an intermittent stream or seepage from an upslope wetland. Isolated wetlands are essentially
closed depressions (geographically isolated) where water comes from surface water runoff
and/or groundwater discharge. For this project, surface water connections are emphasized (e.g.,
mapped streams), since it is not possible to determine ground water linkages (especially outflow)
without hydrologic investigations. Consequently, wetlands designated as isolated may have
groundwater connections.
Other modifiers were applied to wetlands in the NWI database. The headwater descriptor (hw)
was applied to lotic wetlands along intermittent streams and first- and second-order perennial
streams and to terrene wetlands that are the sources of these streams. The pond modifer (pd) was
applied to any wetland in contact with a pond. The pond may exert influence on the wetland
vegetation or may simply have little or no influence on the wetland (e.g., where a pond
represents only a small portion of the wetland such as bog eyelet pond or where an artificial pond
was excavated within a vegetated wetland). Wetlands bordering ponds that were mapped by
NWI as impounded should be significantly influenced by pond hydrology.
GIS Analysis and Data Compilation
The geographic information system (GIS) used for this project was Arc GIS 9.0. Several GIS
analyses were performed to produce wetland statistics (acreage summaries), a preliminary
assessment of wetland functions, the remotely-sensed indices of “natural habitat integrity,” and
thematic maps. Tables summarizing the results of the inventory were prepared to show the
extent of different wetland types by NWI classifications and by LLWW descriptors and to
portray differences among the subbasins in these features, wetland functions and natural habitat
integrity. NWI and LLWW wetland acreage totals differ because palustrine open water wetlands
(NWI) were treated as ponds and, in some cases, as lakes according to LLWW.
8
Preliminary Functional Assessment
Ten functions were evaluated using the expanded NWI database: 1) surface water detention, 2)
streamflow maintenance, 3) nutrient transformation, 4) sediment and other particulate retention,
5) coastal storm surge detention, 6) shoreline stabilization, 7) provision of fish and shellfish
habitat, 8) provision of waterfowl and waterbird habitat, 9) provision of other wildlife habitat,
and 10) conservation of biodiversity.
General Scope and Limitations of the Preliminary Wetland Functional Assessment
At the outset, it is important to emphasize that the functional assessment presented in this report
is a preliminary evaluation based on wetland characteristics interpreted through remote sensing
and using available data and the best professional judgment of the senior author with input from
NJFO personnel and others. Wetlands believed to be providing potentially significant levels of
performance for a particular function were highlighted. As the focus of this report is on
wetlands, the assessment of waterbodies (e.g., lakes, rivers, and streams) at providing the listed
functions was not done, despite their rather obvious significant performance of functions such as
fish habitat, waterfowl and waterbird habitat, and surface water detention. No attempt was made
to produce a more qualitative ranking for each function or for each wetland based on multiple
functions since this was beyond the scope of the current study. For a technical review of wetland
functions, see Mitsch and Gosselink (2000); for a broad overview of wetlands, see Tiner
(2005b).
Functional assessment of wetlands can involve many parameters. Typically such assessments
have been done in the field on a case-by-case basis, considering observed features relative to
those required to perform certain functions or by actual measurement of performance and
compared to reference standards. The present study does not seek to replace the need for such
assessments as they are the ultimate assessment of the functions for individual wetlands. For
initial planning purposes, a more generalized assessment is worthwhile for targeting wetlands
that may provide certain functions, especially for those functions dependent on landscape
position and vegetation lifeform. Subsequently, these results can be field-verified when it comes
to actually evaluating particular wetlands for acquisition or other purposes. Current aerial
photography may also be examined to aid in further evaluations (e.g., condition of
wetland/stream buffers or adjacent land use) that can supplement the preliminary assessment.
This study employs a watershed assessment approach called "Watershed-based Preliminary
Assessment of Wetland Functions" (W-PAWF). W-PAWF applies general knowledge about
wetlands and their functions to develop a watershed overview that highlights possible wetlands
of significance based on their predicted level of performance of various functions. To
accomplish this objective, the relationships between wetlands and various functions must be
simplified into a set of practical criteria or observable characteristics. Such assessments could
also be further expanded to consider the condition of the associated waterbody and the
neighboring upland or to evaluate the opportunity a wetland has to perform a particular function.
W-PAWF does not account for the opportunity that a wetland has to provide a function resulting
from a certain land-use practice upstream or the presence of certain structures or land-uses
9
downstream. For example, two wetlands of equal size and like vegetation may be in the right
landscape position to retain sediments. One, however, may be downstream of a land-clearing
operation that has generated considerable suspended sediments in the water column, while the
other is downstream from an undisturbed forest. The first wetland is likely to trap more water-borne
sediments than the latter at the present time, however should the forest above the latter
wetland be cleared, the latter wetland will likewise trap any water-borne sediments. The W-PAWF
is therefore designed to reflect the potential for a wetland to provide a function. W-PAWF
also does not consider the condition of the adjacent upland (e.g., level of outside
disturbance) or the actual water quality of the associated waterbody, both of which affect
wetland functions and habitat quality. Collection and analysis of these data were beyond the
scope of the study.
This preliminary assessment does not obviate the need for more detailed assessments of the
various functions. It should be viewed as a starting point for more rigorous assessments, as it
attempts to cull out wetlands that may likely produce significant levels of performance for
certain functions based on generally accepted principles and the source information used for this
analysis. This type of assessment is most useful for regional or watershed planning purposes.
It is also important to recognize limitations derived from source data including conservative
interpretations of forested wetlands (especially evergreen types) and drier-end wetlands (e.g., wet
meadows, especially those used as pastures; see Tiner 1997b for additional information), and the
omission of small or narrow wetlands and small streams. Some wetlands classified as isolated
types may actually be connected by a small stream that was not shown on a topographic map or
digital hydrography layer. Wetlands directly across the road from other wetlands were assumed
to be connected by a culvert or similar structure. Despite limitations of source data, the NWI
dataset created for this project represents the most current database on the distribution, extent,
and type of wetlands in the watershed. NWI data for this study were based on 1994-1996 aerial
photography (1995 for New Jersey and variable photo dates for the New York portion).
Rationale for the Preliminary Wetland Functional Assessment
The criteria used for identifying wetlands of significance for these functions were taken from
“Correlating Enhanced National Wetlands Inventory Data With Wetland Functions for
Watershed Assessments: A Rationale for Northeastern U.S. Wetlands” (Tiner 2003b;
http://www.fws.gov/nwi/pubs_reports/HGMReportOctober2003.pdf), but were modified for the
Hackensack Meadowlands due to the predominance of common reed (Phragmites australis). The
abundance of this species may reduce certain functions, especially for fish and shellfish and
waterfowl and waterbird habitat (see below). A list of the wetland types designated as
significant for each function is presented in Table 2.
Treatment of Common Reed Marshes
Common reed is the number one invasive plant threatening estuarine wetlands in the
northeastern United States. It has replaced typical salt marsh plants such as smooth cordgrass
(Spartina alterniflora), salt hay grass (Spartina patens), salt grass (Distichlis spicata), and black
rush (Juncus gerardii) in areas where tidal flow has been significantly restricted and where fill
10
has been deposited in wetlands. Common reed is a good disturbance indicator as it readily
colonizes exposed soils in the coastal areas and even inland areas along highways (see Marks et
al. 1994; Chambers et al. 1999). Although common reed is native to North America, the spread
of this species since the 1950s has been attributed to a non-native variety (Saltonstall 2002).
Natural stands were typically limited to the edges of estuarine wetlands (Orson et al. 1987).
With the advance of common reed into the marsh interior and even along creekbanks, the basic
structure of salt marshes has changed from a low-lying grassland to a veritable thicket of tall
reeds often with a thick mat of decomposed plant material on the surface. Plant diversity usually
declines with the invasion of Phragmites as this species commonly forms monotypic stands,
especially in brackish waters (Meyerson et al. 2000). Given the extent of common reed in
today's estuarine environments, there has been considerable recent attention given to the habitat
function of this species in comparision to that of the pre-existing salt marsh (e.g., Meyerson et al.
2000). Changes in plant composition typically alter the habitat use by many species. A brief
summary of the state-of-our-knowledge on the uses of common reed as habitat follow. For more
detailed information, refer to the specific articles referenced.
Common reed is a productive plant and its biomass exceeds that of most marsh species it
replaces. Recognizing that one of the major ecological functions of salt marshes is to produce
material for the detrital food web of estuaries, the export and decomposition of plant materials is
important. Common reed leaves decompose rapidly, but the stems take longer to decompose
than the plants it replaces (Meyerson et al. 2000). Stem and stem litter remain on the marsh for
years. This has given Phragmites an edge in carbon and other nutrient sequestration over other
species. The presence of this species at sewage outfalls is testimony to its competitive advantage
over other plants in occupying eutrophied sites (Freeman undated manuscript; Levine et al. 1998)
and its high potential for nutrient transformation.
There is general agreement that pure Phragmites stands generally yield poorer quality wildlife
habitat than the marshes they replace, while they may be important for some species (Roman et
al. 1984; Kiviat 1987). The tall, dense reeds restrict wildlife movement and also adversely affect
hydrology with negative impacts on aquatic species. Over 50 species of birds have been found
in common reed marshes (Meyerson et al. 2000). Despite this usage, there are no birds that
depend solely on these wetlands. Common birds in the east include marsh wren, red-winged
blackbird, and swamp sparrow. Ringed-necked pheasant and American bittern have been
observed (R. Tiner, personal observations). The average number of bird species may be lower in
Phragmites wetlands than in salt marshes (Benoit and Askins 1999). Phragmites in mixed
stands, common reed marshes along large pools, and the edges of reed marshes seem to be better
bird habitats than the marsh interior (Buchsbaum 1997; Cross and Fleming 1999, Meyerson et al.
2000). Given this, regularly flooded mixed and pure stands dominated by Phragmites and
irregularly flooded reed marshes that are contiguous with estuarine waters will be rated as
moderate for the provision of waterfowl and waterbird habitat. Pure stands of irregularly flooded
Phragmites separated from water ("interior marsh") will not be rated as significant for waterfowl
and waterbirds, although their value to other birds is recognized under the "other wildlife habitat"
function. (Note: Many reed marshes are adjacent to water and will therefore be rated as
moderate; recognize, however, that the interior portions of these marshes are used less by
waterfowl and waterbirds than the shoreline sections.)
11
Marsh flooding provides access for fish and nektonic invertebrate use and anything reducing this
process will have a negative impact on its use by these organisms. Common reed is known to
accelerate the buildup of the marsh surface and reduce drainage density by filling in small
ditches and creeks (Weinsten and Balleto 1999), thereby restricting access to the marshes by
fishes and transient shellfish. Reducing the frequency of tidal flooding has obvious negative
consequences for aquatic species. Fish and shellfish density in Phragmites stands vary with
hydrology and wetland geomorphology (Hanson et al. 2002). They noted that high stem density
and litter accumulation may reduce tidal flow rates, leading to a reduction in the depth of tidal
flooding. From the surface of a brackish Phragmites marsh along the Hudson River, they
collected common mummichog (Fundulus heteroclitus), herrings (Alosa spp.), grass shrimp
(Palaemonetes pugio), and blue crab (Callinectes sapidus). Most of the individuals were
captured in the marsh near the creekbanks and only a few in the marsh interior. Depositional
sites produced the most individuals and greatest biomass, but other studies have not yielded
similar findings (Rozas 1992). Some studies have found a greater abundance of mummichog in
Spartina marshes than in neighboring Phragmites marshes (Able and Hagan 2003, Hanson et al.
2002). Regularly flooded reed marshes will be ranked as having moderate potential for fish and
shellfish; irregularly flooded Phragmites marshes contiguous with estuarine open water will be
similarly rated as will nontidal, semipermanently flooded reed marshes contiguous to an open
waterbody. Interior reed marshes (not bordering a waterbody) will not be viewed as potentially
significant fish and shellfish habitat.
12
Table 2. List of wetlands of potential significance for ten functions for use in the Hackensack River Watershed. (Source: Adapted
from Tiner 2003b). See Appendix A for LLWW coding. NWI codes: L2 = lacustrine littoral, P = palustrine, E2 = estuarine intertidal,
AB = aquatic bed, EM = emergent, EM1 = persistent emergent, EM5 = Phragmites, SS = scrub-shrub, FO = forested, US =
unconsolidated shore, RS = rocky shore, SB = streambed, H = permanently flooded, F = semipermanently flooded, E = seasonally
flooded/saturated, C = seasonally flooded, A = temporarily flooded, B = saturated, L = subtidal, N = regularly flooded (tidal), P =
irregularly flooded (tidal), R = seasonally flooded-tidal, T = semipermanently flooded-tidal, S = temporarily flooded-tidal.
Function Level of Function Wetland Types
Surface Water Detention High ESFR, ESBA, ESIL, LEBA, LEFR, LEFL (in reservoir and dammed areas only),
LEIL, LSBA, LRBA, LSFP, LRFP, LSFR, LRFR, LRIL, MAFR, MAIL, PDTH,
TEFRpdTH, TEBApdTH, PDBI, PDBT, TEBApdBT, TEBATH. TEBATI
Moderate LRFL, LSFL, LEFL, TEIF, TEBA (other than above), PD (other except PD2f),
TE__pd (other), TEFP__
Coastal Storm Surge
Detention High ESBA, ESFR, ESIL, LR5FR, LR5FP (=LR5BA and LR5FL), LR5IL, MAFR
Streamflow Maintenance High hw (not dr = not ditched)
Moderate hwdr, LR1FP, PDTH, TE__pdTH, PDOU, TE__pdOU, TEOU (not hw but
associated with streams not rivers), LE wetlands associated with throughflow lakes
(LK__TH)
Nutrient Transformation High P__(AB, EM, SS, FO and mixes )C, P__(AB, EM, SS, FO and mixes)E, P__(AB,
EM, SS, FO and mixes)F, P__(AB, EM, SS, FO and mixes)R, P__(AB, EM, SS,
FO and mixes)T, P__(AB, EM, SS, FO and mixes)N, P__(AB, EM, SS, FO and
mixes)H, P__(AB, EM, SS, FO and mixes)L, E2EM, E2SS, E2FO, P__(AB, EM,
SS, FO and mixes)B (not on coastal plain or glaciolacustrine plain)
Moderate P__(AB, EM, SS, FO and mixes)B (on coastal plain or glaciolacustrine plain),
P__(AB, EM, SS, FO)A, P__(AB, EM, SS, FO and mixes)S
Sediment and Other
Particulate Retention High ES__(vegetated), LEBA, LEFR(vegetated), LEIL(veg), LSBA, LRBA, LSFP,
LRFP, LRFR(veg), LSFR(veg), LRIL (veg), PDTH, TE__pdTH (including __pq),
PDBI, TE__pdBI (including __pq), PDBT, TE__pdBT, TEBATH, TEBATI,
13
TEIFbaTH, TEIFbaTI
Moderate E2__(US, SB, excluding RS), LSFL(not PSS_Ba or PFO_Ba), LRIL (nonveg),
LRFR(nonveg), LSFR (nonveg), M2US, TEBA(not PSS_Ba or PFO_Ba), PD
(not c, d, e, f, g, j types), TE__pd(not PSS_Ba or FO_Ba), TEFP__
Shoreline Stabilization High E2__(AB, EM, SS, FO and mixes), E2RS (not ESIL), M2RS(not MAIL),
LR_(AB, EM, SS, FO and mixes; not LRIL), LS_(AB, EM, SS, FO and mixes),
LE__(AB, EM, SS, FO and mixes; not LEIL)
Moderate TE__pd (AB, EM, SS, FO and mixes), TE__OUhw (AB, EM, SS,
FO and mixes)
Fish and Shellfish Habitat High E2EM (including mixes with other types where EM1 or EM2 predominates;
excluding E2EM5P__ and mixes where EM5 predominates and mixed
communities dominated by E2FO or E2SS), E2US, E2RF, E2AB, E2RS (vegetated
with macroalga; may be classified as E2AB1), L2_F, L2AB, L2UB/__(AB, EM,
SS, FO), LE__ (vegetated; AB, EM, SS, FO) and NWI water regime = H
(permanently flooded), M2AB, M2RS, M2US, M2RF (vegetated with macroalga;
may be classified as M2AB1), P__F and adjacent to PD, LK, RV (all except RV4),
ST (all except ST4), or EY waters, PAB, PUB/__(AB, EM, SS, FO), P__(EM, SS,
FO)H, PEM__(N,R,T, or L, except EM5), PD associated with P__(AB, EM, SS,
FO)F, R1EM, R1US(except S)
Moderate LE__ and PEM1E, LR__ and PEM1E (and mixes), LS__ and PEM1E (and mixes),
PEM5F and adjacent to LK, RV (except RV4), ST(except ST4) and EY, E2EM5N
(and mixes), PEM5N (and mixes), E2EM5P__ and adjacent to the estuary (and
mixes, but not "interior" E2EM5P_), E2FO/EM__ (not EM5), E2SS/EM__ (not
EM5), LR5__ and PFO/EM_R or T (not EM5), LS5__ and PFO/EM_R or T (not
EM5), PD (except c, d, e, f, g, j types), EY; PD (except c, d, e, f, g, j types);
TEFRpd (along these ponds)
Stream Shading LS (not LS4) and PFO, LS (not LS4) and PSS (not PSS_Ba)
Waterfowl and Waterbird
Habitat High E2EM1 or E2EM2 (includes mixes where they predominate ), E2US__ M, N, P,
and T water regimes (not S water regime), E2RF, E2AB, E2RS, L2_F (vegetated,
AB, EM, SS, FO and mixes with nonvegetated), L2AB (and mixes with
nonvegetated), L2US_(F,E, or C), L2_H (vegetated, AB, EM, SS, FO and mixes
with nonvegetated), M2AB, M2RS, M2US, M2RF, P__F (excluding EM5-
14
dominated wetlands) and adjacent to PD, LK, RV(not RV4) ST(not ST4), or EY
waters; PAB, P__H (vegetated, EM, SS, FO including mixes with UB), P__Eh,
P__Eb; LS__ and PEM1E (including mixes), LR__ and PEM1E (including
mixes), TE__ hw and PEM1E;, PEM__N,R,T, or L (includes mixes, but excludes
Phragmites-dominanted EM5), PD associated with P__(AB, EM, SS, FO)F,
PEM1R (and mixes), PEM1T (and mixes), PUB__b, R1EM, R1US (except S
water regime)
Moderate E2EM5N (and mixes), E2EM5P (and mixes) and contiguous with open water (not
"interior" marshes), PEM5__E,F, R, or T and adjacent to PD, LK, RV(not RV4),
ST(not ST4), or EY, other L2UB (not listed as high), Other PD (except c, d, e, f, g,
j types), PEM1E__ (including mixes) and associated with PD, LK, RV(not RV4),
or ST(not ST4)
Wood Duck LS(1,2, or 5)BA and P__ (FO or SS and mixes), LS(1,2, or 5)FR and P__ (FO or
SS and mixes), LR(1,2, or 5)FPba and P__(FO or SS and mixes), LR(1,2, or 5)BA
and P__(FO or SS and mixes), LRFPba and PFO/EM, LRFPba and PUB/FO;
PFO_R, T, or L (and mixes) and contiguous with open water, PSS_R, T, or L (and
mixes) and contiguous with open water
Other Wildlife Habitat High Any wetland complex > 20 acres, wetlands 10-20 acres with 2 or more classes
(excluding EM5), small isolated wetlands in dense cluster in a forest matrix
(restrict to forest regions of U.S. with woodland vernal pools)
Moderate Other vegetated wetlands
Conservation of
Biodiversity Regional significant
for Northeast U.S E2EM1N, E2EM1P6, R1EM, R1US, PEM1N, PEM1R, PEM2N,
PEM2R, PSS_R, PSS_T, PFO4__g (Atlantic white cedar), PEM__i
(herbaceous fen), PSS__i (shrub fen), PFO__i (treed fen), PFO2__
(bald cypress), E1AB__ (eelgrass and SAV beds), LS__FR, LR__FR,
PD1m (woodland vernal pool; small ponds surrounded by forest), forested wetlands
within >7410-acre forest, very large wetland complexes (> 100 acres)
Locally significant Beaver-influenced wetlands, Estuarine emergent wetlands (except Phragmites),
in the Northeast contiguous wetlands within the Meadowlands District, headwater wetlands, Lentic
fringe and basin wetlands (> 10 acres), Lotic River or Stream wetland complexes
15
Natural Habitat Integrity Assessment
For this assessment, a geospatial database covering the entire Hackensack River watershed was
created. Wetland data were obtained from the updated NWI database. Land use and land cover
data for upland areas in the watershed were created through photointerpretation of the 1994-1996
aerial photography. The Anderson et al. (1976) land use and land cover (LULC) classification
system was used to classify upland areas. The following categories were among those identified:
developed land, agricultural land, forests, wetlands (from NWI data), transitional land (moving
toward some type of development or agricultural use, but future status unknown), and water.
This update focused on changes between “natural” habitat and developed land and, therefore,
does not represent a comprehensive revision of all LULC categories. Stream data came from
USGS 1:24,000 digital hydrography data and many small streams (especially intermittent ones in
hilly and mountainous terrain) are often not designated. These data were not improved since
stream mapping was not part of the project and this method typically uses the best available
recent data on land use/cover, streams, and wetlands for assessment.
We applied the remotely sensed indices of “natural habitat integrity” (Tiner 2004) to the
geospatial dataset for the Hackensack watershed. These indices were designed to meet four of
the following requirements: 1) derived from air photointerpretation and/or satellite image
processing for contemporary data and from maps for historical data, 2) suitable for frequent
updating and rapid assessment, 3) consist of metrics that could efficiently and cost effectively be
updated for large geographic areas, 4) present a broad view of the condition of “natural habitat,”
and 5) provide a historic perspective on the extent of wetlands and open waterbodies. Such
indices represent coarse-filter variables for assessing the overall condition of watersheds. They
were intended to augment, not supplant, other more rigorous, fine-filter approaches for
describing the ecological condition of watersheds (e.g., Index of Biological Integrity for instream
macroinvertebrates and fish, and the extent of invasive species) and for examining human
impacts on natural resources.
Eleven indices were calculated for this assessment. Six indices address habitat extent (i.e., the
amount of natural habitat occurring in the watershed and along wetlands and waterbodies) and
four indices deal with habitat disturbances (emphasizing human alterations to streams, wetlands,
and terrestrial habitats), whereas the remaining index is a composite index integrating results
from the other ten indices and reflecting the overall natural condition of the watershed. The six
“natural” habitat extent indices are “natural” cover, river-stream corridor integrity, vegetated
wetland buffer integrity, pond and lake buffer integrity, wetland extent, and standing waterbody
extent. The four “habitat disturbance indices” involve dammed stream flowage, channelized
stream flowage, wetland disturbance, and habitat fragmentation by roads. The last index -
“composite natural habitat integrity index” - is comprised of the weighted sum of all the other
indices, with the disturbance indices subtracted from the habitat extent indices to yield an overall
“natural habitat integrity” score for a watershed or subbasin. All indices have a maximum value
of 1.0 and a minimum value of zero. For the habitat extent indices, the higher the value, the
more habitat available. For the disturbance indices, the higher the score, the more disturbance.
For purposes of this study, “natural habitats” are defined as areas where significant human
activity is limited to activities such as nature observation, hiking, hunting, fishing, or timber
16
harvest, and where vegetation is allowed to grow for many years without annual harvesting of
vegetation or fruits and berries for commercial purposes. While natural habitats are essentially
plant communities represented by forests, meadows, shrub thickets, and wetlands where resident
and migratory wildlife find food, shelter, and water, they are not restricted to pristine habitats
and may include managed habitats (e.g., commercial forests and wildlife impoundments), and
forests, fields, and thickets adjoining residential properties, plus wetlands now colonized by
invasive species (e.g., Phragmites australis or Lythrum salicaria). “Natural vegetation” is the
plant community growing in these habitats.
Natural habitat integrity is broadly defined as conditions where “natural habitat” is typically
allowed to exist for many years, without great disturbance or alteration by humans. This is quite
different from the concept of biological integrity proposed by Angermeier and Karr (1994)
emphasizing conditions with little or no human influence. The indices do not include certain
qualitative information on the condition of existing habitats as reflected by the presence,
absence, or abundance of invasive species or the degree of forest fragmentation, or contaminant
concentration and availability. The level of effort required to inject more qualititative data into
the analysis may preclude their use in remotely-sensed ecological assessments. Weighting of
natural woodlands versus commercial forests may be a practical option for this type of
assessment, but it was not explored. Another consideration would be establishment of minimum
size thresholds to determine what constitutes a viable “natural habitat” for analysis (e.g., 0.04
hectare/0.1 acre patch of forest or 0.4 hectare/1 acre minimum?). Other indices (e.g., index of
ditching density for agricultural and silvicultural lands) may also be useful for water quality
assessments.
Habitat Extent Indices
These indices provide an assessment of the amount of “natural vegetation” or “natural habitat”
that occurs in a watershed, including strategic locations important for water quality and
aquatic/wetland wildlife. Data for the indices come from analyses of the land use/cover and
wetlands geospatial data for the watershed. The following areas are emphasized: the entire
watershed, stream and river corridors, vegetated wetlands and their buffers, and pond and lake
buffers. The extent of standing waterbodies is also included to provide information on the
quantity of aquatic habitat in the watershed.
The Natural Cover Index (INC) is the proportion of a watershed that is wooded or “natural” open
land (e.g., emergent wetlands, “old fields,” or sand dunes, but not cropland, hayfields, lawns,
turf, or pastures), excluding open water.
INC = ANV/AW , where ANV (area in “natural” vegetation) equals the area of the
watershed=s land surface in Anatural@ vegetation and AW is the total land surface area of
the watershed (excluding open water).
Significance of index: provides information on how much of a watershed is not
developed and may be serving as important wildlife habitat.
The River-Stream Corridor Integrity Index (IRSCI) is derived by considering the condition of the
17
land bordering perennial rivers and streams.
IRSCI = AVC/ATC , where AVC (vegetated river-stream corridor area) is the area of the
river-stream corridor that is colonized by Anatural vegetation@ and ATC (total river-stream
corridor area) is the total area of the river-stream corridor.
Significance of index: provides information on the status of vegetated riparian corridors.
The width of the river-stream corridor may be varied to suit project goals, but a 200-meter
corridor (100m on each bank of the river or stream) was used for this study due to interest in
wildlife habitat. Note that these corridors include banks of impounded sections of rivers and
streams, so that a continuous river or stream corridor is evaluated. The corridor area does not
include the waterbody. For the Hackensack watershed, the index was applied to nontidal rivers
and streams for assessing the composite natural habitat integrity index.
The Wetland Buffer Integrity Index (IWB) measures the condition of wetland buffers within a
specified distance (e.g., 100m) of mapped vegetated wetlands for a watershed.
IWB = AVB/ATB , where AVB (area of vegetated buffer) is the area of the buffer zone that is
in natural vegetation cover and ATB is the total area of the buffer zone.
Significance of index: provides information on vegetated buffers around wetlands that are
important for wildlife and for reducing impacts to wetland water quality from surface
runoff.
This buffer is drawn around existing vegetated wetlands and while the buffer zone may include
open water, the buffer index focuses on land areas that are capable of supporting free-standing
vegetation. For the Hackensack watershed, a 100m buffer was examined.
The Pond and Lake Buffer Integrity Index (IPLB) addresses the status of buffers of a specified
width around these standing waterbodies (excluding instream impoundments that are part of the
river-stream corridor integrity index):
IPLB = AVB/ATB , where AVB (area of vegetated buffer) is the area of the buffer zone that
is in natural vegetation cover and ATB is the total area of the buffer zone.
Significance of index: documents the condition of vegetation in a zone surrounding these
waterbodies which is important for both water quality and aquatic life (buffer from
impacts associated with adjacent urban/suburban development, agriculture, and other
human actions).
Vegetated ponds are mapped as a vegetated wetland type and their buffers are not included in
this analysis, but instead are evaluated as wetland buffers. For the Hackensack River watershed
analysis, a 100m buffer was examined.
18
The Wetland Extent Index (IWE) compares the current extent of vegetated wetlands (excluding
nonvegetated, open-water wetlands) to the estimated historic extent.
IWE = ACW/AHW , where ACW is the current area of vegetated wetland in a watershed and
AHW is the historic vegetated wetland area in the watershed.
Significance of index: gives historical perspective on wetland loss.
The IWE is an approximation of the extent of the original wetland acreage remaining in a
watershed. Farmed wetlands are included where cultivation is during droughts only, since they
are likely to support Anatural vegetation@ during normal and wet years. Where farmed wetlands
are cultivated more or less annually, they are not included in the area of vegetated wetland, since
they lack “natural vegetation” in most years and only minimally function as wetland. Hydric soil
data are used to generate the historic extent of wetlands. To calculate the wetland extent index
for the watershed and subbasins hydric soils data were available for all counties portion of the
watershed except Hudson; a historic map of the Hackensack Meadowlands from 1889 was used
for this area (Tiner et al. 2002).
The Standing Waterbody Extent Index (ISWE) addresses the current extent of standing fresh
waterbodies (e.g., lakes, reservoirs, and open-water wetlands - ponds) in a watershed relative to
the historic area of such features.
ISWE = ACSW/AHSW , where ACSW is the current standing waterbody area and AHSW is the
historic standing waterbody area in the watershed.
Significance of index: gives perspective on changes in waterbody area (historic vs.
today).
From a practical standpoint, this index is estimated. For most areas, including the Hackensack
watershed, a net gain in ponds and impoundments has occurred over time. Every national
wetland trend study (Frayer et al. 1983, Tiner 1984, Dahl and Johnson 1991, Dahl 2000) has
shown an increase in pond area as ponds are constructed for a multitude of purposes. For these
situations, the ISWE value is 1.0+ indicating a gain in this aquatic resource and no specific
calculations necessary; a value of 1.0 is then used for determining the composite natural habitat
integrity index for the study area. In geographic areas where significant loss of open water has
occurred, an estimate will need to be derived from available sources (including historic maps).
Habitat Disturbance Indices
A set of four indices have been developed to address alterations to natural habitats. For these
indices, a value of 1.0 is assigned when all of the streams or existing wetlands have been
modified.
19
The Dammed Stream Flowage Index (IDSF) highlights the direct impact of damming on rivers and
streams in a watershed.
IDSF = LDS/LTS , where LDS is the length of perennial streams impounded by dams
(combined pool length) and LTS is the total length of perennial streams in the watershed
(including the length of instream pools).
Significance of index: reveals how much of the stream system has been dammed.
Note that the total stream length used for this index will be greater than that used in the
channelized stream length index, since the latter emphasizes existing streams and excludes
dammed segments. For this project, this index was applied only to linear streams (not rivers); in
the future, this index should be expanded to include the entire river-stream length (i.e., the
Dammed River-Stream Flowage Index).
The Channelized Stream Length Index (ICSL) is a measure of the extent of stream channelization
within a watershed.
ICSL = LCS/LTS , where LCS is the channelized stream length and LTS is the total stream
length for the watershed.
Significance of index: documents the magnitude of stream channelization.
Since this index addresses channelization of existing streams, it focuses on the linear streams.
The index will usually emphasize perennial streams as it does for the Hackensack study, but
could be expanded to include intermittent streams, if desirable. The total stream length does not
include the length of: 1) artificial ditches excavated in farm fields and forests, 2) dammed
sections of streams, and 3) polygonal portions of rivers. Channelization of the latter may be
represented by a separate index or combined with this index to form a Channelized River/Stream
Length Index.
The Wetland Disturbance Index (IWD) focuses on alterations within existing wetlands. As such,
it is a measure of the extent of existing wetlands that are diked/impounded, ditched, excavated,
or farmed.
IWD = ADW/ATW , where ADW is the area of disturbed or altered wetlands and ATW is the
total wetland area in the watershed.
Significance of index: identifies the degree to which existing wetlands have been altered
by human actions.
Wetlands are represented by both vegetated and nonvegetated (e.g., shallow ponds) types
including natural and created wetlands. Since the focus of analysis is on Anatural habitat,@ diking
or excavating wetlands (or portions thereof) is viewed as an adverse action. It is recognized,
however, that many such wetlands serve as valuable wildlife habitats (e.g., waterfowl
impoundments), despite such alteration.
20
The Habitat Fragmentation by Road Index (IHF) attempts to address habitat fragmentation by
roads.
IHF = AR/AW x 16 , where AR is the area of roads (interstates, state/county and other
roads) and AW is the total land area of the watershed.
Significance of index: indicates habitat fragmentation by roads, but likely reflects
degradation of water quality, and terrestrial and aquatic ecosystems from associated
development.
Since road area will never equal 100 percent of a watershed, a multiplier was created to increase
the index value to a level of relevance for the composite index (remotely-sensed index of natural
habitat integrity). A multiplier of 16 was established based on examination of road density in a
portion of Jersey City, NJ with extremely high road density (0.06 road area/city area);
multiplying by 16 would yield an index value near 1.0 (the estimated maximum road area/unit
area). If this multiplier yields an index value greater than 1.0, use 1.0 for the value when
computing the composite index. (Note: This would only happen if an entire watershed or
subbasin had higher road density than Jersey City, NJ which would be a rare situation.)
While limited to road fragmentation, this index serves a surrogate for habitat fragmentation and
degradation. Two watersheds may have the same amount of natural habitat, but may differ in the
extent of roads. Although not the only human action that causes habitat fragmentation, road
density is closely correlated to degraded ecosystems (Miller et al. 1996, Quigley and Arbelbide
1997, Forman and Alexander 1998, Forman 2000, and Trombulak and Frissell 2000). Moreover,
adverse impacts from other development (e.g., urban and suburban) are likely related to the
extent of roads, especially paved roads. More detailed assessments of habitat fragmentation,
including mean patch size, patch density, edge density, and total core area, could be performed,
if necessary.
For the Hackensack watershed study, we used the same road widths used in prior studies (Tiner
2004) to calculate AR: interstates (2 lanes/direction) - 12.1m, state roads (2 lanes; 1
lane/direction) - 12.1m, county/local roads (2 lanes; 1 lane/direction) - 11.5m, and dirt roads (2-
lanes) - 6.7m. These widths tended to match well with similar roads in the Hackensack
watershed. Road widths were applied to road lengths to calculate area of roads for the study
area.
Composite Habitat Integrity Index for the Watershed
The Composite Natural Habitat Integrity Index (ICNHI) is a combination of the preceding indices.
It seeks to express the overall condition of a watershed in terms of its potential ecological
integrity or the relative intactness of Anatural@ plant communities and waterbodies, without
reference to specific qualitative differences among these communities and waters. Variations of
ICNHI may be derived by considering buffer zones of different widths around wetlands and other
aquatic habitats (e.g., ICNHI 100 or ICNHI 200) and by applying different weights to individual indices
or by separating or aggregating various indices (e.g., stream corridor integrity index, river
21
corridor integrity index, or river-stream corridor integrity index). The weighting of the indices
come from Tiner (2004) and although subjective, the results of this analysis are comparable
among the subbasins examined. The same weighting scheme must be used whenever
comparisons of this index are made between and within watersheds.
For the analysis of Hackensack River watershed, the following formula was used to determine
this composite index:
ICNHI 100 = (0.5 x INC) + (0.125 x IRSCI200) + (0.125 x IWB100) + (0.05 x IPLB100)+ (0.1 x IWE),
+ (0.1 x ISWE) - (0.1 x IDSF) - (0.1 x ICSL) - (0.1 x IWD) - (0.1 x IHF), where the condition of
a 100m buffer is used throughout.
Significance of index: gives an overview of the condition of the watershed relative to the
existence of “natural” habitat and a measure that can be compared with other watersheds.
The indices were applied to the watershed as a whole and to individual subbasins.
22
Appropriate Use of this Report
The report provides a basic wetland characterization, a preliminary assessment of wetland
functions, and a remotely-sensed assessment of “natural habitat” integrity for the Hackensack
River watershed. Keeping in mind the limitations mentioned previously, the results are an initial
screening of the watershed's wetlands to designate wetlands that may have a significant potential
to perform different functions and to assess the general condition or state of “natural habitat”
throughout the basin. The targeted wetlands have been predicted to perform a given function at a
significant level presumably important to the watershed's ability to provide that function.
"Significance" is a relative term and is used in this analysis to identify wetlands that are likely to
perform a given function at a level above that of wetlands not designated.
While the results are useful for gaining an overall perspective of a watershed's wetlands and their
relative importance in performing certain functions, the report does not identify differences
among wetlands of similar type and function. The latter information is often critical for making
decisions about wetland acquisition and designating certain wetlands as more important for
preservation versus others with the same classification.
The report is useful for general natural resource planning, as a screening tool for prioritization of
wetlands (for acquisition or strengthened protection), as an educational tool (e.g., helping the
public and nonwetland specialists better understand the functions of wetlands and the
relationships between wetland characteristics and performance of individual functions), and for
characterizing the differences among wetlands in terms of both form and function within a
watershed.
23
Results
The results are presented for the entire watershed and for each of its 19 subbasins. The
watershed findings consist of a summary of wetland types, a preliminary assessment of functions
for wetlands in the Hackensack watershed, and an assessment of the “natural habitat integrity”
derived from remote sensing techniques. Data for corresponding subbasins are summarized in
this section while the detailed results presented in tabular form in Appendix B.
Maps
Maps are presented in a separate folder and are hyperlinked to the report. A series of 16 maps
was produced for the Hackensack River watershed with subbasin boundaries shown. All maps
were produced at a scale of 1:75,000 for this report. A list of the 16 maps follows: Map 1 -
Wetlands and Deepwater Habitats Classified by NWI Types, Map 2 - Wetlands Classified by
Landscape Position, Map 3 - Wetlands Classified by Landform, Map 4 - Wetlands Classified by
Landscape Position and Landform, Map 5 – Potential Wetlands of Significance for Surface
Water Detention, Map 6 - Potential Wetlands of Significance for Streamflow Maintenance, Map
7 - Potential Wetlands of Significance for Nutrient Transformation, Map 8 - Potential Wetlands
of Significance for Sediment and Other Particulate Retention, Map 9 – Potential Wetlands of
Significance for Coastal Storm Surge Detention, Map 10 - Potential Wetlands of Significance for
Shoreline Stabilization, Map 11 - Potential Wetlands of Significance for Fish and Shellfish
Habitat, Map 12 - Potential Wetlands of Significance for Waterfowl/Waterbird Habitat, Map 13 -
Potential Wetlands of Significance for Other Wildlife Habitat, Map 14 – Potential Wetlands of
Significance for the Conservation of Biodiversity, Map 15 – Extent of “Natural Cover” in the
Hackensack River Watershed, and Map 16 – Condition of River and Stream Corridors.
Watershed Findings
Wetland Characterization
Wetlands by NWI Types
According to the NWI, the Hackensack watershed had nearly 9,650 acres of wetlands (including
ponds) (Table 3; Map 1). Estuarine emergent wetlands were the predominant wetland type
comprising 42 percent of the watershed’s wetlands. Palustrine forested wetlands were next
ranked in abundance, accounting for 33 percent of all wetlands. Tidal flats (estuarine
unconsolidated shore) associated with the Hackensack Meadowlands were third-ranked with
about 13 percent of the acreage.
Wetlands by LLWW Types
The wetland acreage based on LLWW classification was 9,268 acres (excluding ponds) or
9,623.5 acres including ponds (Table 4). Some waterbodies in the 10-20 acre size range that
were classified as palustrine unconsolidated bottoms on the NWI maps were reclassified as lakes
since they are likely deeper than 6.6 feet at low water. This reduced the wetland acreage of the
Hackensack watershed by about 27 acres (see Table 3).
24
Since the Hackensack Meadowlands is the most prominent wetland in the watershed, it was not
surprising that most (56%) of the wetland acreage was associated with the estuary (estuarine
landscape position; Map 2). This figure included tidal freshwater wetlands contiguous with salt
and brackish marshes of the estuary. Nearly 25 percent ot the watershed’s wetland acreage was
associated with rivers and streams and almost 5 percent contiguous with lakes (lentic). Eleven
percent of the wetland acreage was represented by terrene wetlands (headwater stream source
and isolated types), with the remaining 4 percent being ponds.
From the landform perspective, basin wetlands were most extensive, accounting for 57 percent
of the wetland acreage (excluding ponds; Map 3 and Map 4). Many of these wetlands were
estuarine wetlands whose tidal sheet flow has been diminished somewhat due to road
construction (causeways and bridges). Fringe wetlands were second-ranked comprising 26
percent of the acreage. Flats made up 12 percent of the landform acreage, while floodplains
associated with rivers accounted for four percent and slopes comprised one percent.
Considering water flow path, 61 percent of the wetland acreage was bidirectional-tidal and 26
percent was throughflow. Outflow types accounted for only seven percent of the acreage and
nearly five percent was isolated. Almost two percent of the acreage was classified as
bidirectional (associated with lakes/reservoirs) while 276 acres of the throughflow ponds were
associated with lake/reservoir basins.
For the 347 ponds identified (355.7 acres), nearly 70 percent of the acreage was either
throughflow or isolated (31.7% throughflow-perennial, 2.8% throughflow-intermittent, and
34.5% isolated). About 16 percent of the pond acreage had bidirectional water flow and all but
0.2 acres of this was tidally influenced. Outflow ponds accounted for 14 percent of the pond
acreage and only one percent of the pond acreage was subjected to inflow.
25
Table 3. Wetlands classified by NWI types for the Hackensack River watershed.
NWI Wetland Type Acreage % of Total Acreage
Estuarine Wetlands
Emergent 4,019.9
Emergent/Scrub-Shrub 13.8
(subtotal Emergent) (4,033.7) 41.8
Scrub-Shrub 1.6 <0.1
Unconsolidated Shore 1,212.1 12.6
--------------------------------------- -------------- ------
Estuarine Subtotal 5,247.4 54.4
Palustrine Wetlands
Emergent 483.7
Emergent/Scrub-Shrub 116.7
(subtotal Emergent) (600.4) 13.6
Forested, Broad-leaved Deciduous 3,033.5
Forested, Mixed 2.6
Forested, Needle-leaved Evergreen 2.6
Forested, Dead 80.3
Forested/Scrub-Shrub 49.0
Forested/Emergent 29.6
(subtotal Forested) (3,197.5) 33.1
Scrub-Shrub, Deciduous 102.8
Scrub-Shrub/Emergent 43.3
Scrub-Shrub/Forested 75.2
(subtotal Scrub-Shrub) (221.3) 2.3
Unconsolidated Bottom 375.6
Unconsolidated Shore 7.3
(subtotal nonvegetated) (382.9) 4.0
--------------------------------------------- ------------ ------
Palustrine Subtotal 4,402.1 45.6
GRAND TOTAL (ALL WETLANDS) 9,649.5
26
Table 4. Wetlands in the Hackensack River watershed classified by LLWW types.
Landscape Position Landform Water Flow Acreage
Estuarine (ES) Fringe (FR) Bidirectional-tidal (BT) 2,185.7
Basin (BA) Bidirectional-tidal (BT) 3,193.9
Island (IL) Bidirectional-tidal (BT) 1.8
Total Estuarine 5,381.4
Lentic (LE) Basin (BA) Bidirectional (BI) 55.5
Throughflow (TH) 135.8
(subtotal) (191.3)
Flat (FL) Bidirectional (BI) 62.9
Isolated (IS) 3.3
Throughflow (TH) 75.4
(subtotal) (141.6)
Fringe (FR) Bidirectional (BI) 55.7
Throughflow (TH) 61.1
(subtotal) (116.8)
Total Lentic 449.7
Lotic River (LR) Floodplain (FP) Throughflow (TH) 382.7
Fringe (FR) Bidirectional-tidal (BT) 79.5
Throughflow (TH) 6.9
Total Lotic River 469.1
Lotic Stream (LS) Basin (BA) Bidirectional-tidal (BT) 126.7
Throughflow (TH) 1,140.5
(subtotal) (1,267.2)
Flat (FL) Bidirectional-tidal (BT) 35.5
Throughflow (TH) 592.1
(subtotal) (627.6)
Fringe (FR) Throughflow (TH) 5.1
Slope (SL) Throughflow (TH) 7.7
Total Lotic Stream 1,907.6
Terrene (TE) Basin (BA) Isolated (IS) 270.1
Outflow (OU) 368.9
(subtotal) (639.0)
Flat (FL) Isolated (IS) 107.8
Outflow (OU) 229.9
(subtotal) (337.7)
Slope (SL) Isolated (IS) 42.4
Outflow (OU) 40.9
(subtotal) (83.3)
Total Terrene 1,060.0
TOTAL LLWW Types* 9,267.8
*Does not include 347 ponds that totaled 355.7 acres.
27
Preliminary Assessment of Wetland Functions
The results for each wetland function for the Hackensack River watershed are given in Table 5.
Refer to the maps for locations of these wetlands.
Nearly all of the remaining wetland acreage (>95%) in the watershed was deemed potentially
significant for surface water detention and sediment and other particulate retention. Three of the
other functions were predicted to be performed by more than 80 percent of the acreage: nutrient
transformation (84%), provision of other wildlife habitat (83%), and conservation of biodiversity
(82%), with a fourth function – provision of fish and shellfish habitat – rated just below 80
percent (79.5%). Over half of the conservation of biodiversity function was attributed to the
presence of the Hackensack Meadowlands – one of the largest remaining urban wetlands in the
northeastern United States and one that is located in a key position along the Atlantic Flyway and
therefore vitally important for migratory birds. Over 250 species of birds have been observed in
these wetlands. Other wetlands recognized as important for biodiversity included large
complexes greater than 100 acres, headwater wetlands, beaver-influenced wetlands, lakeside
wetlands, wetlands in large complexes along rivers and streams, freshwater tidal wetlands, and
potential woodland vernal pools. The Hackensack watershed wetlands also provided habitat for
waterfowl and other waterbirds at significant levels (71%). An additional 1,744 acres along
streams (18% of the acreage) were rated as important for fish and shellfish by providing shade
over streams. Over 70 percent of the wetland acreage was predicted to be important for
shoreline stabilization, while 58 percent was significant for coastal storm surge detention. Only
30 percent of the wetland acreage was located in headwater positions that serve to maintain
streamflow.
28
Table 5. Predicted wetland functions for the Hackensack River watershed. Click on maps to
view potential wetlands of significance for each function.
Predicted
Function Level Acreage Percent of Wetlands
Surface Water Detention High 7740.1 80.4
(Map 5) Moderate 1746.7 18.2
Total 9486.8 98.6
Streamflow Maintenance High 1118.4 11.6
(Map 6) Moderate 1795.9 18.7
Total 2914.3 30.3
Nutrient Transformation High 6687.5 69.5
(Map 7) Moderate 1367.0 14.2
Total 8054.5 83.7
Sediment and Other
Particulate Retention High 6998.3 72.7
(Map 8) Moderate 2204.4 22.9
Total 9202.7 95.6
Coastal Storm Surge
Detention (Map 9) High 5623.1 58.4
Shoreline Stabilization High 7034.6 73.1
(Map 10) Moderate 38.1 0.4
Total 7072.7 73.5
Fish and Shellfish Habitat High 1751.8 18.2
(Map 11) Moderate 4132.8 42.9
Shading 1774.6 18.4
Total 7659.2 79.5
Waterfowl and Waterbird
Habitat (Map 12) High 1907.5 19.8
Moderate 3827.8 39.8
Wood Duck 1122.5 11.7
Total 6857.8 71.3
Other Wildlife Habitat High (large complex) 5790.3 60.2
(Map 13) High (small diverse wetland) 864.3 9.0
Moderate 1401.7 14.6
Total 8056.3 83.8
29
Table 5 (cont’d).
Conservation of
Biodiversity (Map 14) 100-acre + wetland complex 721.7 7.5
Beaver-influenced wetland 14.1 0.1
Meadowlands wetlands 5238.5 54.4
Estuarine emergent wetland
(not Phragmites) 5.1 0.1
Headwater wetland 1004.4 10.4
Lentic Fringe or Basin
wetland 220.7 2.3
Lotic wetland complex 593.6 6.2
Seasonally flooded-tidal
wetland (not Phragmites) 85.3 0.9
Possible vernal pool 2.5 <0.1
Total 7885.9 81.9
30
Remotely-sensed Indices of “Natural Habitat Integrity���
The generally poor condition of the Hackensack watershed is reflected in the natural habitat
integrity index scores (Table 6). The composite index score of 0.20 indicates a significantly
modified watershed which is no surprise given that three-quarters of the watershed is urbanized
(Map 15). The overall landscape is typically devoid of natural vegetation, with only 25 percent
of the watershed in some kind of “natural cover” in 1995 (natural cover index score of 0.25).
The remaining vegetated regions of the watershed are located in the Meadowlands, around
Oradell Reservoir, around a number of streams (including Overpeck Creek), and in headwater
positions in the northern portion of the watershed.
The predominant urban-suburban landscape generated low scores for the habitat extent indices
(Table 6). About 35 percent of the 100m river-stream corridor was colonized by vegetation
(Map 16), whereas 27 percent of the 100m buffer around mapped wetlands was in natural cover.
The pond and lake buffer appeared to be in somewhat better condition with 44 percent vegetated.
The watershed has lost an estimated 64 percent of its original wetlands and as of 1995, only 36
percent of pre-settlement wetland acreage remained (as reflected by the wetland extent index
score of 0.36). In contrast, waterbodies have increased due to human activities (as reflected by a
standing waterbody extent index score of 1.0). Numerous ponds, reservoirs (e.g., Oradell
Reservoir), and dammed lakes have been built in the watershed since European settlement.
As expected, the aquatic resources within the watershed have been significantly disturbed and
the high disturbance index scores for wetland disturbance and habitat fragmentation by roads
bear this out. Fifty-nine percent of the wetlands altered to some degree. Road construction and
accompanying urban and suburban development has left the Hackensack watershed a fragmented
landscape with only remnants of its original natural habitat in place. In addition, 16 percent of
the river/stream miles have been dammed and 33 percent of the stream miles have been
channelized.
31
Table 6. Scores for remotely-sensed indices of “natural habitat integrity” for the Hackensack
River watershed. *Note: The scores for these indices reflect the percent of the subject area that
is in “natural vegetation.”
Index Score
Habitat Extent Indices
Natural Cover Index (Map 15)* 0.25
River/Stream Corridor Integrity Index (Map 16)* 0.35
Wetland Buffer Integrity Index* 0.27
Pond/Lake Buffer Integrity Index* 0.44
Wetland Extent Index 0.36
Standing Waterbody Extent Index 1.00
Habitat Disturbance Indices
Dammed River/Stream Flowage Index (Map 16) 0.16
Channelized Stream Length Index 0.33
Wetland Disturbance Index 0.59
Habitat Fragmentation by Road Index 0.51
Composite Index 0.20
32
Subbasin Findings
The detailed findings for each subbasin are given in a series of tables in Appendix B. Subbasins
are listed alphabetically. Highlights are given below and in Tables 7 through 11. (Note: Totals
for each subbasin may differ from those reported in an earlier report on the Hackensack
Meadowlands District wetlands because the subbasins may include an area slightly larger than
that contained within the District).
Wetland Characterization
Wetlands by NWI Types
Three subbasins contained the majority of the watershed’s wetland acreage due to the abundance
of estuarine wetlands: Hackensack River Route 3 to Bellman’s Creek, Hackensack River Amtrak
Bridge to Route 3, and Berry’s Creek below Paterson Avenue (Table 7). Combined these
subbasins accounted for 40 percent of the total wetland acreage and 72 percent of the salt and
brackish wetland acreage. Palustrine wetlands were best represented in three subbasins with
each having more than 500 acres of these types: Hackensack-Nauranshaun Confluence,
Hackensack River Oradell to Tappan Bridge, and De Forest Lake. Their freshwater wetland
acreage comprised 37 percent of the watershed’s palustrine acreage.
Wetlands by LLWW Types
The Hackensack-Nauranshaun Confluence subbasin had the most acreage of wetlands associated
with reservoirs and lakes (lentic wetlands) and also ranked high in the extent of streamside
wetlands (lotic stream) and terrene wetlands (Table 8). Lotic river wetlands were best
represented in three subbasins: Hackensack River above Tappan Bridge, Pascack Brook above
Westwood Gage, and Hackensack River Fort Lee to Oradell Gage. They accounted for 76
percent of the watershed’s riverside wetlands. Four subbasins had more than 200 acres of
streamside wetlands (lotic stream), with Berry’s Creek above Paterson Avenue will just slightly
fewer acres (196). Terrene wetlands were most extensive in Hackensack River Oradell to
Tappan Bridge while three other subbasins had more than 100 acres of these types. Estuarine
wetlands were most abundant in three subbasins (same as listed by NWI types).
33
Table 7. Wetland acreage summaries by NWI system for subbasins of the Hackensack River watershed. The percent of each subbasin
occupied by wetlands is given along with the percent of the Hackensack’s wetlands that these wetlands represent and a ranking of
subbasins relative to wetland acreage.
Subbasin Estuarine Palustrine Total Percent Percent of Rank
Acreage Acreage Acreage of Subbasin Hackensack
Wetland Area
Berry’s Creek above Paterson Avene 83.8 379.5 463.3 12.1 4.8 9
Berry’s Creek below Paterson Avenue 909.3 42.1 951.4 24.8 9.9 3
Coles Brook/Van Saun Mill Brook -- 123.7 123.7 2.8 1.3 16
De Forest Lake -- 506.0 506.0 2.9 5.2 8
Dwars Kill -- 408.0 408.0 11.6 4.2 10
Hackensack-Nauranshaun Confluence -- 596.4 596.4 5.5 6.2 6
Hackensack R. – Amtrak Bridge to Rt. 3 1431.3 47.9 1479.2 23.2 15.3 1
Hackensack R. – Bellman’s Creek to
Fort Lee Road 651.7 55.6 707.3 11.3 7.3 4
Hackensack R. below Amtrak Bridge 563.1 89.9 653.0 9.6 6.8 5
Hackensack R. – Ft. Lee to Oradell Gage -- 118.0 118.0 3.0 1.2 17
Hackensack R. – Rt. 3 to Bellman’s Creek 1445.6 9.6 1455.2 28.4 15.1 2
Hackensack R. above Tappan Bridge -- 397.4 397.4 5.3 4.1 11
Hackensack R. – Oradell to Tappan Bridge -- 510.6 510.6 6.5 5.3 7
Hirshfeld Brook -- 30.0 30.0 1.0 0.3 19
Overpeck Creek 162.6 149.5 312.1 2.8 3.2 13
Pascack Brook above Westwood Gage -- 301.7 301.7 3.3 3.1 14
Pascack Brook below Westwood Gage -- 337.6 337.6 6.2 3.5 12
Tenakill Brook -- 202.3 202.3 3.6 2.1 15
Upper Pascack Brook -- 96.4 96.4 2.1 1.0 18
34
Table 8. Wetlands by landscape position for subbasins of the Hackensack River watershed.
Subbasin Estuarine Lentic Lotic River Lotic Stream Terrene Total
Acreage Acreage Acreage Acreage Acreage Acres
Berry’s Creek above Paterson Avene 102.6 -- 3.0 196.3 157.0 458.9
Berry’s Creek below Paterson Avenue 922.9 -- -- -- 1.7 924.6
Coles Brook/Van Saun Mill Brook -- -- 3.9 92.6 19.8 116.3
De Forest Lake -- 45.1 -- 280.0 114.0 439.1
Dwars Kill -- 84.8 -- 240.8 77.3 402.9
Hackensack-Nauranshaun Confluence -- 211.5 23.9 204.2 120.2 559.8
Hackensack R. – Amtrak Bridge to Rt. 3 1447.4 -- -- 1.6 13.5 1462.5
Hackensack R. – Bellman’s Creek to
Fort Lee Road 675.9 -- -- 16.7 5.6 698.2
Hackensack R. below Amtrak Bridge 609.1 -- -- -- 9.1 618.2
Hackensack R. – Ft. Lee to Oradell Gage 1.0 -- 79.8 13.5 15.4 109.7
Hackensack R. – Rt. 3 to Bellman’s Creek 1453.7 -- -- -- -- 1453.7
Hackensack R. above Tappan Bridge -- 5.8 148.2 145.2 71.0 370.2
Hackensack R. – Oradell to Tappan Bridge -- 3.3 31.4 248.3 205.8 488.8
Hirshfeld Brook -- -- -- 26.34 -- 26.3
Overpeck Creek 168.8 1.3 0.5 82.0 30.2 282.8
Pascack Brook above Westwood Gage -- 27.6 36.7 132.7 80.4 277.4
Pascack Brook below Westwood Gage -- 41.8 129.6 123.4 26.2 321.0
Tenakill Brook -- 28.6 11.6 102.7 43.9 186.8
Upper Pascack Brook -- -- 0.6 1.3 68.9 70.8
35
Preliminary Assessment of Wetland Functions
It is no surprise that subbasins with the most wetland acreage tended to have the most acreage of
wetlands significant for wetland functions, especially those comprising the bulk of wetlands in
the Hackensack Meadowlands: Hackensack River Amtrak Bridge to Route 3, Hackensack River
Route 3 to Bellman’s Creek, and Berry’s Creek below Paterson Avenue. Wetlands located in
headwater positions are important for streamflow maintenance. These wetlands were most
abundant in the Hackensack-Nauranshaun Confluence and De Forest Lake subbasins; they
represented about 30 percent of the wetlands important for this function. Other subbasins with
substantial acreage of headwater wetlands included Hackensack River 0radell to Tappan Bridge,
Hackensack River above Tappan Bridge, Pascack Brook below Westwood Gage, and Dwars Kill
which when combined accounted for 44 percent of the wetlands important for streamflow
maintenance. Wetlands in the Hackensack River Ft. Lee to Oradell Gage subbasin represented
12 percent of the wetlands predicted as significant for sediment and other particulate retention.
Remotely-sensed Indices of “Natural Habitat Integrity”
Examining the composite index scores, five subbasins have more “natural habitat” relative to
their size than the rest (Table 11): Dwars Kill, Hackensack River Oradell to Tappan Bridge, De
Forest Lake, Hackensack-Nauranshaun Confluence, and Hackensack River above Tappan
Bridge. All of these subbasins had composite score of 0.30 or more. Dwars Kill had the highest
composite score (0.53) which was approaching twice the value of the next ranked subbasin
(Hackensack River Oradell to Tappan Bridge). Six subbasins had more than 30 percent of their
land area in natural vegetation (NC score > 0.30). Hackensack River Amtrak Bridge to Route 3
and Dwars Kill had the highest scores. River and stream corridor integrity was best in Dwars
Kill, but also was fairly good in six other subbasins having scores > 0.40. Wetland buffers were
in the best condition in six subbasins having scores near 0.50 and above. Hackensack River
above Tappan Bridge had the highest rating (0.60) with 60 percent of its 100m buffer being
vegetated. Four subbasins had pond and lake buffer scores above 0.50, with Dwars Kill ranked
first. The wetland extent index scores were high for many subbasins, especially Tenakill Brook,
Pascack Brook below Westwood Gage, and Coles Brook/Van Saun Mill Brook with scores
above 0.80. Surprisingly, the Hackensack River Fort Lee to Oradell Gage subbasin appeared to
have all of its historic wetlands (based on a comparison with the 1880s data). The standing
waterbody extent index was assumed to be 1.0 for all subbasins.
For the disturbance indices, Hackensack River Fort Lee to Oradell Gage had the most dammed
stream flowage with all of its streams dammed (Table 11). Three others had dammed stream
flowage index scores above 0.24. Three subbasins had all their streams channelized: Berry’s
Creek above Paterson Avenue, Hackensack River Amtrak Bridge to Route 3, and Hackensack
River below Amtrak Bridge. Numerous subbasins had more than 50 percent of their wetlands
altered by ditching, impoundment, or excavation, with Berry’s Creek below Paterson Avenue
being most impacted (WD score of 0.87). The least wetland disturbance was noted in subbasins
of the upper Hackensack watershed: Dwars Kill, Coles Brook/Van Saun Mill Brook and
Hackensack River Fort Lee to Oradell Gage. Habitat fragmentation of the watershed by roads
was extensive in most subbasins. Those with the lowest level of fragmentation included Dwars
Kill and Hackensack River above Tappan Bridge.
36
Table 9. Acreage of wetlands identified as potentially significant for various functions within each subbasin. Numbers are rounded
off to nearest acre. (See Appendix B for details)
Subbasin Acres of Wetlands Predicted as Significant for Specific Functions
SWD SFM NT SPR CSD SS FSH WWH OWH CB
Berry’s Creek above Paterson Avenue 449 6 458 447 265 294 216 246 458 432
Berry’s Creek below Paterson Avenue 951 -- 924 951 923 924 911 920 924 873
Coles Brook/Van Saun Mill Brook 124 117 116 112 2 96 68 19 116 90
De Forest Lake 490 416 438 474 -- 348 296 302 438 327
Dwars Kill 393 267 403 344 -- 326 230 139 403 374
Hackensack-Nauranshaun Confluence 596 431 560 573 -- 449 351 327 560 302
Hackensack R. – Amtrak Bridge to Rt. 3 1476 5 687 1476 1447 673 1451 1401 687 1438
Hackensack R. – Bellman’s Creek to Ft.Lee Road 707 17 569 705 676 563 670 627 569 666
Hackensack R. below Amtrak Bridge 647 -- 618 650 609 611 619 584 618 533
Hackensack R. – Ft. Lee to Oradell Gage 118 22 110 110 79 93 100 97 110 87
Hackensack R. – Rt. 3 to Bellman’s Creek 1455 -- 1163 1455 1454 1163 1450 1375 1163 1421
Hackensack R. above Tappan Bridge 394 350 370 354 -- 309 297 217 370 332
Hackensack R. – Oradell to Tappan Bridge 445 353 489 380 -- 324 203 62 489 282
Hirshfeld Brook 30 30 26 30 -- 26 25 22 26 23
Overpeck Creek 312 113 269 307 169 237 249 121 269 135
Pascack Brook above Westwood Gage 298 241 277 265 -- 200 132 107 278 134
Pascack Brook below Westwood Gage 338 304 321 325 -- 293 227 214 321 279
Tenakill Brook 178 177 187 169 -- 143 106 29 187 127
Upper Pascack Brook 86 65 71 74 -- 2 16 50 71 30
Codes: SWD-surface water detention, SFM-streamflow maintenance, NT-nutrient transformation, SPR-sediment and other particulate
retention, CSD-coastal storm surge detention, SS-shoreline stabilization, FSH-provision of fish and shellfish habitat, WWH-provision
of waterfowl and waterbird habitat, OWH-provision of other wildlife habitat, and CB-conservation of biodiversity.
37
Table 10. Percent of watershed’s wetlands identified as significant for various functions that are located in each subbasin.
Subbasin Percent of Hackensack Watershed’s Significant Wetlands for Functions
SWD SFM NT SPR CSD SS FSH WWH OWH CB
Berry’s Creek above Paterson Avenue 4.7 0.2 5.7 4.9 4.7 4.2 2.8 3.6 5.7 5.5
Berry’s Creek below Paterson Avenue 10.0 -- 11.5 10.3 16.4 13.1 11.9 13.4 11.5 11.1
Coles Brook/Van Saun Mill Brook 1.3 4.0 1.4 1.2 <0.1 1.4 0.9 0.3 1.4 1.1
De Forest Lake 5.2 14.3 5.4 5.2 -- 4.9 3.9 4.4 5.4 4.1
Dwars Kill 4.1 9.2 5.0 3.7 -- 4.6 3.0 2.0 5.0 4.7
Hackensack-Nauranshaun Confluence 6.3 14.8 7.0 6.2 -- 6.3 4.6 4.8 6.9 3.8
Hackensack R. – Amtrak Bridge to Rt. 3 15.6 0.2 8.5 16.0 25.7 9.5 18.9 20.4 8.5 18.2
Hackensack R. – Bellman’s Creek to Ft. Lee Road 7.5 0.6 7.1 7.7 12.0 8.0 8.7 9.1 7.1 8.4
Hackensack R. below Amtrak Bridge 6.8 -- 7.7 7.1 10.8 8.6 8.1 8.5 7.7 6.8
Hackensack R. – Ft. Lee to Oradell Gage 1.2 0.8 1.4 12.0 1.4 1.3 1.3 1.4 1.4 1.1
Hackensack R. – Rt. 3 to Bellman’s Creek 15.3 -- 14.4 15.8 25.9 16.4 18.9 20.0 14.4 18.0
Hackensack R. above Tappan Bridge 4.2 12.0 4.6 3.8 -- 4.4 3.9 3.2 4.6 4.2
Hackensack R. – Oradell to Tappan Bridge 4.7 12.1 6.1 4.1 -- 4.6 2.6 0.9 6.1 3.6
Hirshfeld Brook 0.3 1.0 0.3 0.3 -- 0.3 0.3 0.3 0.3 0.3
Overpeck Creek 3.3 3.9 3.3 3.3 3.0 3.4 3.3 1.8 3.3 1.7
Pascack Brook above Westwood Gage 3.1 8.2 3.4 2.9 -- 2.8 1.7 1.6 3.4 1.7
Pascack Brook below Westwood Gage 3.6 10.4 4.0 3.5 -- 4.1 3.0 3.1 4.0 3.5
Tenakill Brook 1.9 6.1 2.3 1.8 -- 2.0 1.4 0.4 2.3 1.6
Upper Pascack Brook 0.9 2.2 0.9 0.8 -- -- 0.2 0.7 0.8 0.4
Codes: SWD-surface water detention, SFM-streamflow maintenance, NT-nutrient transformation, SPR-sediment and other particulate
retention, CSD-coastal storm surge detention, SS-shoreline stabilization, FSH-provision of fish and shellfish habitat, WWH-provision
of waterfowl and waterbird habitat, OWH-provision of other wildlife habitat, and CB-conservation of biodiversity.
38
Table 11. Remotely-sensed indices of “natural habitat integrity” for subbbasins.
Subbasin Index Scores
NC RSC WB PLB WE SWE DSF CSL WD HFR COMP
Berry’s Creek above Paterson Avene 0.16 0.40 0.12 0.16 0.31 1.00 0.00 1.00 0.61 0.61 0.06
Berry’s Creek below Paterson Avenue 0.31 0.00 0.14 0.10 0.35 1.00 0.00 0.00 0.87 0.72 0.15
Coles Brook/Van Saun Mill Brook 0.08 0.18 0.11 0.15 0.83 1.00 0.00 0.13 0.10 0.58 0.18
De Forest Lake 0.39 0.44 0.51 0.56 0.39 1.00 0.30 0.29 0.66 0.34 0.32
Dwars Kill 0.44 0.64 0.56 0.68 0.70 1.00 0.00 0.09 0.07 0.26 0.53
Hackensack-Nauranshaun Confluence 0.33 0.41 0.47 0.56 0.54 1.00 0.24 0.29 0.41 0.58 0.31
Hackensack R. – Amtrak Bridge to Rt. 3 0.45 0.03 0.04 0.22 0.16 1.00 0.00 1.00 0.55 0.56 0.15
Hackensack R. – Bellman’s Creek to
Fort Lee Road 0.13 0.10 0.07 0.28 0.45 1.00 0.00 0.88 0.72 0.77 0.01
Hackensack R. below Amtrak Bridge 0.16 0.10 0.33 0.41 0.27 1.00 0.00 1.00 0.77 0.82 0.02
Hackensack R. – Ft. Lee to Oradell Gage 0.07 0.33 0.11 0.07 1.00 1.00 1.00 0.03 0.10 0.54 0.13
Hackensack R. – Rt. 3 to Bellman’s Creek 0.31 0.00 0.21 0.15 0.40 1.00 0.00 0.00 0.69 0.91 0.17
Hackensack R. above Tappan Bridge 0.24 0.45 0.61 0.45 0.74 1.00 0.33 0.19 0.72 0.26 0.30
Hackensack R. – Oradell to Tappan Bridge 0.27 0.47 0.50 0.54 0.73 1.00 0.06 0.24 0.63 0.31 0.33
Hirshfeld Brook 0.04 0.12 0.11 0.08 0.73 1.00 0.03 0.36 0.12 0.54 0.12
Overpeck Creek 0.12 0.22 0.34 0.27 0.36 1.00 0.09 0.56 0.36 0.69 0.11
Pascack Brook above Westwood Gage 0.23 0.41 0.26 0.39 0.59 1.00 0.09 0.09 0.41 0.41 0.27
Pascack Brook below Westwood Gage 0.16 0.35 0.19 0.27 0.84 1.00 0.05 0.45 0.18 0.36 0.24
Tenakill Brook 0.15 0.27 0.29 0.33 0.99 1.00 0.01 0.43 0.45 0.38 0.23
Upper Pascack Brook 0.20 0.08 0.49 0.36 0.24 1.00 0.08 0.67 0.34 0.40 0.17
Index Codes: NC-natural cover, RSC-river and stream corridor integrity, WB-wetland buffer integrity, PLB-pond and lake buffer
integrity, WE-wetland extent, SWE-standing waterbody extent, DSF-dammed stream flowage, CSL-channelized stream length, WD-wetland
disturbance, HFR-habitat fragmentation by road, and COMP-composite habitat integrity.
39
Conclusions
The Hackensack River watershed had nearly 9,650 acres of wetlands (including ponds), with
over half (5,445 acres) located in the Hackensack Meadowlands. Estuarine emergent wetlands
were the predominant wetland type comprising 42 percent of the watershed’s wetlands.
Palustrine forested wetlands were next ranked in abundance, accounting for a third of all
wetlands.
From the landscape perspective, about 56 percent of the wetland acreage was associated with the
estuary due to the prominence of the Hackensack Meadowlands. Nearly one-quarter of the
wetland acreage was associated with rivers and streams (roughly 5% and 20%, respectively) and
almost 5 percent contiguous with lakes. Eleven percent of the wetland acreage was represented
by terrene wetlands (headwater stream source and isolated types), with the remaining four
percent being ponds.
From the landform perspective, basin wetlands were most extensive, accounting for 57 percent
of the wetland acreage (excluding ponds). Many of these wetlands were estuarine wetlands
whose tidal sheet flow has been diminished somewhat due to road construction (causeways and
bridges). Fringe wetlands were second-ranked comprising 26 percent of the acreage. Flats made
up 12 percent of the acreage, while floodplains associated with rivers accounted for four percent
and slopes comprised one percent.
Considering water flow path, 61 percent of the wetland acreage was bidirectional-tidal and 26
percent was throughflow. Outflow types (associated mostly with headwater wetlands in the
upper watershed) accounted for only seven percent of the acreage. Nearly five percent of the
wetland acreage was isolated and almost two percent of the acreage was classified as
bidirectional (associated with lakes/reservoirs).
Functionally, nearly all of the remaining wetland acreage (>95%) in the watershed was rated as
potentially significant for surface water detention (e.g., flood storage) and sediment and other
particulate retention (e.g., water quality renovation). Four other functions were predicted to be
performed by 80 percent or more of the acreage: provision of other wildlife habitat, nutrient
transformation, conservation of biodiversity, and provision of fish and shellfish habitat. Over
half of the conservation of biodiversity function was attributed to the presence of the Hackensack
Meadowlands – one of the largest remaining urban wetlands in the northeastern United States.
Other wetlands recognized as important for biodiversity included large complexes greater than
100 acres, headwater wetlands, beaver-influenced wetlands, lakeside wetlands, wetlands in large
complexes along rivers and streams, freshwater tidal wetlands, and potential woodland vernal
pools. About 70 percent of the Hackensack watershed wetlands also provided habitat for
waterfowl and other waterbirds at significant levels and were rated as important for shoreline
stabilization, while 58 percent was significant for coastal storm surge detention. Only 30 percent
of the wetland acreage was located in headwater positions that serve to maintain streamflow.
Analysis of land use patterns in the watershed documented the generally poor condition of the
Hackensack River watershed which is no surprise given that 75 percent of the watershed is
urbanized. Over three centuries of population growth and land and water development in the
40
watershed have taken their toll on the watershed’s natural resources. The overall landscape is
largely devoid of natural vegetation, with only 25 percent of the watershed in some kind of
“natural cover” in 1995. As anticipated given the urban-suburban landscape, stream corridors
and wetland buffers are generally devoid of vegetation: about 35 percent of the 100m river-stream
corridor was colonized by vegetation, whereas 27 percent of the 100m buffer around
mapped wetlands was in natural cover. By 1995, the watershed lost 64% of its original wetlands
and the functions they provided. In contrast, waterbodies have increased due to construction of
ponds, reservoirs, and dammed lakes. The aquatic resources within the watershed have been
significantly altered: 16 percent of the river/stream miles have been dammed, 33 percent of the
stream miles channelized, and 59 percent of the wetlands altered to some degree; pollution by
runoff, discharge of municipal and industrial wastewaters, and other operations have further
degraded the quality of the watershed’s aquatic resources. Road construction and accompanying
urban and suburban development have left the Hackensack watershed a fragmented landscape
with only remnants of its original natural habitat in place.
Information from this study was used to help the Service prepare a conservation strategy for the
Hackensack Meadowlands ecosystem (U.S. Fish and Wildlife Service 2007). Some key
recommendations of this conservation plan were: 1) protect wetlands and their buffers in the
upper Hackensack River watershed, 2) development of a comprehensive remediation and
restoration plan is critical to address problems confronting the Meadowlands ecosystem, 3)
increase the extent and connectivity of upland buffers, and 4) consider designating the
Meadowlands as a marine/estuarine protected area.
41
Acknowledgments
The entire study was funded and conducted pursuant to Congressional directives to support
restoration of the Hackensack Meadowlands (see H.R. 109-90). The initial classification and
mapping, however, was funded by the Service’s strategic mapping initiative of the National
Wetlands Inventory (NWI) Program at the request of Cliff Day, Supervisor of the Service’s New
Jersey Field Office (NJFO). The analysis work and preparation of this report was funded by the
New Jersey Field Office’s Hackensack Meadowlands Initiative (HMI). Stan Hales was project
officer for that portion of the work with Ralph Tiner serving as the principal investigator. We
especially thank Congressman Steve Rothman for his support of the HMI.
All work was done by the Service’s Regional NWI Program. Wetland classification and
photointerpretation were performed by Meaghen Shaffer, Lauren McCubbin, and Lisa Reisner.
Bobbi Jo McClain did LLWW classifications with quality control and final edits by Herb
Bergquist. Mr. Bergquist was also responsible for land use/cover classification and mapping,
GIS analysis, and providing data summaries and maps for this report. Ralph Tiner designed and
coordinated the study, analyzed the results, and prepared the report.
Special thanks to Karen L. Siletti for the use of her figure showing the major waterbodies of the
Hackensack River watershed (Figure 1).
42
References
Able, K.W. and S.M. Hagan. 2003. Impact of common reed, Phragmites australis, on essential
fish habitat: influence on reproduction, embryological development, and larval abundance of
mummichog (Fundulus heteroclitus). Estuaries 26: 40-50.
Anderson, J.R., E. Hardy, J. Roach, and R. Witmer. 1976. A land use and land cover
classification system for use with remote sensor data. U.S. Geological Survey, Washington, DC.
Professional Paper 964.
Benoit, L.K, and R.A. Askins. 1999. Impact of the spread of Phragmites on the distribution of
birds in Connecticut tidal marshes. Wetlands 19: 194-208.
Brinson, M. M. 1993. A Hydrogeomorphic Classification for Wetlands. U.S. Army Corps of
Engineers, Washington, DC. Wetlands Research Program, Technical Report WRP-DE-4.
Buchsbaum, R. 1997. Return of the native or what? Sanctuary 36 (3): 12-15.
Chambers, R.M., L.A. Meyerson, and K. Saltonstall. 1999. Expansion of Phragmites australis
into tidal wetlands of North America. Aquatic Botany 64: 261-273.
Cowardin, L. M., V. Carter, F. C. Golet, and E. T. LaRoe. 1979. Classification of Wetlands and
Deepwater Habitats of the United States. U.S. Fish and Wildlife Service, Washington, DC.
FWS/OBS-79/31.
Cross, D.H. and K.L. Fleming. 1989. Control of Phragmites or common reed. U.S. Fish and
Wildlife Service, Washington, DC. Fish and Wildlife Leaflet 13.4.12.
Freeman, C. Undated. The effects of Phragmites australis on salt marsh nekton. Connecticut
College, New London, CT. Unpublished manuscript (Dr. Linda Deegan, advisor).
Hanson, S.R., D.T. Osgood, and D.J. Yozzo. 2002. Nekton use of a Phragmites australis marsh
on the Hudson River, New York, USA. Wetlands 22: 326-337.
Kiviat, E. 1987. Common reed (Phragmites australis). In: D.Decker and J. Enck (Eds.). Exotic
Plants with Identified Detrimental Impacts on Wildlife Habitats in New York. New York
Chapter, The Wildlife Society, Annandale, NY. pp. 22-30.
Levine, J.M., J.S. Brewer, and M.D. Bertness. 1998. Nutrients, competition and plant zonation
in a New England salt marsh. J. Ecol. 86: 125-136.
Marks, M., B. Lapin, and J. Randall. 1994. Phragmites australis (P. communis): threats,
management, and monitoring. Natural Areas Journal 14: 285-294.
Meyerson, L.A., K. Saltonstall, L. Windham, E. Kiviat, and S. Findlay. 2000. A comparison of
Phragmites australis in freshwater and brackish marsh environments in North America.
43
Wetlands Ecology and Management 8: 89-103.
Mitsch, W.J. and J.G. Gosselink. 2000. Wetlands. John Wiley and Sons, Inc., New York, NY.
Orson, R.A., R.S. Warren, and W.A. Niering. 1987. Development of a tidal marsh in a New
England river valley. Estuaries 10: 20-27.
Roman, C.T., W.A. Niering, and R.S. Warren. 1984. Salt marsh vegetation changes in response
to tidal restrictions. Environmental Management 8: 141-150.
Rozas, L.P. 1992. Comparison of nekton habitats associated with pipeline canals and natural
channels in Louisiana salt marshes. Wetlands 12: 136-146.
Saltonstall, K. 2002. Cryptic invasion by a non-native genotype of the common reed, Phragmites
australis, into North America. Proceedings of the Natural Academy of Sciences of the United
States of America. Vol. 99 (4): 2445-2449.
Tiner, R.W. 1997b. NWI Maps: What They Tell Us. National Wetlands Newsletter 19(2): 7-12.
(Copy available from USFWS, ES-NWI, 300 Westgate Center Drive, Hadley, MA 01035)
Tiner, R.W. 2003a. Dichotomous Keys and Mapping Codes for Wetland Landscape Position,
Landform, Water Flow Path, and Waterbody Type Descriptors. U.S. Fish and Wildlife Service,
Northeast Region, Hadley, MA. September 2003.
http://library.fws.gov/wetlands/dichotomouskeys0903.pdf
Tiner, R.W. 2003b. Correlating Enhanced National Wetlands Inventory Data With Wetland
Functions for Watershed Assessments: A Rationale for Northeastern U.S. Wetlands. U.S. Fish
and Wildlife Service, Northeast Region, Hadley, MA.
http://www.fws.gov/nwi/pubs_reports/HGMReportOctober2003.pdf
Tiner, R.W. 2004. Remotely-sensed indicators for monitoring the general condition of “natural
habitat” in watersheds: an application for Delaware’s Nanticoke River watershed. Ecological
Indicators 4: 227-243.
Tiner, R.W. 2005a. Assessing cumulative loss of wetland functions in the Nanticoke River
watershed using enhanced National Wetlands Inventory data. Wetlands 25(2): 405-419.
Tiner, R.W. 2005b. In Search of Swampland: A Wetland Sourcebook and Field Guide. Revised
and Expanded 2nd Edition. Rutgers University Press, New Brunswick, NJ.
Tiner, R.W., J.Q. Swords, and B.J. McClain. 2002. Wetland Status and Trends for the
Hackensack Meadowlands. An Assessment Report from the U.S. Fish and Wildlife Service’s
National Wetlands Inventory Program. U.S. Fish and Wildlife Service, Northeast Region,
Hadley, MA. http://library.fws.gov/wetlands/hackensack.pdf
U.S. Fish and Wildlife Service. 2007. The Hackensack Meadowlands Initiative. Preliminary
44
Conservation Planning for the Hackensack Meadowlands, Hudson and Bergen Counties, New
Jersey. New Jersey Field Office report, Pleasantville, NJ.
Weinstein, M.P., and J.H. Balletto. 1999. Does the common reed, Phragmites australis, affect
essential fish habitat? Estuaries 22: 793-802.
Appendices
46
Appendix A. Coding for LLWW descriptors from “Dichotomous Keys and Mapping Codes for
Wetland Landscape Position, Landform, Water Flow Path, and Waterbody Type Descriptors”
(Tiner 2003a).
47
Section 4. Coding System for LLWW Descriptors
The following is the coding scheme for expanding classification of wetlands and waterbodies
beyond typical NWI classifications. When enhancing NWI maps/digits, codes should be applied
to all mapped wetlands and deepwater habitats (including linears). At a minimum, landscape
position (including lotic gradient), landform, and water flow path should be applied to wetlands,
and waterbody type and water flow path to water to waterbodies. Wetland and deepwater habitat
data for specific estuaries, lakes, and river systems could be added to existing digital data
through use of geographic information system (GIS) technology.
Codes for Wetlands
Wetlands are typically classified by landscape position, landform, and water flow path.
Landforms are grouped according to Inland types and Coastal types with the latter referring to
tidal wetlands associated with marine and estuarine waters. Use of other descriptors tends to be
optional. They would be used for more detailed investigations and characterizations.
Landscape Position
ES Estuarine
LE Lentic
LR Lotic river
LS Lotic stream
MA Marine
TE Terrene
Lotic Gradient
1 Low
2 Middle
3 High
4 Intermittent
5 Tidal
6 Dammed
a lock and dammed
b run-of-river dam
c beaver
d other dammed
7 Artificial (ditch)
48
Lentic Type
1 Natural deep lake (see also Pond codes for possible specific types)
a main body
b open empbayment
c semi-enclosed embayment
d barrier beach lagoon
2 Dammed river valley lake
a reservoir
b hydropower
c other
3 Other dammed lake
a former natural
b artificial
4 Excavated lake
a quarry lake
5 Other artificial lake
Estuary Type
1 Drowned river valley estuary
a open bay (fully exposed)
b semi-enclosed bay
c river channel
2 Bar-built estuary
a coastal pond-open
b coastal pond-seasonally closed
c coastal pond-intermittently open
d hypersaline lagoon
3 River-dominated estuary
4 Rocky headland bay estuary
a island protected
5 Island protected estuary
6 Shoreline bay estuary
a open (fully exposed)
b semi-enclosed
7 Tectonic
a fault-formed
b volcanic-formed
8 Fjord
9 Other
49
Inland Landform
SL Slope
SLpa Slope, paludified
IL Island*
ILde Island, delta
ILrs Island, reservoir
ILpd Island, pond
FR Fringe*
FRil Fringe, island*
FRbl Fringe, barrier island
FRbb Fringe, barrier beach
FRpd Fringe, pond
FRdm Fringe, drowned river mouth
FP Floodplain
FPba Floodplain, basin
FPox Floodplain, oxbow
FPfl Floodplain, flat
FPil Floodplain, island
IF Interfluve
IFba Interfluve, basin
IFfl Interfluve, flat
BA Basin
BAcb Basin, Carolina bay
BApo Basin, pocosin
BAcd Basin, cypress dome
BApp Basin, prairie pothole
BApl Basin, playa
BAwc Basin, West Coast vernal pool
BAid Basin, interdunal
BAwv Basin, woodland vernal
BApg Basin, polygonal
BAsh Basin, sinkhole
BApd Basin, pond
BAgp Basin, grady pond
BAsa Basin, salt flat
BAaq Basin, aquaculture (created)
BAcr Basin, cranberry bog (created)
BAwm Basin, wildlife management (created)
50
BAip Basin, impoundment (created)
BAfe Basin, former estuarine wetland
BAff Basin, former floodplain
BAfi Basin, former interfluve
BAfo Basin, former floodplain oxbow
BAdm Basin, drowned river-mouth
FL Flat
FLsa Flat, salt flat
FLff Flat, former floodplain
FLfi Flat, former interfluve
*Note: Inland slope wetlands and island wetlands associated with rivers, streams, and
lakes are designated as such by the landscape position classification (e.g., lotic river, lotic
stream, or lentic), therefore no additional terms are needed here to convey this
association.
Coastal Landform
IL Island
ILdt Island, delta
ILde Island, ebb-delta
ILdf Island, flood-delta
ILrv Island, river
ILst Island, stream
ILby Island, bay
DE Delta
DEr Delta, river-dominated
DEt Delta, tide-dominated
DEw Delta, wave-dominated
FR Fringe
FRal Fringe, atoll lagoon
FRbl Fringe, barrier island
FRbb Fringe, barrier beach
FRby Fringe, bay
FRbi Fringe, bay island
FRcp Fringe, coastal pond
FRci Fringe, coastal pond island
FRhl Fringe, headland
FRoi Fringe, oceanic island
FRlg Fringe, lagoon
FRrv Fringe, river
51
FRri Fringe, river island
FRst Fringe, stream
FRsi Fringe, stream island
BA Basin
BAaq Basin, aquaculture (created)
BAid Basin, interdunal (swale)
BAst Basin, stream
BAsh Basin, salt hay production (created)
BAtd Basin, tidally restricted/road (not a management area)
BAtr Basin, tidally restricted/railroad (not a management area)
BAwm Basin, wildlife management (created)
BAip Basin, impoundment (created)
Water Flow Path
PA Paludified
IS Isolated
IN Inflow
OU Outflow
OA Outflow-artificial*
OP Outflow-perennial
OI Outflow-intermittent
TH Throughflow
TA Throughflow - artificial*
TN Throughflow - entrenched
TI Throughflow - intermittent
BI Bidirectional Flow - nontidal
BT Bidirectional Flow - tidal
*Note: To be used with wetlands connected to streams by ditches.
Other Modifiers (apply at the end of the code as appropriate)
br barren
bv beaver
ch channelized flow
cl coastal island (wetland on an island in an estuary or ocean including barrier
islands)
cr cranberry bog
dd drainage divide
dr partly drained
ed freshwater wetland discharging directly into an estuary
fe former estuarine wetland
fg fragmented
fm floating mat
52
gd groundwater-dominated (apply to Water Flow Path only)
hi severely human-induced
hw headwater
li lake island (wetland associated with a lake island)
md freshwater wetland discharging directly into marine waters
ow overwash
pi pond island border
ri river island (wetland associated with a river island)
sd surface water-dominated (apply to Water Flow Path only)
sf spring-fed
ss subsurface flow
td tidally restricted/road
tr tidally restricted/railroad
(Note: "ho" was formerly used to indicate human-induced outflow brought about by ditch
construction; now this is addressed by the water flow path "OA" Outflow-Artificial.)
Codes for Waterbodies
Besides Waterbody Type, waterbodies can be classified by water flow path (for lakes and
ponds), estuary hydrologic type (for estuaries), and tidal range types (for estuaries and oceans).
Waterbody Type
RV River
1 low gradient
a connecting channel
b canal
2 middle gradient
a connecting channel
3 high gradient
a waterfall
b riffle
c pool
4 intermittent gradient
5 tidal gradient
6 dammed gradient
a lock and dammed
b run-of-river dammed
c other dammed
ST Stream
1 low gradient
a connecting channel
2 middle gradient
53
a connecting channel
3 high gradient
a waterfall
b riffle
c pool
4 intermittent gradient
5 tidal gradient
6 dammed
a lock and dammed
b run-of-river dammed
c beaver dammed
d other dammed
7 artificial
a connecting channel
b ditch
LK Lake
1 natural lake (see also Pond codes for possible specific types)
a main body
b open empbayment
c semi-enclosed embayment
d barrier beach lagoon
2 dammed river valley lake
a reservoir
b hydropower
c other
3 other dammed lake
a former natural
b artificial
4 other artificial lake
(Consider using a modifier to highlight specific lakes as needed, especially the Great
Lakes, e.g., LK1E for Lake Erie or LK2O for Lake Ontario, and Lake Champlain, LK1C)
EY Estuary
1 drowned river valley estuary
a open bay (fully exposed)
b semi-enclosed bay
c river channel
2 bar-built estuary
a coastal pond-open
b coastal pond-seasonally closed
c coastal pond-intermittently open
d hypersaline lagoon
3 river-dominated estuary
54
4 rocky headland bay estuary
a island protected
5 island protected estuary
6 shoreline bay estuary
a open (fully exposed)
b semi-enclosed
7 tectonic
a fault-formed
b volcanic-formed
8 fjord
9 other
Note: If desired, you can also designate river channel (rc), stream channel (sc),and inlet
channel (ic) by modifiers. Examples: EY1rc = Drowned River Valley Estuary river
channel; EY2ic= Bar-built estuary inlet channel. If not, simply classify all estuarine
water as a single type, e.g., EY1 for Drowned River Valley or EY2 for Bar-built Estuary.
OB Ocean or Bay
1 open (fully exposed)
2 semi-protected oceanic bay
3 atoll lagoon
4 other reef-protected waters
5 fjord
PD Pond
1 natural
a bog
b woodland-wetland
c woodland-dryland
d prairie-wetland (pothole)
e prairie-dryland (pothole)
f playa
g polygonal
h sinkhole-woodland
i sinkhole-prairie
j Carolina bay
k pocosin
l cypress dome
m vernal-woodland
n vernal-West Coast
o interdunal
p grady
q floodplain
r other
2 dammed/impounded
a agriculture
55
a1 cropland
a2 livestock
a3 cranberry
b aquaculture
b1 catfish
b2 crayfish
c commercial
c1 commercial-stormwater
d industrial
d1 industrial-stormwater
d2 industrial-wastewater
e residential
e1 residential-stormwater
f sewage treatment
g golf
h wildlife management
i other recreational
o other
q floodplain
3 excavated
a agriculture
a1 cropland
a2 livestock
a3 cranberry
b aquaculture
b1 catfish
b2 crayfish
c commercial
c1 commercial-stormwater
d industrial
d1 industrial-stormwater
d2 industrial-wastewater
e residential
e1 residential-stormwater
f sewage treatment
g golf
h wildlife management
i other recreational
j mining
j1 sand/gravel
j2 coal
o other
q floodplain
4 beaver
5 other artificial
56
Water Flow Path
IN Inflow
OU Outflow
OA Outflow-artificial*
OP Outflow-perennial
OI Outflow-intermittent
TH Throughflow
TA Throughflow-artificial*
TI Throughflow-intermittent*
TN Throughflow-entrenched
BI Bidirectional-nontidal
IS Isolated
MI Microtidal
ME Mesotidal
MC Macrotidal
*Note: OA and TA are human-caused by ditches; TI is to be used along intermittent streams.
Estuarine Hydrologic Circulation Type
SW Salt-wedge/river-dominated type
PM Partially mixed type
HO Homogeneous/high energy type
Other Modifiers (apply at end of code)
ch Channelized or Dredged
dv Diverted
ed freshwater stream flowing directly into an estuary
fv Floating vegetation (on the surface)
lv Leveed
md freshwater stream flowing directly into marine waters
sv Submerged vegetation
57
Appendix B. Study findings for individual subbasins. Subbasins are listed alphabetically.
A series of tables of four tables are given for each subbasin: 1) wetland acreage summary by
NWI types, 2) wetland acreage summary by LLWW types, 3) preliminary assessment of wetland
functions, and 4) natural habitat integrity indices.
58
Subbasin: Berry’s Creek above Paterson Avenue
Table 1. Wetlands classified by NWI types for the Berry’s Creek above Paterson Avenue
subbasin.
NWI Wetland Type Acreage
Estuarine Wetlands
Emergent 78.03
Emergent/Scrub-Shrub 3.15
(subtotal Emergent) 81.18
Scrub-Shrub 1.63
Unconsolidated Shore 0.97
--------------------------------------------- - ---------
Estuarine Subtotal 83.78
Palustrine Wetlands
Emergent 182.45
Emergent/Scrub-Shrub 8.66
(subtotal Emergent) 191.11
Forested, Broad-leaved Deciduous 102.35
Scrub-Shrub, Deciduous 13.14
Scrub-Shrub/Emergent 4.73
Scrub-Shrub/Forested 63.87
(subtotal Scrub-Shrub) 81.74
Unconsolidated Bottom 4.33
--------------------------------------------- ------------
Palustrine Subtotal 379.53
Riverine Wetlands 3.40
GRAND TOTAL (ALL WETLANDS) 466.71
59
Table 2. Wetlands in the Berry’s Creek above Paterson Avenue subbasin classified by LLWW
types.
Landscape Number
Position Landform Water Flow of Wetlands* Acreage
Estuarine (ES) Basin Bidirectional-tidal (BT) -- 102.63
Lotic River
(LR) Floodplain (FP) Throughflow (TH) 2 2.96
Lotic Stream
(LS) Basin (BA) Bidirectional-tidal (BT) 4 126.69
Throughflow (TH) 4 20.83
(subtotal) (8) (147.52)
Flat (FL) Bidirectional-tidal (BT) 4 35.51
Throughflow (TH) 2 13.27
(subtotal) (6) (48.8)
Subtotal Lotic Stream 14 196.30
Terrene (TE)
Basin (BA) Isolated (IS) 6 14.44
Outflow (OU) 5 126.43
(subtotal) (11) (140.87)
Flat (FL) Isolated (IS) 3 1.91
Outflow (OU) 2 1.46
(subtotal) (5) (3.37)
Slope (SL) Outflow (OU) 1 12.84
Subtotal Terrene 17 157.08
TOTAL LLWW Types* 33+ 458.97
*Does not include 4 ponds that totaled 4.33 acres. Number of estuarine wetlands not determined.
Note: Subtotals may be slightly different than the sum of acreages in database due to computer
round-off procedures.
60
Table 3. Predicted wetland functions for the Berry’s Creek above Paterson Avenue subbasin.
Function Level Acreage
Surface Water Detention High 255.20
Moderate 193.47
Total 448.67
Streamflow Maintenance High 5.85
Moderate --
Total 5.85
Nutrient Transformation High 393.01
Moderate 65.00
Total 458.01
Sediment and Other Particulate Retention High 421.62
Moderate 25.47
Total 447.09
Coastal Storm Surge Detention High 264.83
Shoreline Stabilization High 294.18
Moderate --
Total 294.18
Fish and Shellfish Habitat High 17.93
Moderate 168.99
Shading 28.84
Total 215.76
Waterfowl and Waterbird Habitat High 30.42
Moderate 186.40
Wood Duck 29.04
Total 245.86
Other Wildlife Habitat High 389.19 (large complexes)
High 26.61 (small diverse wetlands)
Moderate 42.66
Total 458.46
Conservation of Biodiversity 100acre+ complexes 164.00
Meadowlands 265.37
Headwater wetlands 2.96
Total 432.33
61
Table 4. Remotely-sensed indices of “natural habitat integrity” for the Berry’s Creek above
Paterson Avenue subbasin.
Index Score
Natural Cover Index 0.16
River/Stream Corridor Integrity Index 0.40
Wetland Buffer Integrity Index 0.12
Pond/Lake Buffer Integrity Index 0.16
Wetland Extent Index 0.31
Standing Waterbody Extent Index 1.00
Dammed Stream Flowage Index 0.00
Channelized Stream Length Index 1.00
Wetland Disturbance Index 0.61
Habitat Fragmentation by Road Index 0.61
Composite Index 0.06
62
Subbasin: Berry’s Creek below Paterson Avenue
Table 1. Wetlands classified by NWI types for the Berry’s Creek below Paterson Avenue
subbasin.
NWI Wetland Type Acreage
Estuarine Wetlands
Emergent 904.13
Emergent/Scrub-Shrub 4.13
Unconsolidated Shore 1.07
-------------------------------------------- --------
Estuarine Subtotal 909.33
Palustrine Wetlands
Emergent 2.87
Emergent/Scrub-Shrub 5.85
Forested, Broad-leaved Deciduous 1.85
Scrub-Shrub/Forested 4.69
Unconsolidated Bottom 26.84
--------------------------------------------- ------------
Palustrine Subtotal 42.10
Riverine Wetlands 0.49
GRAND TOTAL (ALL WETLANDS) 951.92
63
Table 2. Wetlands in the Berry’s Creek below Paterson Avenue subbasin classified by LLWW
types.
Landscape Number
Position Landform Water Flow of Wetlands* Acreage
Estuarine
(ES) Fringe Bidirectional-tidal (BT) -- 18.58
Basin Bidirectional-tidal (BT) -- 904.33
(Subtotal Estuarine) 922.91
Terrene (TE)
Basin (BA) Isolated (IS) 1 1.66
TOTAL LLWW Types* 1+ 924.57
*Does not include 11 ponds that totaled 26.83 acres. Number of estuarine wetlands not
determined.
Note: Subtotals may be slightly different than the sum of acreages in the database due to
computer round-off procedures.
64
Table 3. Predicted wetland functions for the Berry’s Creek below Paterson Avenue subbasin.
Click on maps to view potential wetlands of significance for each function.
Function Level Acreage
Surface Water Detention High 943.97
Moderate 7.47
Total 951.41
Streamflow Maintenance High --
Moderate --
Total --
Nutrient Transformation High 919.07
Moderate 4.43
Total 923.50
Sediment and Other Particulate Retention High 942.90
Moderate 8.52
Total 951.42
Coastal Storm Surge Detention High 922.91
Shoreline Stabilization High 921.84
Moderate 1.66
Total 923.50
Fish and Shellfish Habitat High 7.63
Moderate 903.45
Shading --
Total 911.08
Waterfowl and Waterbird Habitat High 7.63
Moderate 908.04
Wood Duck 4.41
Total 920.08
Other Wildlife Habitat High 873.20
Moderate 50.30
Total 923.50
Conservation of Biodiversity Meadowlands 872.77
65
Table 4. Remotely-sensed indices of “natural habitat integrity” for the Berry’s Creek below
Paterson Avenue subbasin.
Index Score
Natural Cover Index 0.31
River/Stream Corridor Integrity Index 0.00
Wetland Buffer Integrity Index 0.14
Pond/Lake Buffer Integrity Index 0.10
Wetland Extent Index 0.35
Standing Waterbody Extent Index 1.00
Dammed Stream Flowage Index 0.00
Channelized Stream Length Index 0.00
Wetland Disturbance Index 0.87
Habitat Fragmentation by Road Index 0.72
Composite Index 0.15
66
Subbasin: Coles Brook/Van Saun Mill Brook
Table 1. Wetlands classified by NWI types for the Coles Brook/Van Saun Mill Brook subbasin.
NWI Wetland Type Acreage
Palustrine Wetlands
Emergent 2.10
Emergent/Scrub-Shrub 4.67
Forested, Broad-leaved Deciduous 109.42
Unconsolidated Bottom 7.55
--------------------------------------------- ------------
Palustrine Subtotal 123.74
Riverine Wetlands 3.73
GRAND TOTAL (ALL WETLANDS) 127.47
67
Table 2. Wetlands in the Coles Brook/Van Saun Mill Brook subbasin classified by LLWW
types.
Landscape Number
Position Landform Water Flow of Wetlands Acreage
Lotic River
(LR)
Floodplain (FP) Throughflow (TH) 1 2.15
Fringe (FR) Bidirectional-tidal (BT) 2 1.65
(Subtotal Lotic River) 3 3.80
Lotic Stream
(LS)
Basin (BA) Throughflow (TH) 4 30.84
Flat (FL) Throughflow (TH) 11 61.75
(Subtotal Lotic Stream) 15 92.59
Terrene (TE)
Basin (BA) Isolated (IS) 1 0.53
Outflow (OU) 1 7.83
(subtotal) (2) (8.36)
Flat (FL) Isolated (IS) 3 2.99
Outflow (OU) 2 6.91
(subtotal) (5) (9.90)
Slope (SL) Isolated (IS) 1 1.55
(Subtotal Terrene) 8 19.81
TOTAL LLWW Types* 26 116.20
*Does not include 4 ponds that totaled 7.55 acres.
Note: Subtotals may be slightly different than the sum of acreages in the database due to
computer round-off procedures.
68
Table 3. Predicted wetland functions for the Coles Brook/Van Saun Mill Brook subbasin.
Function Level Acreage
Surface Water Detention High 38.64
Moderate 85.09
Total 123.73
Streamflow Maintenance High 89.50
Moderate 27.21
Total 116.71
Nutrient Transformation High 40.84
Moderate 75.34
Total 116.18
Sediment and Other Particulate Retention High 90.49
Moderate 21.80
Total 112.29
Coastal Storm Surge Detention High 1.65
Shoreline Stabilization High 96.39
Moderate --
Total 96.39
Fish and Shellfish Habitat High 1.65
Moderate 7.55
Shading 58.90
Total 68.10
Waterfowl and Waterbird Habitat High 1.65
Moderate 7.55
Wood Duck 9.60
Total 18.81
Other Wildlife Habitat High 59.29
Moderate 56.89
Total 116.19
Conservation of Biodiversity Headwater wetlands 88.12
Tidal fresh wetlands 1.65
Total 89.77
69
Table 4. Remotely-sensed indices of “natural habitat integrity” for the Coles Brook/Van Saun
Mill Brook subbasin.
Index Score
Natural Cover Index 0.08
River/Stream Corridor Integrity Index 0.18
Wetland Buffer Integrity Index 0.11
Pond/Lake Buffer Integrity Index 0.15
Wetland Extent Index 0.83
Standing Waterbody Extent Index 1.00
Dammed Stream Flowage Index 0.00
Channelized Stream Length Index 0.13
Wetland Disturbance Index 0.10
Habitat Fragmentation by Road Index 0.58
Composite Index 0.18
71
Subbasin: De Forest Lake
Table 1. Wetlands classified by NWI types for the De Forest Lake subbasin.
NWI Wetland Type Acreage
Palustrine Wetlands
Emergent 56.92
Emergent/Scrub-Shrub 10.92
(subtotal Emergent) 67.84
Forested, Broad-leaved Deciduous 330.14
Forested, Needle-leaved Evergreen 2.59
Forested/Scrub-Shrub 7.98
Forested/Emergent 6.68
(subtotal Forested) 347.39
Scrub-Shrub, Deciduous 20.78
Scrub-Shrub/Emergent 1.99
(subtotal Scrub-Shrub) 22.77
Unconsolidated Bottom 66.84
Unconsolidated Shore 1.12
--------------------------------------------- ------------
Palustrine Subtotal 505.96
Riverine Wetlands 6.83
GRAND TOTAL (ALL WETLANDS) 512.79
72
Table 2 Wetlands in the De Forest Lake subbasin classified by LLWW types.
Landscape Number
Position Landform Water Flow of Wetlands Acreage
Lentic (LE)
Basin (BA) Bidirectional (BI) 7 10.45
Throughflow (TH) 3 23.83
(subtotal) 10 34.28
Flat (FL) Bidirectional (BI) 4 6.50
Isolated (IS) 1 3.27
(subtotal) 5 9.77
Fringe (FR) Bidirectional (BI) 1 1.08
(Subtotal Lentic) 16 45.13
Lotic Stream
(LS)
Basin (BA) Throughflow (TH) 28 264.09
Flat (FL) Throughflow (TH) 7 15.69
Fringe (FR) Throughflow (TH) 1 0.19
(Subtotal Lotic Stream) 36 279.97
Terrene (TE)
Basin (BA) Isolated (IS) 34 35.01
Outflow (OU) 9 63.67
(subtotal) 43 98.68
Flat (FL) Isolated (IS) 3 2.95
Outflow (OU) 5 12.38
(subtotal) 8 15.33
(Subtotal Terrene) 51 114.01
TOTAL LLWW Types* 103 439.11
*Does not include 73 ponds that totaled 50.80 acres.
Note: Subtotals may be slightly different than the sum of acreages shown due to computer round-off
procedures.
73
Table 3. Predicted wetland functions for the De Forest Lake subbasin.
Function Level Acreage
Surface Water Detention High 325.23
Moderate 164.35
Total 489.58
Streamflow Maintenance High 142.61
Moderate 273.60
Total 416.21
Nutrient Transformation High 397.21
Moderate 40.79
Total 438.00
Sediment and Other Particulate Retention High 322.38
Moderate 151.88
Total 474.26
Shoreline Stabilization High 334.38
Moderate 13.10
Total 347.75
Fish and Shellfish Habitat High 2.18
Moderate 51.91
Shading 241.66
Total 295.75
Waterfowl and Waterbird Habitat High 17.96
Moderate 59.73
Wood Duck 223.97
Total 301.66
Other Wildlife Habitat High 207.33 (large complexes)
High 118.52 (small diverse wetlands)
Moderate 112.16
Total 438.01
Conservation of Biodiversity 100acre+ complexes 171.50
Headwater wetlands 143.88
Lentic basins/fringes 11.29
Possible vernal pool 0.39
Total 327.06
74
Table 4. Remotely-sensed indices of “natural habitat integrity” for the DeForest Lake subbasin.
Index Score
Natural Cover Index 0.39
River/Stream Corridor Integrity Index 0.44
Wetland Buffer Integrity Index 0.51
Pond/Lake Buffer Integrity Index 0.56
Wetland Extent Index 0.39
Standing Waterbody Extent Index 1.00
Dammed Stream Flowage Index 0.30
Channelized Stream Length Index 0.29
Wetland Disturbance Index 0.66
Habitat Fragmentation by Road Index 0.34
Composite Index 0.32
75
Subbasin: Dwars Kill
Table 1. Wetlands classified by NWI types for the Dwars Kill subbasin.
NWI Wetland Type Acreage
Palustrine Wetlands
Emergent 3.19
Forested, Broad-leaved Deciduous 374.40
Forested/Scrub-Shrub 2.36
Forested/Emergent 5.23
(subtotal Forested) 381.99
Scrub-Shrub, Deciduous 6.16
Scrub-Shrub/Emergent 8.48
Scrub-Shrub/Forested 3.13
(subtotal Scrub-Shrub) 17.77
Unconsolidated Bottom 5.08
--------------------------------------------- ------------
Palustrine Subtotal 408.03
Riverine Wetlands 6.94
GRAND TOTAL (ALL WETLANDS) 414.97
76
Table 2. Wetlands in the Dwars Kill subbasin classified by LLWW types.
Landscape Number
Position Landform Water Flow of Wetlands Acreage
Lentic (LE)
Basin (BA) Throughflow (TH) 6 31.46
Flat (FL) Bidirectional (BI) 4 8.92
Throughflow (TH) 6 44.41
(subtotal) 10 53.33
(Subtotal Lentic) 16 84.79
Lotic Stream
(LS)
Basin (BA) Throughflow (TH) 10 135.25
Flat (FL) Throughflow (TH) 12 105.58
(Subtotal Lotic Stream) 22 240.83
Terrene (TE)
Basin (BA) Isolated (IS) 5 12.60
Outflow (OU) 2 0.70
(subtotal) 7 13.30
Flat (FL) Isolated (IS) 6 36.33
Outflow Intermittent (OI)
Outflow (OU) 6 27.42
(subtotal) 12 63.75
Slope (SL) Isolated (IS) 1 0.28
(Subtotal Terrene) 19 77.33
TOTAL LLWW Types* 57 402.83
*Does not include 5 ponds that totaled 5.07 acres.
Note: Subtotals may be slightly different than the sum of acreages shown due to computer round-off
procedures.
77
Table 3. Predicted wetland functions for the Dwars Kill subbasin.
Function Level Acreage
Surface Water Detention High 224.47
Moderate 168.14
Total 392.61
Streamflow Maintenance High 33.67
Moderate 233.01
Total 266.68
Nutrient Transformation High 180.02
Moderate 222.93
Total 402.95
Sediment and Other Particulate Retention High 263.75
Moderate 80.25
Total 344.00
Shoreline Stabilization High 325.84
Moderate --
Total 325.84
Fish and Shellfish Habitat High --
Moderate 5.08
Shading 225.13
Total 230.21
Waterfowl and Waterbird Habitat High 0.13
Moderate 5.08
Wood Duck 133.32
Total 138.53
Other Wildlife Habitat High 306.09 (large complexes)
High 23.04 (small diverse wetlands)
Moderate 73.81
Total 402.94
Conservation of Biodiversity 100 acre+ wetlands 346.68
Headwater wetlands 26.83
Total 373.51
78
Table 4. Remotely-sensed indices of “natural habitat integrity” for the Dwars Kill subbasin.
Index Score
Natural Cover Index 0.44
River/Stream Corridor Integrity Index 0.64
Wetland Buffer Integrity Index 0.56
Pond/Lake Buffer Integrity Index 0.68
Wetland Extent Index 0.70
Standing Waterbody Extent Index 1.00
Dammed Stream Flowage Index 0.00
Channelized Stream Length Index 0.09
Wetland Disturbance Index 0.07
Habitat Fragmentation by Road Index 0.26
Composite Index 0.53
79
Subbasin: Hackensack River - Amtrak Bridge to Route 3
Table 1. Wetlands classified by NWI types for the Hackensack River - Amtrak Bridge to Rt. 3
subbasin.
NWI Wetland Type Acreage
Estuarine Wetlands
Emergent 655.62
Unconsolidated Shore 775.72
--------------------------------------------- -----------
Estuarine Subtotal 1431.33
Palustrine Wetlands
Emergent 21.40
Forested, Broad-leaved Deciduous 2.00
Scrub-Shrub, Deciduous 7.84
Unconsolidated Bottom 13.21
Unconsolidated Shore 3.46
--------------------------------------------- ------------
Palustrine Subtotal 47.91
Riverine Wetlands 2.39
GRAND TOTAL (ALL WETLANDS) 1,481.63
80
Table 2. Wetlands in the Hackensack River - Amtrak Bridge to Rt. 3 subbasin classified by
LLWW types.
Landscape Number
Position Landform Water Flow of Wetlands* Acreage
Estuarine (ES) Fringe Bidirectional-tidal (BT) -- 962.33
Basin Bidirectional-tidal (BT) -- 484.36
Island Bidirectinal-tidal (BT) -- 0.75
(Subtotal Estuarine) 1447.44
Lotic Stream
(LS)
Flat (FL) Throughflow (TH) 1 1.63
(Subtotal Lotic Stream) 1.63
Terrene (TE)
Basin (BA) Isolated (IS) 3 2.36
Outflow (OU) 4 8.01
(subtotal) 7 10.37
Flat (FL) Outflow (OU) 1 3.14
(Subtotal Terrene) 8 13.51
TOTAL LLWW Types* 9+ 1462.58
*Does not include 14 ponds that totaled 16.67 acres. Number of estuarine wetlands not
determined.
Note: Subtotals may be slightly different than the sum of acreages shown due to computer round-off
procedures.
81
Table 3. Predicted wetland functions for the Hackensack River - Amtrak Bridge to Rt. 3
subbasin.
Function Level Acreage
Surface Water Detention High 1453.45
Moderate 22.34
Total 1475.79
Streamflow Maintenance High 1.63
Moderate 3.69
Total 5.32
Nutrient Transformation High 682.09
Moderate 4.77
Total 686.86
Sediment and Other Particulate Retention High 682.30
Moderate 793.80
Total 1476.10
Coastal Storm Surge Detention High 1447.44
Shoreline Stabilization High 673.36
Moderate --
Total 673.36
Fish and Shellfish Habitat High 1030.90
Moderate 418.69
Shading 1.63
Total 1451.22
Waterfowl and Waterbird Habitat High 1023.32
Moderate 377.28
Wood Duck 0.39
Total 1400.99
Other Wildlife Habitat High 622.59 (large complexes)
High 3.23 (small diverse wetlands)
Moderate 61.04
Total 686.86
Conservation of Biodiversity Meadowlands 1436.29
Headwater wetlands 1.63
Tidal fresh wetlands 0.39
Total 1438.31
82
Table 4. Remotely-sensed indices of “natural habitat integrity” for the Hackensack River -
Amtrak Bridge to Rt. 3 subbasin.
Index Score
Natural Cover Index 0.45
River/Stream Corridor Integrity Index 0.03
Wetland Buffer Integrity Index 0.04
Pond/Lake Buffer Integrity Index 0.22
Wetland Extent Index 0.16
Standing Waterbody Extent Index 1.00
Dammed Stream Flowage Index 0.00
Channelized Stream Length Index 1.00
Wetland Disturbance Index 0.55
Habitat Fragmentation by Road Index 0.56
Composite Index 0.15
83
Subbasin: Hackensack River above Tappan Bridge
Table 1. Wetlands classified by NWI types for the Hackensack River above Tappan Bridge
subbasin.
NWI Wetland Type Acreage
Palustrine Wetlands
Emergent 6.68
Emergent/Scrub-Shrub 4.38
(subtotal Emergent) 11.06
Forested, Broad-leaved Deciduous 345.59
Forested/Scrub-Shrub 12.63
(subtotal Forested) 358.22
Scrub-Shrub, Deciduous 0.87
Unconsolidated Bottom 27.27
--------------------------------------------- ------------
Palustrine Subtotal 397.42
Riverine Wetlands 4.20
GRAND TOTAL (ALL WETLANDS) 401.62
84
Table 2. Wetlands in the Hackensack River above Tappan Bridge subbasin classified by LLWW
types.
Landscape Number
Position Landform Water Flow of Wetlands Acreage
Lentic (LE)
Basin (BA) Bidirectional (BI) 3 2.09
Throughflow (TH) 2 3.31
(subtotal)
Fringe (FR) Bidirectional (BI) 1 0.38
(Subtotal Lentic) 6 5.78
Lotic River
(LR)
Floodplain (FP) Throughflow (TH) 8 148.15
(Subtotal Lotic River) 148.15
Lotic Stream
(LS)
Basin (BA) Throughflow (TH) 19 107.37
Flat (FL) Throughflow (TH) 15 37.83
(Subtotal Lotic Stream) 34 145.20
Terrene (TE)
Basin (BA) Isolated (IS) 12 10.73
Outflow (OU) 6 19.78
(subtotal) 18 30.51
Flat (FL) Isolated (IS) 4 3.54
Outflow (OU) 3 6.40
(subtotal) 7 9.94
Slope (SL) Isolated (IS) 1 13.80
Outflow (OU) 5 16.76
(subtotal) 6 30.56
(Subtotal Terrene) 31 71.01
TOTAL LLWW Types* 79 370.14
*Does not include 33 ponds that totaled 27.26 acres.
Note: Subtotals may be slightly different than the sum of acreages shown due to computer round-off
procedures.
85
Table 3. Predicted wetland functions for the Hackensack River above Tappan Bridge subbasin.
Function Level Acreage
Surface Water Detention High 277.05
Moderate 117.13
Total 394.19
Streamflow Maintenance High 155.33
Moderate 195.15
Total 350.48
Nutrient Transformation H