Environmental Assessment of the Lower
Cape Fear River System, 2005
By
Michael A. Mallin, Matthew R. McIver and James F. Merritt
September 2006
CMS Report No. 06-02
Center for Marine Science
University of North Carolina Wilmington
Wilmington, N.C. 28409
Executive Summary
Multiparameter water sampling for the Lower Cape Fear River Program (LCFRP) has
been ongoing since June 1995. Scientists from the University of North Carolina
Wilmington (UNCW) perform the sampling effort. The LCFRP currently encompasses
36 water sampling stations throughout the Cape Fear, Black, and Northeast Cape Fear
River watersheds. The LCFRP sampling program includes physical, chemical, and
biological water quality measurements and analyses of the benthic and epibenthic
macroinvertebrate communities, and has in the past included assessment of the fish
communities. Principal conclusions of the UNCW researchers conducting these
analyses are presented below, with emphasis on the period January - December 2005.
The opinions expressed are those of UNCW scientists and do not necessarily reflect
viewpoints of individual contributors to the Lower Cape Fear River Program.
The mainstem lower Cape Fear River is characterized by reasonably turbid water
containing moderate to high levels of inorganic nutrients. It is fed by two large
blackwater rivers (the Black and Northeast Cape Fear Rivers) that have low levels of
turbidity, but highly colored water with less inorganic nutrient content than the
mainstem. While nutrients are reasonably high in the river channels, algal blooms are
rare because light is attenuated by water color or turbidity, and flushing is high. Periodic
algal blooms are seen in the tributary stream stations, some of which are impacted by
point source discharges. Below some point sources, nutrient loading can be high and
fecal coliform contamination occurs. Other stream stations drain blackwater swamps or
agricultural areas, some of which periodically show elevated pollutant loads or effects.
Annual mean salinity for 2005 was higher than the nine-year average for 1996-2004 at
all stations. River discharge for 2005 continued a three-year decrease from the high
discharge period of 2003. This influenced salinity and also appeared to lead to a
reduction in concentration of certain nutrients and other parameters (suspended solids
and turbidity) in the main channel and estuary stations.
Average annual dissolved oxygen (DO) levels at the river channel stations for 2005
were slightly higher than the average for 1996-2004, possibly due to the lack of major
hurricane activity in the watershed last year. Dissolved oxygen levels were lowest
during the summer, often falling below the state standard of 5.0 mg/L at several river
and upper estuary stations. There is a dissolved oxygen sag in the main river channel
that begins at Station DP below a paper mill discharge and near the Black River input,
and persists into the mesohaline portion of the estuary. Mean oxygen levels were
highest at the upper river stations NC11 and AC and in the middle to lower estuary at
station M23. Lowest mainstem mean 2005 DO levels occurred at the lower river and
upper estuary stations NAV and HB (7.1 mg/L). As the water reaches the lower estuary
higher algal productivity, mixing and ocean dilution help alleviate oxygen problems.
The Northeast Cape Fear and Black Rivers generally have lower DO levels than the
mainstem Cape Fear River. These rivers are classified as blackwater systems because
of their tea colored water. The Northeast Cape Fear River in general seems to be more
oxygen stressed than the Black River; in 2005 Station NCF117 had DO concentrations
below 4.0 mg/L 33% of the time sampled, while during that same period Station B210
had DO below 4.0 mg/L 0% of the occasions sampled. Several stream stations were
severely stressed in terms of low dissolved oxygen during the year 2005. Station ANC
had DO levels below 4.0 mg/L 50% of the occasions sampled, NC403 33%, GS 67%,
BCRR 42% and SR 58%. Smith Creek had DO levels below the tidal water standard of
5.0 mg/L 42% of the time.
Annual mean turbidity levels for 2005 were considerably lower than the long-term
average, probably a result of low rainfall. Highest mean turbidities were at the upper
river sites N11, AC and DP (17-19 NTU) with turbidities gradually decreasing
downstream through the estuary. Turbidity was lower in the blackwater tributaries
(Northeast Cape Fear River and Black River) than in the mainstem river.
Regarding stream stations, chronic or periodic high nutrient levels were found at a
number of sites, including BC117, 6RC, GS, GCO,NC403, PB and SAR. Algal blooms
were rare in 2005, primarily occurring at Station PB, a nutrient-impacted stream site
downstream of a point source, and Stations GS and BCRR. Several stream stations,
particularly BCRR, BC117, PB, GS, and ANC showed high fecal coliform counts on a
number of occasions. Biochemical oxygen demand (BOD) concentrations in several
Northeast Cape Fear River watershed stream stations were considerably higher than
BOD concentrations previously found in the neighboring Black River watershed stream
stations. Water column metals concentrations were not problematic during 2005.
This report includes an in-depth look at each subbasin, comparing the results of the
North Carolina Division of Water Quality's 2005 Basinwide Management Plan use
support ratings with the UNCW-Aquatic Ecology Laboratory’s (AEL) assessments of the
2005 sampling year. The UNCW-AEL utilized ratings that consider a water body to be
of poor quality if the water quality standard for a given parameter is in violation > 25% of
the time, of fair quality if the standard is in violation between 11 and 25% of the time,
and good quality if the standard is violated no more than 10% of the time. UNCW also
considerers nutrient loading in water quality assessments, based on published
experimental and field scientific findings.
For the 2005 period UNCW rated all stations as good in terms of chlorophyll a, except
for Station PB, rated fair. For turbidity 100% of the sites were rated good. However,
22% of the stations had either fair or poor water quality in terms of fecal coliform
bacterial contamination. Using the 5.0 mg/L DO standard for the Piedmont river
stations, and the 4.0 mg/L “swamp water” DO standard for the stream stations and
blackwater river stations, 41% of the sites were rated poor or fair for dissolved oxygen.
In addition, UNCW considered 60% of the stream stations to be negatively impacted by
excessive nitrate and 10% of the stream stations negatively affected by excessive total
phosphorus concentrations.
Table of Contents
1.0 Introduction...........................................................................………...............…........1
1.1 Site Description................................................……….....................…..........2
2.0 Physical, Chemical, and Biological Characteristics of the Lower Cape Fear River
and Estuary………………………………………………..…………………….....….. ….8
Physical Parameters..…......................………..........................................……....10
Chemical Parameters…....……..……….........................................................…..13
Biological Parameters.......……….....……......................................................…..17
3.0 Water Quality by Sub-basin in the Lower Cape Fear River System………………..54
1
1.0 Introduction
Michael A. Mallin
Center for Marine Science
University of North Carolina Wilmington
The Lower Cape Fear River Program is a unique science and education program that
has a mission to develop an understanding of processes that control and influence the
ecology of the Cape Fear River, and to provide a mechanism for information exchange
and public education. This Program provides a forum for dialogue among the various
Cape Fear River user groups and encourages interaction among them. Overall policy is
set by an Advisory Board consisting of representatives from citizen’s groups, local
government, industries, academia, the business community, and regulatory agencies.
This report represents the scientific conclusions of the UNCW researchers participating
in this Program and does not necessarily reflect opinions of all other Program
participants. This report focuses on the period January through December 2005.
The scientific basis of the Program consists of the implementation of an ongoing
comprehensive physical, chemical, and biological monitoring program. Another part of
the mission is to develop and maintain a data base on the Cape Fear basin and make
use of this data to develop management plans. Presently the Program has amassed a
ten-year (1995-2004) data base freely available to the public. Using this monitoring
data as a framework the Program goals also include focused scientific projects and
investigation of pollution episodes. The scientific aspects of the Program are carried out
by investigators from the University of North Carolina Wilmington Center for Marine
Science. The monitoring program was developed by the Lower Cape Fear River
Program Technical Committee, which consists of representatives from UNCW, the
North Carolina Division of Water Quality, The NC Division of Marine Fisheries, the US
Army Corps of Engineers, technical representatives from streamside industries, the City
of Wilmington Wastewater Treatment Plants, Cape Fear Community College, Cape
Fear River Watch, the North Carolina Cooperative Extension Service, the US
Geological Survey, forestry and agriculture organizations, and others. This integrated
and cooperative program was the first of its kind in North Carolina.
Broad-scale monthly water quality sampling at 16 stations in the estuary and lower river
system began in June 1995 (directed by Dr. Michael Mallin). Sampling was increased
to 34 stations in February of 1996, 35 stations in February 1998, and 36 stations in
2005. The Lower Cape Fear River Program added another component concerned with
studying the benthic macrofauna of the system in 1996. This component is directed by
Dr. Martin Posey of the UNCW Biology Department and includes the benefit of
additional data collected by the Benthic Ecology Laboratory under Sea Grant and NSF
sponsored projects in the Cape Fear Estuary. The third major biotic component (added
in January 1996) was an extensive fisheries program directed by Dr. Mary Moser of the
UNCW Center for Marine Science Research, with subsequent (1999) overseeing by Mr.
Michael Williams and Dr. Thomas Lankford of UNCW-CMS. This program involved
2
cooperative sampling with the North Carolina Division of Marine Fisheries and the North
Carolina Wildlife Resources Commission. The fisheries program ended in December
1999, but was renewed with additional funds from the Z. Smith Reynolds Foundation
from spring – winter 2000, and has been operational periodically for special projects
since that period. The regular sampling that was conducted by UNCW biologists was
assumed by the North Carolina Division of Marine Fisheries.
1.1. Site Description
The mainstem of the Cape Fear River is formed by the merging of the Haw and the
Deep Rivers in Chatham County in the North Carolina Piedmont. However, its drainage
basin reaches as far upstream as the Greensboro area (Fig. 1.1). The mainstem of the
river has been altered by the construction of several dams and water control structures.
In the coastal plain, the river is joined by two major tributaries, the Black and the
Northeast Cape Fear Rivers (Fig. 1.1). These 5th order blackwater streams drain
extensive riverine swamp forests and add organic color to the mainstem. The
watershed (about 9,149 square miles) is the most heavily industrialized in North
Carolina with 244 permitted wastewater discharges and (as of 2000) over 1.83 million
people residing in the basin (NCDENR 2005). Approximately 24% of the land use in the
watershed is devoted to agriculture and livestock production (NCDENR 2005), with
livestock production dominated by swine and poultry operations. Thus, the watershed
receives considerable point and non-point source loading of pollutants.
Water quality is monitored by boat at ten stations in the Cape Fear Estuary (from
Navassa to Southport) and one station in the Northeast Cape Fear Estuary (Table 1.1;
Fig. 1.1). Riverine stations sampled by boat include NC11, AC, DP, IC, and BBT (Table
1.1; Fig. 1.1). NC11 is located upstream of any major point source discharges in the
lower river and estuary system, and is considered to be representative of water quality
entering the lower system. BBT is located on the Black River between Thoroughfare
and the mainstem Cape Fear, and is influenced by both rivers. We consider B210 and
NCF117 to represent water quality entering the lower Black and Northeast Cape Fear
Rivers, respectively. Data has also been collected at stream and river stations
throughout the Cape Fear, Northeast Cape Fear, and Black River watersheds (Table
1.1; Fig. 1.1). Data collection at a station in the Atlantic Intracoastal Waterway was
initiated in February 1998 to obtain water quality information near the Southport
Wastewater Treatment Plant discharge.
The LCFRP has a website that contains maps and an extensive amount of past water
quality, benthos, and fisheries data gathered by the Program available at:
www.uncwil.edu/cmsr/aquaticecology/lcfrp/
This report contains three sections assessing LCFRP data. Section 2 presents an
overview of physical, chemical, and biological water quality data from the 36 individual
stations, and provides tables of raw data as well as figures showing spatial or temporal
trends. In Section 3 we analyze our data by sub-basin, compare our results with DWQ's
2005 Basinwide Plan, and make water quality ratings for dissolved oxygen, turbidity,
3
chlorophyll a, metals, and fecal coliform bacterial abundance. We also utilize other
relevant parameters such as nutrient concentrations to aid in these assessments. This
section is designed so that residents of a particular sub-basin can see what the water
quality is like in his or her area based on LCFRP data collections.
1.2. References Cited
NCDENR. 2005. Cape Fear River Basinwide Water Quality Plan. North Carolina
Department of Environment and Natural Resources, Division of Water
Quality/Planning, Raleigh, NC, 27699-1617.
4
Table 1.1. Description of sampling locations in the Cape Fear Watershed, 2005,
including UNCW designation and NCDWQ station designation number.
________________________________________________________________
UNCW St. DWQ No.
Location
________________________________________________________________
High order river and estuary stations
NC11
GPS
B8360000
At NC 11 bridge on Cape Fear River (CFR)
N 34.39663
W 78.26785
LVC2
GPS
B8441000
on Livingston Creek near Acme
N 34.33530
W 78.2011
AC
GPS
B8450000
5 km downstream from International Paper on CFR
N 34.35547
W 78.17942
DP
GPS
B8460000
At Dupont Intake above Black River
N 34.33595
W 78.05337
IC
GPS
B9030000
Cluster of dischargers upstream of Indian Cr. on CFR
N 34.30207
W 78.01372
B210
GPS
B9000000
Black River at Highway 210 bridge
N 34.43138
W 78.14462
BBT
GPS
none
Black River between Thoroughfare and Cape Fear River
N 34.35092
W 78.04857
NCF117
GPS
B9580000
Northeast Cape Fear River at Highway 117, Castle Hayne
N 34.36342
W 77.89678
NCF6
GPS
B9670000
Northeast Cape Fear River near GE dock
N 34.31710
W 77.95383
NAV
GPS
B9050000
Railroad bridge over Cape Fear River at Navassa
N 34.25943
W 77.98767
HB
GPS
B9050100
Cape Fear River at Horseshoe Bend
N 34.24372
W 77.96980
BRR
GPS
B9790000
Brunswick River near new boat ramp in Belville
N 34.22138
W 77.97868
5
M61
GPS
B9750000
Channel Marker 61, downtown at N.C. State Port
N 34.19377
W 77.95725
M54
GPS
B7950000
Channel Marker 54, 5 km downstream of Wilmington
N 34.13933
W 77.94595
M42
GPS
B9845100
Channel Marker 42 near Keg Island
N 34.09017
W 77.93355
M35
GPS
B9850100
Channel Marker 35 near Olde Brunswick Towne
N 34.03408
W 77.93943
M23
GPS
B9910000
Channel Marker 23 near CP&L intake canal
N 33.94560
W 77.96958
M18
GPS
B9921000
Channel Marker 18 near Southport
N 33.91297
W 78.01697
SPD
B9980000 1000 ft W of Southport WWT plant discharge on ICW
GPS
N 33.91708
W 78.03717
________________________________________________________________
Tributary stations collected from land
________________________________________________________________
SR
GPS
B8470000
South River at US 13, below Dunn runoff
N 35.15600
W 78.64013
GCO
GPS
B8604000
Great Coharie Creek at SR 1214
N 34.91857
W 78.38873
LCO
GPS
B8610001
Little Coharie Creek at SR 1207
N 34.83473
W 78.37087
6RC
GPS
B8740000
Six Runs Creek at SR 1003 (Lisbon Rd.)
N 34.79357
W 78.31192
BRN
GPS
B8340050
Browns Creek at NC 87
N 34.61360
W 78.58462
HAM
GPS
B8340200
Hammonds Creek at SR 1704
N 34.56853
W 78.55147
COL
GPS
B8981000
Colly Creek at NC 53
N 34.46500
W 78.26553
6
ANC
GPS
B9490000
Angola Creek at NC 53
N 34.65705
W 77.73485
NC403
GPS
B9090000
Northeast Cape Fear below Mt. Olive Pickle at NC403
N 35.17838
W 77.98028
PB
GPS
B9130000
Panther Branch below Cates Pickle
N 35.13445
W 78.13630
GS
GPS
B9191000
Goshen Swamp at NC 11
N 35.02923
W 77.85143
SAR
GPS
B9191500
Northeast Cape Fear River near Sarecta
N 34.97970
W 77.86251
LRC
GPS
B9460000
Little Rockfish Creek at NC 11
N 34.72247
W 77.98145
ROC
GPS
B9430000
Rockfish Creek at US 117
N 34.71689
W 77.97961
BCRR
GPS
B9500000
Burgaw Canal at Wright St., above WWTP
N 34.56334
W 77.93481
BC117
GPS
B9520000
Burgaw Canal at US 117, below WWTP
N 34.56391
W 77.92210
SC-CH
GPS
Smith Creek at Castle Hayne Rd.
N 34.25897
W 77.93872
7
Figure 1.1 Map of the Lower Cape Fear River system and the LCFRP sampling stations.
8
2.0 - Physical, Chemical, and Biological Characteristics of the
Lower Cape Fear River and Estuary
Matthew R. McIver and Michael A. Mallin
Center for Marine Science
University of North Carolina Wilmington
2.1 - Introduction
This section of the report includes a discussion of the physical, chemical, and biological
water quality parameters, concentrating on the January-December 2005 Lower Cape Fear
River Program monitoring period. These parameters are interdependent and define the
overall condition of the river. Physical parameters measured during this study included
water temperature, dissolved oxygen, turbidity, salinity, conductivity, pH and light
attenuation. The chemical makeup of the Cape Fear River was investigated by measuring
the magnitude and composition of nitrogen and phosphorus in the water, as well as
concentrations of United States Environmental Protection Agency (US EPA) priority
pollutant metals. Three biological parameters including fecal coliform bacteria, chlorophyll
a and biochemical oxygen demand were examined.
2.2 - Materials and Methods
All samples and field parameters collected for the estuarine stations of the Cape Fear
River (NAV down through M18) were gathered on an ebb tide. This was done so that the
data better represented the river water flowing downstream through the system rather than
the tidal influx of coastal ocean water. Sample collection and analyses were conducted
according to the procedures in the Lower Cape Fear River Program Quality
Assurance/Quality Control (QA/QC) manual, which has been approved by the NC Division
of Water Quality. We note that our previous Livingston Creek station (LVC) has been
discontinued and a new station sampled from the dock of the Wright Chemical Company
near Acme (LVC2) was put into operation in 2005.
Physical Parameters
Water Temperature, pH, Dissolved Oxygen, Turbidity, Salinity, Conductivity
Field parameters were measured at each site using a YSI 6920 (or 6820) multi-parameter
water quality sonde displayed on a YSI 650 MDS. Each parameter is measured with
individual probes on the sonde. At stations sampled by boat (see Table 1.1) physical
parameters were measured at 0.1 m, the middle of the water column, and at the bottom
(up to 12 m). Occasionally, high flow prohibited the sonde from reaching the actual bottom
and measurements were taken as deep as possible. At the terrestrially sampled stations
the physical parameters were measured at a depth of 0.1 m. Our laboratory at the UNCW
CMS is State-certified by the N.C. Division of Water Quality to perform field parameter
measurements.
9
Chemical Parameters
Nutrients
All nutrient analyses were performed at the UNCW Center for Marine Science (CMS) for
samples collected prior to January 1996. A local State-certified analytical laboratory was
contracted to conduct all subsequent analyses except for orthophosphate, which is
performed at CMS. The following methods detail the techniques used by CMS personnel
for orthophosphate analysis.
Orthophosphate (PO4-3)
Water samples were collected ca. 0.2 m below the surface in triplicate in amber 125 mL
Nalgene plastic bottles and placed on ice. In the laboratory 50 mL of each triplicate was
filtered through separate1.0 micron pre-combusted glass fiber filters, which were frozen
and later analyzed for chlorophyll a. The triplicate filtrates were pooled in a glass flask,
mixed thoroughly, and approximately 100 mL was poured into a 125 mL plastic bottle to be
analyzed for orthophosphate. Samples were frozen until analysis.
Orthophosphate analyses were performed in duplicate using an approved US EPA method
for the Bran-Lubbe AutoAnalyzer (Method 365.5). In this technique the orthophosphate in
each sample reacts with ammonium molybdate and anitmony potassium tartrate in an
acidic medium (sulfuric acid) to form an anitmony-phospho-molybdate complex. The
complex is then reacted with ascorbic acid and forms a deep blue color. The intensity of
the color is measured at a wavelength of 880 nm by a colorimeter and displayed on a chart
recorder. Standards and spiked samples were analyzed for quality assurance.
Biological Parameters
Fecal Coliform Bacteria
Fecal coliform bacteria were analyzed at a State-certified laboratory contracted by the
LCFRP. Samples were collected approximately 0.2 m below the surface in sterile plastic
bottles provided by the contract laboratory and placed on ice for no more than six hours
before analysis.
Chlorophyll a
The analytical method used to measure chlorophyll a is described in Welschmeyer (1994)
and US EPA (1997) and was performed by CMS personnel. Chlorophyll a concentrations
were determined directly from the 1.0 micron filters used for filtering samples for
orthophosphate analysis. All filters were wrapped individually in foil, placed in airtight
containers and stored in the freezer. During analysis each filter is immersed in 10 mL of
10
90% acetone for 24 hours, which extracts the chlorophyll a into solution. Additionally,
filters from samples taken at M61, M18, BC117 and BCRR are ground during the
extraction process. Chlorophyll a concentration of each solution is measured on a Turner
10-AU fluorometer. The fluorometer uses an optimal combination of excitation and
emission bandwidth filters which reduces the errors inherent in the acidification technique.
Our laboratory at the CMS is State-certified by the N.C. Division of Water Quality for the
analysis of chlorophyll a.
Biochemical Oxygen Demand (BOD)
Five sites were originally chosen for BOD analysis. One site was located at NC11,
upstream of International Paper, and a second site was at AC, about 3 miles downstream
of International Paper (Fig.1.1). Two sites were located in blackwater rivers (NCF117 and
B210) and one site (BBT) was situated in an area influenced by both the mainstem Cape
Fear River and the Black River. For the sampling period May 2000-April 2004 additional
BOD data were collected at stream stations 6RC, LCO, GCO, BRN, HAM and COL in the
Cape Fear and Black River watersheds. In May 2004 those stations were dropped and
sampling commenced at ANC, SAR, GS, N403, ROC and BC117 in the Northeast Cape
Fear River watershed. The procedure used for BOD analysis was Method 5210 in
Standard Methods (APHA 1995). Samples were analyzed for both 5-day and 20-day
BOD. During the analytical period, samples were kept in airtight bottles and placed in an
incubator at 20o C. All experiments were initiated within 6 hours of sample collection.
Samples were analyzed in duplicate. Dissolved oxygen measurements were made using
a YSI Model 57 meter that was air-calibrated. No adjustments were made for pH since
most samples exhibited pH values within or very close to the desired 6.5-7.5 range.
Several sites have naturally low pH and there was no adjustment for these samples
because it would alter the natural water chemistry and affect true BOD.
2.3 - Results and Discussion
This section includes results from monitoring of the physical, biological, and chemical
parameters at all stations for the time period January-December 2005. Discussion of the
data focuses mainly on the river channel stations, but poor water quality conditions at
stream stations will also be discussed. The contributions of the two large blackwater
tributaries, the Northeast Cape Fear River and the Black River, are represented by
conditions at NCF117 and B210, respectively. The Cape Fear Region did not experience
any significant hurricane activity during this monitoring period (after major hurricanes in
1996, 1998, and 1999). Therefore this report reflects low flow conditions for the Cape Fear
River and Estuary.
Physical Parameters
Water temperature
Water temperatures at all stations ranged from 3.7 to 31.1 oC and individual station annual
averages ranged from 15.1 to 20.0oC (Table 2.1). Highest temperatures occurred during
11
July and August and lowest temperatures during February. Stream stations were
generally cooler than river stations, most likely because of shading and lower nighttime air
temperatures affecting the shallower waters.
Salinity
Salinity at the estuarine stations ranged from 0.1 to 34.7 practical salinity units (psu) and
station annual means ranged from 2.5 to 28.2 psu (Table 2.2). Lowest salinities occurred
in April and highest salinities occurred in September. Two stream stations, NC403 and
PB, had occasional oligohaline conditions due to discharges from pickle production
facilities. Annual mean salinity for 2005 was higher than the nine-year average for 19962004 at all stations (Figure 2.1). River discharge for 2005 continued a three-year decrease
from the high discharge period of 2003 (see USGS data at http://nc.water.usgs.gov). This
influenced salinity, and also appeared to lead to a reduction in concentration of certain
nutrients and other parameters (TSS and turbidity) in the main channel and estuary
stations (see below).
Conductivity
Conductivity at estuarine stations ranged from 0.10 to 52.68 mS/cm and from 0.1 to 4.0
mS/cm at the freshwater stations (Table 2.3). Temporal conductivity patterns followed
those of salinity. Dissolved ionic compounds increase the conductance of water, therefore,
conductance increases and decreases with salinity, often reflecting river flow conditions
due to rainfall. Conductivity may also reveal point source pollution sources, as is seen at
BC117, which is below a municipal wastewater discharge. Stations PB and NC403 are
below an industrial discharge, and often has elevated conductivity.
pH
pH values ranged from 3.2 to 8.2 and station annual medians ranged from 3.8 to 8.0
(Table 2.4). pH was typically lowest upstream due to acidic swamp water inputs and
highest downstream as alkaline seawater mixes with the river water. Low pH values at
COL predominate because of naturally acidic blackwater inputs.
Dissolved Oxygen
Dissolved oxygen (DO) problems are a major water quality concern in the lower Cape Fear
River and its estuary, and several of the tributary streams (Mallin et al. 1999; 2000; 2001a;
2001b; 2002a; 2002b; 2003; 2004; 2005). Concentrations in 2005 ranged from 0.2 to 17.2
mg/L and station annual means ranged from 4.0 to 9.5 mg/L (Table 2.5). Average annual
DO levels at the river channel stations for 2005 were slightly higher than the average for
1996-2004 (Figure 2.2), possibly due to the lack of major hurricane activity and
subsequent pollutant input in the watershed last year. Dissolved oxygen levels were
lowest during the summer (Table 2.5), often falling below the state standard of 5.0 mg/L at
several river and upper estuary stations. Working synergistically to lower oxygen levels
are two factors: lower oxygen carrying capacity in warmer water and increased bacterial
12
respiration (or biochemical oxygen demand, BOD), due to higher temperatures in summer.
These hypoxic conditions could have negative impacts on the biota in the Cape Fear
River.
There is a dissolved oxygen sag in the main river channel that begins at DP below a paper
mill discharge and persists into the mesohaline portion of the estuary (Fig. 2.2). Mean
oxygen levels were highest at the upper river stations NC11 and AC and in the middle to
lower estuary at station M23. Lowest mainstem mean 2005 DO levels occurred at the
lower river and upper estuary stations NAV and HB (7.1 mg/L). Discharge of high BOD
waste from the paper/pulp mill just above the AC station (Mallin et al. 2003), as well as
inflow of blackwater from the Northeast Cape Fear and Black Rivers, help to diminish
oxygen in the upper estuary. As the water reaches the lower estuary higher algal
productivity, mixing and ocean dilution help alleviate oxygen problems.
The Northeast Cape Fear and Black Rivers generally have lower DO levels than the
mainstem Cape Fear River (NCF117 2005 mean = 6.6, NCF6 = 6.9, B210 2005 mean =
7.1). These rivers are classified as blackwater systems because of their tea colored water.
As the water passes through swamps en route to the river channel, tannins from decaying
vegetation leach into the water, resulting in the observed color. Decaying vegetation on
the swamp floor has an elevated biochemical oxygen demand and usurps oxygen from the
water, leading to naturally low dissolved oxygen levels. Runoff from concentrated animal
feeding operations (CAFOs) may also contribute to chronic low dissolved oxygen levels in
these blackwater rivers (Mallin et al. 1998; 1999; 2006; Mallin 2000). The Northeast Cape
Fear River in general seems to be more oxygen stressed than the Black River; in 2005
NCF117 had DO concentrations below 4.0 mg/L 33% of the time sampled, while during
that same period B210 had DO below 4.0 mg/L 0% of the occasions sampled (Table 2.5)
Several stream stations were severely stressed in terms of low dissolved oxygen during
the year 2005. ANC had DO levels below 4.0 mg/L 50% of the occasions sampled, NC403
33%, GS 67%, BCRR 42% and SR 58% (Table 2.5). Some of this can be attributed to low
water conditions and some potentially to CAFO runoff; however point-source discharges
also likely contribute to low dissolved oxygen levels at NC403 and possibly SR, especially
via nutrient loading (Mallin et al. 2001a; 2002a; 2004). Smith Creek had DO levels below
the tidal water standard of 5.0 mg/L 42% of the time.
Field Turbidity
Turbidity levels ranged from 0 to 55 nephelometric turbidity units (NTU) and station annual
means ranged from 1 to 23 NTU (Table 2.6). Annual mean turbidity levels for 2005 were
considerably lower than the long-term average (Fig. 2.3) probably a result of low rainfall.
Highest mean turbidities were at the upper river sites N11, AC and DP (17-19 NTU) with
turbidities gradually decreases downstream through the estuary, except for at the upper
estuarine station NAV (23 NTU – Figure 2.3). This probably reflected the peak of 55 NTU
seen in November (Table 2.6). Turbidity was lower in the blackwater tributaries (Northeast
Cape Fear River and Black River) than in the mainstem river.
13
Note: In addition to the laboratory-analyzed turbidity, the LCFRP uses nephelometers
designed for field use, which allows us to acquire in situ turbidity from a natural situation.
North Carolina regulatory agencies are required to use turbidity values from water samples
removed from the natural system, put on ice until arrival at a State-certified laboratory, and
analyzed using laboratory nephelometers. Standard Methods notes that transport of
samples and temperature change alters true turbidity readings. Our analysis of samples
using both methods shows that lab turbidity is nearly always lower than field turbidity.
Total Suspended Solids
Total suspended solid (TSS) values system wide ranged from 1 to 85 mg/L with station
annual means from 1.6 to 26.5 mg/L (Table 2.7). For the river channel stations TSS was
highest in the upper estuary at NAV, next in the upper river and decreasing through the
estuary. Although total suspended solids (TSS) and turbidity both quantify suspended
material in the water column, they do not always go hand in hand. High TSS does not
mean high turbidity and vice versa. This anomaly may be explained by the fact that fine
clay particles are effective at dispersing light and causing high turbidity readings, while not
resulting in high TSS. On the other hand, large organic or inorganic particles may be less
effective at dispersing light, yet their greater mass results in high TSS levels.
Light Attenuation
The attenuation of solar irradiance through the water column is measured by a logarithmic
function (k) per meter. The higher this light attenuation coefficient is the more strongly light
is attenuated (through absorbance or reflection) in the water column. River and estuary
light attenuation coefficients ranged from 0.88 to 10.09/m and station annual means
ranged from 1.75 at M18 to 4.48 /m at NCF6 (Table 2.8). Annual light attenuation means
for this monitoring period were similar to those of the nine-year period 1996-2004 (Figure
2.4).
High light attenuation did not always coincide with high turbidity. Blackwater, though low in
turbidity, will attenuate light through absorption of solar irradiance. At NCF6 and BBT,
blackwater stations with moderate turbidity levels, light attenuation was high. Compared to
other North Carolina estuaries the Cape Fear has high average light attenuation. The high
average light attenuation is a major reason why phytoplankton production in the major
rivers and the estuary of the LCFR is generally low. Whether caused by turbidity or water
color this attenuation tends to limit light availability to the phytoplankton (Mallin et al. 1997;
1999; 2004).
Chemical Parameters – Nutrients
Total Nitrogen
Total nitrogen (TN) ranged from 150 to 11,260 g/L and station annual means ranged from
587 to 3,945 g/L (Table 2.9). Mean total nitrogen in 2005 was similar to the nine-year
mean at all main channel stations (Figure 2.5). Previous research (Mallin et al. 1999) has
14
shown a positive correlation between river flow and TN in the Cape Fear system. Total
nitrogen concentrations remained fairly constant down the river and declined from midestuary into the lower estuary, most likely reflecting uptake of nitrogen into the food chain
through algal productivity and subsequent grazing by planktivores as well as through
dilution and marsh denitrfication. The blackwater rivers maintained TN concentrations
somewhat lower than those found in the mainstem Cape Fear River. One stream station,
BC117, had a very high mean of 3,945 g/L, likely from the upstream Town of Burgaw
wastewater discharge. ANC, PB, and SAR also had comparatively high TN values among
the stream stations. Temporal patterns for TN were not evident.
Nitrate+Nitrite
Nitrate+nitrite (henceforth referred to as nitrate) is the main species of inorganic nitrogen in
the Lower Cape Fear River. Concentrations system wide ranged from 5 (detection limit) to
9,950 g/L and station annual means ranged from 23 to 2,958 g/L (Table 2.10). Station
annual nitrate means for the 2005 monitoring period were slightly lower than the nine-year
means (Figure 2.6). The highest riverine nitrate levels were at NC11 (605 g/L) indicating
that much of this nutrient is imported from upstream. Moving downstream from NC11,
nitrate levels decrease most likely as a result of uptake by primary producers, microbial
denitrification in riparian marshes and tidal dilution. The blackwater rivers carried low
loads of nitrate compared to the mainstem Cape Fear stations, though the Northeast Cape
Fear River (NCF117 mean = 237 g/L) had higher nitrate than the Black River (B210 =
152 g/L). No clear temporal pattern was observable for nitrate.
Several stream stations showed high levels of nitrate on occasion including SAR, NC403,
PB, BC117, 6RC and BRN. NC403 and PB are downstream of industrial wastewater
discharges and SAR and 6RC primarily receive non-point agricultural or animal waste
drainage. BC117 frequently showed high nitrate levels. The Town of Burgaw wastewater
plant, upstream of BC117, has no nitrate discharge limits. Over the past several years a
considerable number of experiments have been carried out by UNCW researchers to
assess the effects of nutrient additions to water collected from blackwater streams and
rivers (i.e. the Black and Northeast Cape Fear Rivers, and Colly and Great Coharie
Creeks). These experiments have collectively found that additions of nitrogen (as either
nitrate, ammonium, or urea) significantly stimulate phytoplankton production and BOD
increases. Critical levels of these nutrients were in the range of 0.2 to 0.5 mg/L as N
(Mallin et al. 1998; Mallin et al. 2001a; Mallin et al. 2002a, Mallin et al. 2004). Thus, we
conservatively consider nitrate concentrations exceeding 0.5 mg/L as N in Cape Fear
watershed streams to be potentially problematic to the streams environmental health.
Blackwater streams where we periodically see concentrations of this magnitude include
6RC, SAR, BC117, NC403, and PB.
Ammonium
Ammonium concentrations ranged from 10 (detection limit) to 640 g/L and station annual
means ranged from 22 to 103 g/L (Table 2.11). The 2005 monitoring period mean
ammonium levels were considerably lower than the nine-year means at the channel
15
stations (Figure 2.7). River areas with the highest mean ammonium levels this monitoring
period included AC, which is below a pulp mill discharge, and DP, located downstream of
AC. Ocean dilution accounts for decreasing levels in the lower estuary. At the stream
stations, areas with periodic high levels of ammonium include LVC2, ANC, SAR, BRN and
PB.
Total Kjeldahl Nitrogen
Total Kjeldahl Nitrogen (TKN) is a measure of the total concentration of organic nitrogen
plus ammonium. TKN ranged from 100 to 3,110 g/L and station annual means ranged
from 472 to 1,447 g/L (Table 2.12). Mean TKN for 2004 was similar to or slightly higher
than the nine-year mean at the channel stations (Figure 2.8). TKN concentration drops
down through the estuary, likely due to ocean dilution and food chain uptake of nitrogen.
Measured TKN levels in the blackwater rivers are usually higher than in the mainstem
Cape Fear River as a result of the high concentration of organic materials dissolved in the
water (Figure 2.8). The stream stations typically have higher TKN as a result of the
influence of swamp water with high organic and ammonium content. There were
somewhat higher TKN levels during summer months.
Total Phosphorus
Total phosphorus (TP) concentrations ranged from 10 (detection limit) to 2,130 g/L and
station annual means ranged from 21 to 928 g/L (Table 2.13). Mean TP for 2005 was
lower than the nine-year mean at almost all channel stations (Figure 2.9), potentially a
result of lower runoff and river discharge. In the river TP is highest at the upper riverine
channel stations and declines downstream into the estuary. Some of this decline is
attributable to the settling of phosphorus-bearing turbidity, yet incorporation of phosphorus
into the food chain is also responsible. A temporal pattern of higher summer TP is a result
of increasing orthophosphate during the summer.
The experiments discussed above in the nitrate subsection also involved additions of
phosphorus, either as inorganic orthophosphate or a combination of inorganic plus organic
P. The experiments showed that additions of P exceeding 0.5 mg/L led to significant
increases in bacterial counts, as well as significant increases in BOD over control. Thus,
we consider concentrations of phosphorus above 0.5 to be potentially problematic to
blackwater streams. Streams periodically exceeding this critical concentration included
GS, NC403, PB, GCO and BC117. Some of these stations (BC117, NC403) are
downstream of industrial or wastewater discharges, while GS and GCO are in non-point
agricultural areas.
16
Orthophosphate
Orthophosphate ranged from 0 to 1,950 g/L and station annual means ranged from 8 to
834 g/L (Table 2.14). The 2005 annual means at the channel stations were in general
slightly lower than the nine-year means (Figure 2.10).
Much of the orthophosphate load is imported into the Lower Cape Fear system from
upstream areas, as NC11 typically has the highest levels. The Northeast Cape Fear River
had higher orthophosphate levels than the Black River. Orthophosphate can bind to
suspended materials and is transported downstream via turbidity; thus high levels of
turbidity at the uppermost river stations may be an important factor in the high
orthophosphate levels. Turbidity declines toward the estuary because of settling, and
orthophosphate concentration also declines. In the estuary, primary productivity helps
reduce orthophosphate concentrations by assimilation into biomass. Orthophosphate
levels typically reach maximum concentrations during summertime, when anoxic sediment
releases bound phosphorus. Also, in the Cape Fear Estuary, summer algal productivity is
limited by nitrogen, thereby allowing the accumulation of orthophosphate (Mallin et al.
1997; 1999). In spring, productivity in the estuary is usually limited by phosphorus (Mallin
et al. 1997; 1999).
The stream station BC117 had high orthophosphate levels while ANC and GCO had
moderate levels. BC117 is strongly influenced by industrial and municipal wastewater
discharges, and ANC and GCO by agriculture/animal waste runoff.
Chemical Parameters - EPA Priority Pollutant Metals
Aluminum levels in the Lower Cape Fear system were generally higher in the upper river
and decreased toward the lower estuary (Table 2.15). Stream stations were generally low
except COL, which is considered pristine swamp water. There is no North Carolina
aquatic standard for aluminum.
Arsenic, cadmium, and chromium all maintained concentrations below detection limits at
all stations (except As had measurable levels at M35, M23 and M18 in the lower estuary)
throughout the year (Tables 2.16, 2.17, and 2.18). The As concentrations were all below
the N.C. standard.
Copper concentrations frequently exceeded the state tidal saltwater standard of 3 g/L at
estuarine stations M54, M35, M23 and M18 (Table 2.19). The freshwater standard of 7
g/L was not exceeded at the stream stations sampled.
The LCFRP is an iron-rich system (Table 2.20). Stations NC11, DP, NAV, SAR, LRC and
GCO maintained average iron concentrations above the state standard of 1000 g/L. Iron
concentrations generally decreased down-estuary.
Water-column concentrations of lead, mercury, and nickel were below the analytical
detection limit except for nickel, which remained below the N.C. state standard (Tables
17
2.21, 2.22, 2.23). The Ni standard for tidal saltwater was exceeded on several occasions
at M35, M23 and M18 (Table 2.23).
Zinc concentrations remained below the state standard at all stations (Table 2.24).
Biological Parameters
Chlorophyll a
During this monitoring period chlorophyll a was generally low to moderate at the river and
estuarine stations (Table 2.25). System wide, chlorophyll a ranged from 0.1 to 148.5 g/L
and station annual means ranged from 0.4 –19.3 g/L. Production of chlorophyll a
biomass is low to moderate in this system primarily because of light limitation by turbidity in
the mainstem and high organic color and low inorganic nutrients in the blackwater rivers.
Spatially, highest values are normally found in the mid-to-lower estuary stations because
light becomes more available downstream of the estuarine turbidity maximum (Figure
2.11). The peak estuarine bloom of 32 g/L was seen at M42, in the mid-to-lower estuary.
Chlorophyll a production is extremely limited in the large blackwater tributaries. Highest
chlorophyll a concentrations were found during spring and summer. Main channel
chlorophyll a concentrations in 2005 were generally higher than long-term mean
concentrations (Fig. 2.11), possibly a result of lower rainfall and less turbid waters..
Substantial phytoplankton blooms occasionally occur at the stream stations (Table 2.25).
These streams are generally shallow, so vertical mixing does not carry phytoplankton cells
down below the critical depth where respiration exceeds photosynthesis. Thus, when flow
conditions permit, elevated nutrient conditions (such as are periodically found in these
stream stations) can lead to algal blooms. In areas where the forest canopy opens up
large blooms can occur. When blooms occur in blackwater stream stations they can
become sources of BOD upon death and decay, reducing further the low summer
dissolved oxygen conditions common to these waters (Mallin et al. 2001; 2002; 2004).
Stream algal blooms in 2005 occurred at GS, PB, and BCRR.
Biochemical Oxygen Demand
For the main stem river, mean annual five-day biochemical oxygen demand (BOD5)
concentrations were highest at AC, on average about 15% higher than at NC11 suggesting
influence from the pulp/paper mill inputs (Table 2.26). BOD was somewhat lower during
the winter.
From 2000 until April 2004 we performed a project aimed at assessing rural Black River
system stream contributions to BOD. In May 2004 we changed the stream sampling to the
Northeast Cape Fear River watershed. Results of BOD analyses from several stream
stations can be seen in Table 2.26. The data show generally greater BOD concentrations
at the Northeast Cape Fear Watershed streams than the Black River Watershed streams.
SAR, GS and N403 all showed large (> 3.2 mg/L) individual BOD5 measurements during
18
2005. Station N403 is below a point source, but the other two sites are non-point runoff
areas.
Fecal Coliform Bacteria
Fecal coliform (FC) bacterial counts ranged from 1 to >6,000 CFU/100 mL and station
annual geometric means ranged from 4 to 319 CFU/100 mL (Table 2.27). The state
human contact standard (200 CFU/100 mL) was exceeded only once at the channel
stations in 2005. FC counts in 2005 were much lower at the Cape Fear River and estuary
stations compared with the nine-year average (Figure 2.12), likely a result of the low
rainfall. FC bacteria show a notable spatial trend of highest counts in the upper estuarylower river area including stations NAV, HB, BRR, M61 and M54.
Most stream stations surpassed the state standard for human contact of 200 CFU/100 mL
on at least one occasion and several were particularly problematic. During 2005 PB
exceeded the state standard 58% of the time, BCRR 42%, BC117 and GS 33%, and ANC
and SR exceeded the standard 25% of the time. BC117 and PB are located below point
source discharges and the other sites are primarily influenced by non-point source
pollution.
2.4 - References Cited
APHA. 1995. Standard Methods for the Examination of Water and Wastewater, 19th ed.
American Public Health Association, Washington, D.C.
Mallin, M.A., L.B. Cahoon, M.R. McIver, D.C. Parsons and G.C. Shank. 1997. Nutrient
limitation and eutrophication potential in the Cape Fear and New River Estuaries.
Report No. 313. Water Resources Research Institute of the University of North Carolina,
Raleigh, N.C.
Mallin, M.A., L.B. Cahoon, D.C. Parsons and S.H. Ensign. 1998. Effect of organic and
inorganic nutrient loading on photosynthetic and heterotrophic plankton communities in
blackwater rivers. Report No. 315. Water Resources Research Institute of the
University of North Carolina, Raleigh, N.C.
Mallin, M.A., L.B. Cahoon, M.R. McIver, D.C. Parsons and G.C. Shank. 1999. Alternation
of factors limiting phytoplankton production in the Cape Fear Estuary. Estuaries
22:985-996.
Mallin, M.A. 2000. Impacts of industrial-scale swine and poultry production on rivers and
estuaries. American Scientist 88:26-37.
Mallin, M.A., M.H. Posey, M.R. McIver, S.H. Ensign, T.D. Alphin, M.S. Williams, M.L.
Moser and J.F. Merritt. 2000. Environmental Assessment of the Lower Cape Fear River
19
System, 1999-2000. CMS Report No. 00-01, Center for Marine Science, University of
North Carolina at Wilmington, Wilmington, N.C.
Mallin, M.A., L.B. Cahoon, D.C. Parsons and S.H. Ensign. 2001a. Effect of nitrogen and
phosphorus loading on plankton in Coastal Plain blackwater streams. Journal of
Freshwater Ecology 16:455-466.
Mallin, M.A., M.H. Posey, T.E. Lankford, M.R. McIver, S.H. Ensign, T.D. Alphin, M.S.
Williams, M.L. Moser and J.F. Merritt. 2001b. Environmental Assessment of the Lower
Cape Fear River System, 2000-2001. CMS Report No. 01-01, Center for Marine
Science, University of North Carolina at Wilmington, Wilmington, N.C.
Mallin, M.A., L.B. Cahoon, M.R. McIver and S.H. Ensign. 2002a. Seeking science-based
nutrient standards for coastal blackwater stream systems. Report No. 341. Water
Resources Research Institute of the University of North Carolina, Raleigh, N.C.
Mallin, M.A., M.H. Posey, T.E. Lankford, M.R. McIver, H.A. CoVan, T.D. Alphin, M.S.
Williams and J.F. Merritt. 2002b. Environmental Assessment of the Lower Cape Fear
River System, 2001-2002. CMS Report No. 02-02, Center for Marine Science,
University of North Carolina at Wilmington, Wilmington, N.C.
Mallin, M.A., M.R. McIver, H.A. Wells, M.S. Williams, T.E. Lankford and J.F. Merritt. 2003.
Environmental Assessment of the Lower Cape Fear River System, 2002-2003. CMS
Report No. 03-03, Center for Marine Science, University of North Carolina at
Wilmington, Wilmington, N.C.
Mallin, M.A., M.R. McIver, S.H. Ensign and L.B. Cahoon. 2004. Photosynthetic and
heterotrophic impacts of nutrient loading to blackwater streams. Ecological Applications
14:823-838.
Mallin, M.A., M.R. McIver, T.D. Alphin, M.H. Posey and J.F. Merritt. 2005. Environmental
Assessment of the Lower Cape Fear River System, 2003-2004. CMS Report No. 05-02,
Center for Marine Science, University of North Carolina at Wilmington, Wilmington, N.C.
U.S. EPA 1997. Methods for the Determination of Chemical Substances in Marine and
Estuarine Environmental Matrices, 2nd Ed. EPA/600/R-97/072. National Exposure
Research Laboratory, Office of Research and Development, U.S. Environmental
Protection Agency, Cincinnati, Ohio.
Welschmeyer, N.A. 1994. Fluorometric analysis of chlorophyll a in the presence of
chlorophyll b and phaeopigments. Limnology and Oceanography 39:1985-1993.
20
Table 2.1 Water Temperature (oC) at the LCFRP stations for 2005.
month NAV
JAN
12.0
FEB
10.8
MAR 10.9
APR
16.7
MAY 19.1
JUN
25.2
JUL
29.5
AUG 28.9
SEP
27.3
OCT
25.9
NOV
16.7
DEC
8.9
mean 19.3
std dev 7.4
max
29.5
min
8.9
HB
12.5
11.1
11.3
16.5
19.5
27.6
30.5
29.2
27.6
25.9
17.4
8.8
19.8
7.6
30.5
8.8
BRR
12.3
11.9
11.2
16.7
19.6
27.7
31.1
29.4
27.9
25.7
17.3
9.1
20.0
7.7
31.1
9.1
M61
12.4
11.8
11.4
17.1
20.6
27.5
31.1
29.8
27.5
25.8
18.0
10.3
20.3
7.5
31.1
10.3
M54
12.5
11.9
11.3
17.2
19.7
25.9
29.7
29.7
26.8
25.5
18.5
10.2
19.9
7.1
29.7
10.2
M42
13.0
12.2
11.3
17.0
19.7
26.9
30.5
29.2
26.5
25.5
18.1
10.6
20.0
7.1
30.5
10.6
M35
13.7
12.0
11.4
17.1
19.8
26.6
29.8
29.1
26.3
25.4
18.0
10.8
20.0
6.9
29.8
10.8
month ANC
JAN
13.1
FEB
11.9
MAR
7.9
APR
19.2
MAY 17.7
JUN
25.1
JUL
26.3
AUG 25.2
SEP
25.2
OCT
21.7
NOV
17.4
DEC
5.4
mean 18.0
std dev 6.8
max
26.3
min
5.4
SAR
13.9
12.2
7.7
19.7
17.5
26.4
26.9
25.7
24.8
19.8
17.2
3.8
18.0
7.2
26.9
3.8
GS
13.8
12.3
7.2
20.3
16.9
24.9
26.1
25.8
24.3
19.8
16.9
3.7
17.7
7.0
26.1
3.7
NC403
13.5
11.1
8.3
18.5
18.0
PB
15.3
13.0
9.2
19.0
18.3
28.1
27.2
30.3
26.3
22.0
18.1
4.2
19.3
7.7
30.3
4.2
LRC
15.8
12.6
11.6
18.8
16.0
26.9
25.1
27.5
25.8
21.4
16.1
7.0
18.7
6.4
27.5
7.0
ROC BC117 BCRR
13.8
17.5
13.6
12.5
13.7
12.5
9.8
12.8
10.3
18.8
16.8
16.3
17.1
18.0
17.4
26.1
26.7
26.1
25.3
25.1
24.6
27.4
29.0
26.2
25.4
26.7
24.9
21.3
21.5
21.2
15.5
18.7
15.1
5.7
11.0
6.0
18.2
19.8
17.9
6.7
5.7
6.4
27.4
29.0
26.2
5.7
11.0
6.0
24.7
20.6
16.5
4.8
15.1
5.9
24.7
4.8
M23
13.2
11.8
11.6
16.6
19.1
25.9
29.2
29.2
26.4
25.1
18.4
10.8
19.8
6.8
29.2
10.8
M18
12.7
11.3
11.5
16.5
18.8
25.8
29.5
28.8
27.1
25.8
18.5
11.3
19.8
6.9
29.5
11.3
SPD
13.1
11.9
11.7
16.6
18.8
25.7
29.7
28.9
26.4
25.1
17.2
10.8
19.7
6.8
29.7
10.8
month NC11
JAN
12.0
FEB
7.2
MAR
9.3
APR
15.9
MAY 19.6
JUN
25.4
JUL
29.8
AUG 27.6
SEP
28.4
OCT
25.9
NOV
17.2
DEC
7.7
mean 18.8
std dev 8.1
max
29.8
min
7.2
month
JAN
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
mean
std dev
max
min
6RC
12.6
7.4
9.4
14.8
18.1
23.9
26.9
24.6
25.0
21.5
11.4
6.9
16.9
7.0
26.9
6.9
LCO
12.6
6.7
9.1
15.0
18.3
24.2
26.9
25.4
25.4
21.7
11.7
6.2
16.9
7.4
26.9
6.2
AC
12.3
7.2
9.4
16.2
20.4
25.3
29.6
27.9
28.4
25.8
17.3
7.9
19.0
8.1
29.6
7.2
DP
12.7
7.4
9.5
16.5
20.4
26.2
29.5
27.7
27.9
25.5
17.3
8.0
19.1
7.9
29.5
7.4
BBT
12.7
8.1
10.2
17.0
20.2
25.6
28.9
27.0
27.8
25.4
16.5
7.8
18.9
7.6
28.9
7.8
IC
12.4
8.0
10.2
17.1
20.3
25.9
29.3
30.2
28.1
25.7
16.6
8.0
19.3
8.1
30.2
8.0
GCO
12.0
7.4
9.6
14.5
17.9
24.0
26.9
25.0
24.7
21.2
11.5
5.8
16.7
7.2
26.9
5.8
SR
11.5
7.1
9.5
15.2
18.1
24.2
25.5
24.7
24.9
22.1
11.0
5.7
16.6
7.2
25.5
5.7
BRN
13.6
8.9
11.7
16.0
18.7
24.4
25.0
25.5
25.1
22.3
12.7
7.6
17.6
6.4
25.5
7.6
HAM
13.0
7.9
10.7
15.5
17.7
23.4
23.9
24.7
23.7
20.7
11.7
6.9
16.7
6.3
24.7
6.9
NCF6
12.6
8.6
10.5
18.3
19.8
25.7
29.5
30.3
27.9
25.7
16.9
10.0
19.7
7.7
30.3
8.6
month NCF117 B210
JAN
12.1
13.7
FEB
8.6
9.5
MAR
10.5
10.0
APR
18.3
17.8
MAY
20.4
20.1
JUN
25.4
27.7
JUL
29.1
28.6
AUG
29.9
25.3
SEP
27.7
25.3
OCT
25.3
23.9
NOV
14.1
14.0
DEC
8.6
5.9
mean
19.2
18.5
std dev
7.8
7.5
max
29.9
28.6
min
8.6
5.9
COL
13.1
10.1
9.2
17.4
16.4
24.3
25.9
24.4
23.0
22.5
13.8
4.9
17.1
6.7
25.9
4.9
LVC2 SC-CH
13.9
7.5
9.5
8.5
10.2
13.2
17.3
18.1
19.3
22.6
24.6
30.0
27.6
29.9
26.0
29.9
25.3
26.8
23.0
25.9
12.7
16.8
7.0
9.4
18.0
19.9
6.9
8.4
27.6
30.0
7.0
7.5
21
Table 2.2 Salinity (psu) at the LCFRP estuarine stations for 2005.
month
NAV
HB
BRR
M61
M54
M42
M35
M23
M18
SPD
NCF6
JAN
4.6
4.8
5.0
7.9
11.4
16.1
22.8
28.6
34.7
28.7
3.1
FEB
0.1
2.5
3.5
9.0
10.0
11.8
14.0
23.1
27.4
27.4
2.6
MAR
0.1
0.1
0.1
0.6
1.8
4.1
12.0
24.8
31.4
23.4
0.1
APR
0.1
0.1
0.1
0.1
0.4
1.2
2.5
9.8
12.4
19.4
0.1
MAY
0.1
1.8
3.2
7.8
9.5
12.6
15.1
26.2
29.6
26.9
0.7
JUN
0.1
0.3
0.6
3.0
6.6
10.1
16.8
26.6
31.0
26.5
0.1
JUL
0.2
5.3
5.2
9.0
12.9
13.6
20.2
29.3
31.9
27.3
0.5
AUG
0.1
0.1
0.2
4.1
4.8
7.3
25.2
20.3
24.3
26.6
0.8
SEP
13.4
17.5
10.8
17.5
21.9
26.1
27.1
32.5
34.5
32.2
10.9
OCT
9.1
9.5
10.4
13.9
17.2
21.0
24.7
30.2
34.2
28.6
10.0
NOV
1.4
4.4
4.9
9.7
11.3
12.4
17.0
23.4
26.1
25.2
0.5
DEC
0.1
0.1
0.1
2.1
2.8
5.2
7.8
15.8
20.6
24.2
0.1
mean
2.5
3.9
3.7
7.1
9.2
11.8
17.1
24.2
28.2
26.4
2.5
std dev
4.2
5.0
3.7
5.1
6.1
6.8
7.1
6.2
6.3
3.0
3.7
max
13.4
17.5
10.8
17.5
21.9
26.1
27.1
32.5
34.7
32.2
10.9
min
0.1
0.1
0.1
0.1
0.4
1.2
2.5
9.8
12.4
19.4
0.1
22
Table 2.3 Specific Conductivity (mS/cm) at the LCFRP stations for 2005.
month
JAN
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
mean
std dev
max
min
NAV
8.17
0.27
0.15
0.11
0.21
0.21
0.51
0.14
22.25
15.36
2.68
0.15
4.18
7.04
22.25
0.11
HB
8.40
4.65
0.17
0.11
3.39
0.68
9.57
0.24
28.26
16.29
7.67
0.14
6.63
8.12
28.26
0.11
BRR
8.97
6.35
0.16
0.12
5.86
1.11
9.44
0.33
18.22
17.75
8.67
0.23
6.43
6.27
18.22
0.12
M61
13.62
15.35
1.13
0.13
13.47
5.57
15.48
7.53
28.51
23.01
16.47
3.94
12.02
8.30
28.51
0.13
M54
19.04
17.00
3.34
0.76
16.40
11.62
21.64
8.60
34.88
27.96
18.96
5.19
15.45
9.70
34.88
0.76
M42
26.25
19.71
7.41
2.25
21.02
17.10
22.74
12.74
40.86
33.52
20.71
9.19
19.46
10.46
40.86
2.25
M35
36.00
22.85
20.02
4.66
24.75
27.36
32.55
39.80
42.31
38.80
27.75
13.45
27.52
10.80
42.31
4.66
month
JAN
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
mean
std dev
max
min
ANC
0.10
0.11
0.10
0.08
0.09
0.09
0.12
0.10
0.17
0.09
0.07
0.09
0.10
0.02
0.17
0.07
SAR
0.20
0.17
0.18
0.16
0.18
0.19
0.21
0.24
0.29
0.18
0.23
0.19
0.20
0.03
0.29
0.16
GS
0.19
0.16
0.18
0.15
0.17
0.20
0.22
0.21
0.22
0.19
0.22
0.18
0.19
0.02
0.22
0.15
NC403
0.44
0.48
0.48
0.39
0.41
PB
1.30
1.91
0.92
1.12
3.64
4.03
1.23
2.78
2.43
2.18
3.93
0.94
2.20
1.12
4.03
0.92
LRC
0.14
0.16
0.13
0.12
0.12
0.11
0.14
0.12
0.15
0.12
0.14
0.13
0.13
0.01
0.16
0.11
ROC
0.14
0.13
0.13
0.11
0.13
0.12
0.14
0.10
0.14
0.14
0.16
0.14
0.13
0.02
0.16
0.10
0.51
0.39
0.45
0.35
0.43
0.05
0.51
0.35
M23
44.00
36.50
39.04
16.60
40.93
41.50
45.30
32.59
49.47
46.46
36.87
25.83
37.92
8.91
49.47
16.60
M18
52.68
42.77
48.30
20.72
46.62
47.67
48.99
38.45
52.48
51.95
40.65
32.95
43.69
9.04
52.68
20.72
BC117 BCRR
0.72
0.26
0.41
0.22
0.45
0.20
0.24
0.11
0.90
0.25
0.78
0.21
0.60
0.30
0.58
0.23
0.56
0.09
0.13
0.08
0.86
0.19
0.61
0.15
0.57
0.19
0.23
0.07
0.90
0.30
0.13
0.08
SPD
44.48
42.62
37.06
31.17
41.77
41.38
42.63
41.60
49.27
44.27
39.51
38.25
41.17
4.27
49.27
31.17
month NC11
JAN
0.12
FEB
0.12
MAR
0.13
APR
0.10
MAY
0.11
JUN
0.13
JUL
0.14
AUG
0.11
SEP
0.14
OCT
0.17
NOV
0.14
DEC
0.10
mean
0.13
std dev 0.02
max
0.17
min
0.10
month
JAN
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
mean
std dev
max
min
6RC
0.13
0.12
0.12
0.11
0.12
0.11
0.12
0.11
0.14
0.12
0.13
0.13
0.12
0.01
0.14
0.11
LCO
0.09
0.09
0.08
0.08
0.08
0.08
0.08
0.07
0.08
0.08
0.09
0.09
0.08
0.01
0.09
0.07
GCO
0.15
0.14
0.13
0.11
0.16
0.19
0.16
0.11
0.22
0.27
0.17
0.13
0.16
0.05
0.27
0.11
AC
0.12
0.15
0.18
0.10
0.32
0.12
0.15
0.15
0.30
0.34
0.16
0.15
0.19
0.08
0.34
0.10
DP
0.14
0.14
0.16
0.10
0.17
0.16
0.24
0.12
0.22
0.25
0.31
0.13
0.18
0.06
0.31
0.10
BBT
0.14
0.13
0.13
0.09
0.14
0.15
0.14
0.07
0.21
0.24
0.14
0.12
0.14
0.04
0.24
0.07
SR
0.09
0.08
0.07
0.07
0.08
0.09
0.14
0.10
0.14
0.15
0.15
0.13
0.11
0.03
0.15
0.07
BRN
0.13
0.12
0.14
0.11
0.11
0.08
0.11
0.09
0.12
0.12
0.13
0.14
0.12
0.02
0.14
0.08
HAM
0.15
0.13
0.12
0.12
0.15
0.12
0.14
0.11
0.16
0.17
0.15
0.14
0.14
0.02
0.17
0.11
IC
0.16
0.14
0.14
0.10
0.17
0.16
0.18
0.10
0.26
0.35
0.22
0.13
0.18
0.07
0.35
0.10
NCF6
6.41
4.95
0.15
0.11
1.30
0.26
0.91
1.66
18.51
17.20
1.01
0.18
4.39
6.32
18.51
0.11
month NCF117 B210
JAN
0.16
0.09
FEB
0.14
0.09
MAR
0.12
0.08
APR
0.11
0.10
MAY
0.15
0.08
JUN
0.12
0.09
JUL
0.14
0.09
AUG
0.14
0.06
SEP
0.19
0.08
OCT
0.15
0.10
NOV
0.13
0.10
DEC
0.14
0.10
mean
0.14
0.09
std dev 0.02
0.01
max
0.19
0.10
min
0.11
0.06
COL
0.07
0.07
0.07
0.07
0.07
0.06
0.07
0.06
0.07
0.07
0.07
0.07
0.07
0.00
0.07
0.06
LVC2 SC-CH
0.13
0.20
0.12
3.90
0.12
3.12
0.08
0.16
0.15
3.94
0.06
0.80
0.14
5.30
0.10
1.78
0.11
8.24
0.10
17.42
0.09
1.36
0.10
0.34
0.11
3.88
0.02
4.70
0.15
17.42
0.06
0.16
23
Table 2.4 pH at the LCFRP stations for 2005.
month
JAN
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
median
std dev
max
min
NAV
HB
BRR
M61
M54
M42
M35
M23
M18
SPD
7.2
7.8
7.5
7.0
7.1
7.3
6.7
6.7
7.4
7.1
6.8
7.0
7.1
0.3
7.8
6.7
7.3
7.8
7.6
6.7
7.1
7.5
7.3
6.7
7.5
7.0
6.8
6.9
7.2
0.4
7.8
6.7
7.2
7.6
7.8
6.9
7.2
7.3
7.7
7.0
7.5
7.1
6.8
7.0
7.2
0.3
7.8
6.8
7.4
7.8
7.7
6.7
7.4
7.2
7.4
7.1
7.6
7.2
7.0
7.2
7.3
0.3
7.8
6.7
7.7
7.8
8.0
7.0
7.5
7.3
7.6
7.3
7.8
7.5
7.2
7.3
7.2
0.3
8.0
7.0
8.0
8.0
8.1
7.1
7.6
7.5
7.8
7.5
7.8
7.7
7.3
7.5
7.7
0.3
8.1
7.1
8.1
8.1
8.1
7.4
7.7
7.7
7.8
7.5
7.8
7.8
7.6
7.7
7.8
0.2
8.1
7.4
8.1
8.2
8.1
7.8
7.7
7.8
7.8
7.5
7.9
7.9
7.9
8.0
7.9
0.2
8.2
7.5
8.1
8.2
8.0
7.9
7.9
7.8
7.8
7.5
7.8
8.0
8.0
8.1
8.0
0.2
8.2
7.5
8.0
8.1
8.0
7.6
7.7
7.5
7.3
7.2
7.7
7.8
7.7
8.0
7.7
0.3
8.1
7.2
month
JAN
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
median
std dev
max
min
ANC
SAR
GS
NC403
PB
LRC
ROC
6.0
5.3
6.0
5.6
5.6
5.7
6.3
5.6
6.5
5.1
5.3
5.9
5.7
0.4
6.5
5.1
6.7
6.1
6.5
6.6
6.7
6.6
7.0
6.1
6.7
5.6
6.9
6.6
6.6
0.4
7.0
5.6
6.5
6.3
6.6
6.6
6.3
6.4
6.4
6.0
6.3
5.8
6.5
6.6
6.4
0.2
6.6
5.8
6.5
6.3
6.7
6.5
6.3
6.6
6.3
6.6
6.0
6.5
6.6
6.5
6.5
6.7
6.2
6.8
6.5
6.5
0.2
6.8
6.0
7.3
6.9
7.0
7.0
7.2
7.5
7.5
7.3
7.5
6.7
7.1
7.3
7.3
0.2
7.5
6.7
7.1
6.9
7.0
6.7
6.9
7.1
7.2
6.9
7.0
6.1
7.0
7.0
7.0
0.3
7.2
6.1
6.2
5.9
6.4
6.4
6.4
0.2
6.7
5.9
BC117 BCRR
7.9
7.4
8.1
6.7
7.6
7.6
7.6
7.5
7.8
6.3
7.5
7.8
7.6
0.5
8.1
6.3
7.1
7.2
7.9
6.0
7.1
7.2
7.2
7.4
7.3
5.9
6.6
7.3
7.2
0.6
7.9
5.9
month
JAN
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
median
std dev
max
min
month
JAN
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
median
std dev
max
min
NC11
AC
DP
BBT
IC
NCF6
6.9
7.0
7.0
6.6
6.5
6.4
6.5
6.3
7.1
6.9
6.8
6.9
6.9
0.3
7.1
6.3
7.0
7.1
7.2
6.8
6.9
6.6
6.6
6.4
7.2
7.1
6.9
7.0
7.0
0.2
7.2
6.4
6.8
7.1
7.1
6.9
6.8
4.7
6.8
6.4
6.8
6.8
7.1
7.0
6.8
0.6
7.1
4.7
6.8
6.9
7.0
6.6
6.6
6.6
6.7
5.9
6.8
6.8
6.5
6.8
6.8
0.3
7.0
5.9
6.9
7.0
7.0
6.7
6.7
6.7
6.8
6.3
6.8
6.8
6.8
6.9
6.8
0.2
7.0
6.3
7.2
7.0
6.8
6.6
6.6
6.5
6.5
6.4
7.1
6.9
6.4
6.6
6.6
0.3
7.2
6.4
6RC
LCO
GCO
SR
BRN
HAM
7.0
6.0
6.4
6.4
6.5
6.7
7.1
6.0
6.3
6.8
6.7
6.8
6.6
0.3
7.1
6.0
6.6
6.1
6.4
6.4
6.5
6.6
6.7
6.3
6.3
6.8
6.7
5.8
6.5
0.3
6.8
5.8
6.6
6.3
6.5
6.4
6.5
6.6
6.8
6.1
6.3
6.9
6.6
6.3
6.5
0.2
6.9
6.1
6.2
6.1
6.4
6.4
6.3
6.3
6.4
6.0
6.1
6.1
6.1
5.9
6.2
0.2
6.4
5.9
6.8
6.5
6.7
6.7
6.8
6.5
6.9
6.1
6.6
7.1
6.9
6.8
6.8
0.2
7.1
6.1
6.9
6.7
6.7
6.7
6.8
6.6
6.9
6.3
6.6
7.0
7.0
6.9
6.8
0.2
7.0
6.3
month NCF117 B210
JAN
6.4
6.4
FEB
5.4
5.5
MAR
5.5
5.7
APR
6.3
6.1
MAY
6.4
6.0
JUN
6.1
6.3
JUL
6.1
6.0
AUG
6.1
5.2
SEP
6.4
6.2
OCT
5.9
5.7
NOV
6.2
6.3
DEC
6.1
6.2
median
6.1
6.1
std dev
0.3
0.4
max
6.4
6.4
min
5.4
5.2
COL
4.0
3.2
3.6
3.9
3.2
3.9
3.9
3.8
3.7
3.6
4.0
3.8
3.8
0.3
4.0
3.2
LVC2 SC-CH
6.5
5.6
6.0
6.5
6.5
6.0
6.3
5.9
6.4
5.7
6.5
6.0
6.2
0.3
6.5
5.6
7.1
5.7
6.9
6.9
6.8
7.1
6.4
6.8
6.4
6.5
6.8
6.7
6.8
0.4
7.1
5.7
24
Table 2.5 Dissolved Oxygen (mg/L) concentrations at the LCFRP stations for 2005. The NC State standards are 5.0 and 4.0
mg/L for surface water and swampwater, respectively.
month
JAN
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
mean
std dev
max
min
NAV
HB
BRR
M61
M54
M42
M35
M23
M18
SPD
9.6
10.4
10.4
7.7
6.7
5.3
3.9
5.2
5.1
4.1
6.2
10.5
7.1
2.4
10.5
3.9
9.8
10.2
10.2
8.0
6.8
5.6
4.0
5.1
5.0
4.3
5.9
10.5
7.1
2.4
10.5
4.0
9.8
10.4
10.2
7.7
6.8
5.9
5.1
5.2
5.7
5.1
5.9
10.1
7.3
2.1
10.4
5.1
9.5
10.0
10.3
7.4
7.3
5.8
5.7
4.4
5.4
4.9
5.8
9.6
7.2
2.1
10.3
4.4
9.5
10.3
9.8
7.6
7.6
5.7
5.9
4.5
6.6
5.8
6.2
9.9
7.5
1.9
10.3
4.5
9.9
10.7
11.4
7.6
7.8
6.8
6.8
4.9
6.8
6.5
6.4
9.8
8.0
1.9
11.4
4.9
9.6
11.1
11.3
7.7
8.2
7.1
6.4
4.5
6.6
6.6
6.8
9.9
8.0
2.0
11.3
4.5
9.2
11.2
11.1
8.4
8.2
6.9
6.2
5.4
6.7
6.7
7.2
10.0
8.1
1.8
11.2
5.4
8.8
11.0
10.2
8.4
8.1
7.0
6.4
5.6
6.5
6.6
7.3
9.6
8.0
1.6
11.0
5.6
9.2
10.4
11.2
7.8
7.5
6.6
6.5
4.6
6.8
6.4
6.7
9.0
7.7
1.8
11.2
4.6
month
JAN
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
mean
std dev
max
min
ANC
SAR
GS
NC403
PB
LRC
ROC
5.1
7.5
11.2
8.4
3.6
1.4
0.7
1.9
1.8
1.3
4.3
10.1
4.8
3.5
11.2
0.7
8.1
8.4
10.7
6.0
7.7
4.5
5.9
4.3
4.5
4.3
7.8
11.9
7.0
2.4
11.9
4.3
3.1
5.9
10.3
7.1
1.9
2.3
0.4
0.8
0.4
1.9
2.2
11.3
4.0
3.6
11.3
0.4
4.7
5.9
10.4
4.2
4.6
7.5
8.6
10.9
4.1
7.3
6.0
2.1
7.5
5.3
4.0
6.7
10.8
6.7
2.5
10.9
2.1
10.6
10.8
11.9
9.2
10.1
8.2
7.3
8.7
8.8
7.8
9.0
12.1
9.5
1.5
12.1
7.3
9.5
10
11.6
8.1
7.6
5.9
5.2
6.3
5.2
4.7
8.0
12.1
7.9
2.4
12.1
4.7
0.4
1.0
3.8
9.3
4.9
3.1
10.4
0.4
BC117 BCRR
12.7
12.3
17.2
8.2
9.5
8.1
4.6
9.1
7.7
6.9
5.5
11.4
9.4
3.4
17.2
4.6
5.7
9.8
12.2
8.0
5.2
3.5
2.2
3.5
3.2
6.1
3.5
11.5
6.2
3.3
12.2
2.2
month
JAN
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
mean
std dev
max
min
month
JAN
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
mean
std dev
max
min
NC11
AC
DP
BBT
IC
NCF6
12.1
12.4
11.9
9.6
8.4
7.2
6.8
6.6
7.2
6.3
8.2
11.9
9.1
2.3
12.4
6.3
11.8
12.2
11.7
9.4
7.7
6.4
5.7
6.7
6.5
5.8
8.5
11.5
8.7
2.4
12.2
5.7
10.6
12.1
11.4
9.2
7.1
5.7
5.0
5.9
4.3
3.8
7.3
11.3
7.8
2.9
12.1
3.8
10.6
11.5
11.1
8.0
6.1
5.2
4.1
4.3
4.5
3.9
6.9
10.8
7.3
2.9
11.5
3.9
10.8
11.6
11.0
8.3
6.1
5.3
4.3
5.3
4.1
3.9
6.9
10.7
7.4
2.8
11.6
3.9
10.8
11.1
10.3
6.8
7.0
4.8
4.1
4.2
4.9
4.3
6.3
8.7
6.9
2.6
11.1
4.1
6RC
LCO
GCO
SR
BRN
HAM
10.2
11.4
10.7
8.7
8.0
6.7
6.9
7.0
6.1
7.1
10.0
11.4
8.7
1.9
11.4
6.1
10.2
11.6
10.9
8.6
8.0
7.0
6.7
6.7
6.5
7.5
10.1
10.5
8.7
1.8
11.6
6.5
7.9
10.1
9.4
6.7
6.7
4.4
5.1
3.7
5.1
6.2
8.7
10.2
7.0
2.1
10.2
3.7
7.7
11.4
10.0
7.1
3.7
3.2
0.2
0.3
0.4
0.8
1.0
9.8
4.6
4.1
11.4
0.2
9.9
11.4
10.6
9.2
8.7
7.2
6.9
6.5
7.2
8.1
10.1
11.9
9.0
1.8
11.9
6.5
9.1
11.5
10.5
8.7
6.1
6.4
4.7
6.2
3.4
3.7
9.0
11.2
7.5
2.7
11.5
3.4
month NCF117 B210
JAN
11.1
8.8
FEB
10.7
10.6
MAR
10.2
9.8
APR
6.1
6.3
MAY
6.0
6.0
JUN
3.6
5.0
JUL
3.1
4.6
AUG
3.5
4.6
SEP
4.9
5.3
OCT
3.5
5.2
NOV
7.3
8.8
DEC
8.9
10.4
mean
6.6
7.1
std dev
2.9
2.3
max
11.1
10.6
min
3.1
4.6
COL
7.6
9.1
9.2
6.2
7.3
5.2
4.7
3.6
5.6
5.4
8.0
10.0
6.8
1.9
10.0
3.6
LVC2 SC-CH
6.3
10.1
8.5
6.5
3.6
5.1
2.3
3.3
3.3
4.8
9.1
9.6
6.0
2.6
10.1
2.3
10.2
11.0
9.0
6.5
5.3
4.7
3.9
4.5
3.1
4.5
6.5
8.3
6.5
2.5
11.0
3.1
25
Table 2.6 Field Turbidity (NTU) at the LCFRP stations for 2005. The NC State standards are 50 and 25 NTU for freshwater
and tidal saltwater, respectively.
month
JAN
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
mean
std dev
max
min
NAV
HB
BRR
M61
M54
M42
M35
M23
M18
SPD
19
19
20
28
27
11
22
22
10
22
55
17
23
11
55
10
14
12
15
27
21
10
9
17
12
15
10
20
15
5
27
9
11
11
17
26
25
8
10
17
7
11
8
17
14
6
26
7
7
8
20
16
13
7
6
7
6
11
7
11
10
4
20
6
14
8
25
35
11
7
8
7
7
12
4
10
12
9
35
4
7
7
17
23
12
5
11
6
5
7
4
8
9
5
23
4
7
7
10
20
12
4
6
12
5
7
7
7
9
4
20
4
7
8
13
12
7
3
4
6
7
6
5
6
7
3
13
3
17
6
17
11
11
1
2
7
7
7
5
15
9
5
17
1
14
5
11
11
14
5
3
6
6
13
7
10
9
4
14
3
month
JAN
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
mean
std dev
max
min
ANC
SAR
GS
NC403
PB
LRC
ROC
3
7
4
5
4
4
8
4
2
0
3
3
4
2
8
0
4
4
3
5
11
9
5
6
6
1
2
1
5
3
11
1
1
2
2
2
2
8
20
4
11
1
2
0
5
6
20
0
1
2
0
2
1
9
4
3
5
8
11
36
16
8
16
11
4
11
9
36
3
1
5
2
6
2
3
3
2
2
8
2
3
3
2
8
1
3
4
2
9
4
4
17
7
5
3
2
1
5
4
17
1
12
4
1
0
3
4
12
0
BC117 BCRR
11
8
5
9
8
7
12
11
11
9
7
5
9
2
12
5
4
11
9
9
6
16
33
25
19
7
10
7
13
8
33
4
month
JAN
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
mean
std dev
max
min
month
JAN
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
mean
std dev
max
min
NC11
AC
DP
BBT
IC
NCF6
11
18
35
49
12
13
15
19
10
15
7
27
19
12
49
7
8
19
26
43
13
12
15
12
12
18
6
26
18
10
43
6
5
15
26
36
15
8
22
15
10
13
10
28
17
9
36
5
9
12
17
18
11
8
10
5
12
10
3
18
11
5
18
3
11
13
20
28
13
7
13
10
18
18
9
27
16
6
28
7
6
7
13
5
26
5
43
10
22
20
9
10
15
11
43
5
6RC
LCO
GCO
SR
BRN
HAM
4
9
3
8
3
10
4
7
3
3
4
2
5
3
10
2
4
3
2
4
3
5
2
10
2
2
2
1
3
2
10
1
2
0
0
1
1
9
5
11
7
3
2
1
4
4
11
0
1
2
0
1
2
1
5
8
11
21
12
1
5
6
21
0
3
4
3
4
5
5
6
13
3
3
4
2
5
3
13
2
6
5
5
6
5
5
6
9
3
4
3
7
5
2
9
3
month NCF117 B210
JAN
4
3
FEB
6
4
MAR
7
5
APR
4
5
MAY
4
6
JUN
3
4
JUL
2
3
AUG
1
4
SEP
2
2
OCT
2
3
NOV
5
5
DEC
4
3
mean
4
4
std dev
2
1
max
7
6
min
1
2
COL
1
3
3
0
2
1
1
1
0
0
3
1
1
1
3
0
LVC2 SC-CH
3
4
3
3
7
2
5
3
4
4
6
3
4
1
7
2
8
23
16
17
13
7
16
25
8
5
18
13
14
6
25
5
26
Table 2.7 Total Suspended Solids (mg/L) at the LCFRP stations for 2005.
month
JAN
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
mean
std dev
max
min
NAV
HB
BRR
M61
M54
M42
M35
M23
M18
SPD
16
32
23
24
37
9
15
18
19
24
85
16
26.5
19.1
85.0
9.0
11
12
15
22
19
15
12
13
16
11
17
13
14.7
3.2
22.0
11.0
10
10
13
18
30
8
9
20
14
10
14
16
14.3
5.9
30.0
8.0
6
10
18
13
17
11
9
10
8
19
8
13
11.8
4.1
19.0
6.0
10
9
26
35
19
10
11
11
11
14
7
13
14.7
7.8
35.0
7.0
6
11
16
27
15
8
13
9
9
9
7
12
11.8
5.4
27.0
6.0
9
10
15
21
14
9
9
12
8
9
8
14
11.5
3.7
21.0
8.0
6
19
20
16
7
7
9
9
12
9
9
9
11.0
4.5
20.0
6.0
21
15
27
15
14
6
8
8
16
9
8
23
14.2
6.5
27.0
6.0
25
10
21
17
23
11
7
10
11
16
14
26
15.9
6.2
26.0
7.0
month
JAN
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
mean
std dev
max
min
ANC
SAR
GS
NC403
PB
LRC
ROC
BC117
BCRR
2
3
2
3
5
3
6
5
3
2
2
2
3.1
1.4
6.0
1.5
2
2
2
9
10
11
4
8
10
3
3
1
5.3
3.8
11.0
1.0
2
1
2
3
4
24
30
7
17
4
6
2
8.4
9.4
30.0
1.0
2
3
2
3
1
6
4
2
5
5
12
17
12
8
9
13
4
8.0
4.4
17.0
1.5
2
4
5
5
3
2
3
2
1
13
2
5
3.9
3.1
13.0
1.0
2
3
2
14
5
3
6
8
4
5
2
1
4.5
3.5
14.0
1.0
5
29
3
8
9
6
7
11
6
12
6
5
8.9
6.5
29.0
3.0
4
6
3
6
6
12
20
13
12
9
9
3
8.6
4.8
20.0
3.0
7
5
2
1
2.8
1.9
7.0
1.0
month
JAN
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
mean
std dev
max
min
month
JAN
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
mean
std dev
max
min
NC11
AC
DP
IC
NCF6
6
13
23
50
12
14
14
15
7
10
7
19
15.8
11.3
50.0
6.0
5
13
15
50
11
10
12
11
9
13
4
20
14.4
11.5
50.0
4.0
5
10
24
42
17
7
17
11
9
9
6
22
14.9
10.1
42.0
5.0
7
8
17
27
12
5
8
7
11
14
7
18
11.8
6.1
27.0
5.0
8
7
14
8
66
4
23
11
24
25
16
13
18.3
15.9
66.0
4.0
6RC
LCO
GCO
SR
BRN
HAM
2
3
4
12
4
12
3
4
2
2
2
2
4.3
3.5
12.0
1.5
2
3
2
6
2
5
1
5
3
1
1
1
2.6
1.7
6.0
1.0
2
2
2
1
2
14
4
12
4
2
1
1
3.8
4.3
14.0
1.0
3
2
2
1
4
2
22
15
14
13
8
1
7.2
6.8
22.0
1.0
2
2
6
6
3
7
6
18
3
2
2
2
4.9
4.4
18.0
1.5
2
3
2
5
13
4
13
6
3
3
1
2
4.7
4.0
13.0
1.0
month NCF117 B210
JAN
3
2
FEB
1
1
MAR
4
2
APR
3
4
MAY
6
2
JUN
3
3
JUL
2
3
AUG
2
5
SEP
3
2
OCT
4
2
NOV
2
1
DEC
2
1
mean
2.9
2.2
std dev
1.3
1.3
max
6.0
5.0
min
1.0
0.5
COL
LVC2
2
1
2
2
2
3
2
1
1
2
1
1
1.6
0.6
3.0
1.0
2
2
2
2
4
3
3
2
4
3
1
1
2.3
1.1
4.0
1.0
27
Table 2.8 Light Attenuation (k) at the LCFRP boat sampled stations for 2005.
month NAV
HB
BRR
M61
M54
M42
M35
M23
M18
SPD
JAN
3.05
2.79
2.74
2.24
2.46
1.90
1.68
1.49
2.00
1.72
FEB
3.78
2.95
2.41
2.50
2.33
2.03
2.07
1.79
1.38
1.29
MAR
APR
4.06
4.06
3.54
3.74
4.86
3.99
3.62
MAY
JUN
2.93
3.18
3.42
3.07
2.66
2.20
1.80
month NC11
AC
DP
IC
NCF6
BBT
JAN
2.18
1.99
2.63
2.59
2.83
2.77
FEB
2.72
2.67
2.62
2.56
2.77
2.52
MAR
3.42
3.68
3.73
2.79
4.56
2.58
2.36
2.40
2.69
APR
4.45
4.53
3.99
4.53
4.04
3.94
1.21
1.23
1.90
MAY
2.33
3.03
3.34
3.59
6.48
3.45
1.35
0.88
1.45
JUN
2.79
2.62
2.82
4.16
JUL
JUL
AUG
AUG
2.57
2.93
3.05
3.34
4.30
3.56
SEP
2.10
3.40
3.77
4.21
4.33
4.71
OCT
2.20
4.04
3.78
4.31
4.51
3.79
SEP
3.63
2.82
2.81
2.31
2.37
1.61
1.73
1.26
OCT
3.90
3.49
3.16
3.00
2.50
2.08
1.92
1.16
1.03
NOV
10.09
4.76
4.43
4.34
3.72
3.98
3.53
2.33
2.14
2.57
NOV
2.10
2.31
3.84
3.61
5.86
3.33
DEC
3.85
4.07
4.38
4.52
3.50
3.68
2.75
2.41
2.92
2.22
DEC
3.73
3.91
4.06
3.31
5.48
3.69
mean
4.41
3.52
3.36
3.22
3.05
2.68
2.39
1.76
1.75
1.89
mean
2.78
3.19
3.48
3.42
4.48
3.43
std dev 2.18
0.67
0.69
0.84
0.84
0.95
0.75
0.50
0.68
0.52
std dev 0.74
0.75
0.51
0.67
1.08
0.64
max
10.09
4.76
4.43
4.52
4.86
3.99
3.62
2.41
2.92
2.69
max
4.45
4.53
4.06
4.53
6.48
4.71
min
2.93
2.79
2.41
2.24
2.33
1.61
1.68
1.16
0.88
1.26
min
2.10
1.99
2.62
2.56
2.77
2.52
28
Table 2.9 Total Nitrogen concentrations (mg/L) at the LCFRP stations for 2005.
month
NAV
930
780
MAR 1,000
APR
960
MAY 1,370
JUN
1,120
JUL
1,710
AUG 1,750
SEP
1,360
OCT
540
NOV 1,670
DEC
1,260
mean 1,204
std dev
369
max
1,750
min
540
JAN
FEB
month
ANC
1,140
FEB
1,080
MAR
960
APR
1,490
MAY 1,300
JUN
1,660
JUL
1,870
AUG 1,760
SEP
1,520
OCT 1,730
NOV 1,710
DEC
1,760
mean 1,498
std dev
293
max
1,870
min
960
JAN
HB
BRR
M61
M54
M42
M35
M23
M18
SPD
940
1,200
1,020
1,040
1,290
1,130
1,170
1,250
1,640
940
1,330
980
1,161
194
1,640
940
850
510
1,120
1,040
1,300
1,200
1,490
930
910
930
1,430
1,090
1,067
259
1,490
510
990
1,190
1,220
1,010
1,230
1,160
1,300
1,060
1,430
690
1,240
1,380
1,158
191
1,430
690
1,000
1,130
1,150
1,280
1,180
1,260
1,180
2,850
480
670
1,100
1,420
1,225
550
2,850
480
850
1,350
1,110
1,170
970
1,120
880
970
300
550
1,250
1,280
983
295
1,350
300
450
980
860
1,190
930
960
870
1,160
300
480
670
1,120
831
281
1,190
300
470
890
1,060
1,060
700
630
360
880
370
280
1,060
1,440
767
343
1,440
280
410
660
680
830
450
440
560
670
420
230
1,220
870
620
254
1,220
230
390
410
580
620
830
670
580
260
360
250
1,260
830
587
277
1,260
250
SAR
GS
NC403
PB
LRC
ROC
BC117
BCRR
1,170
1,510
1,210
1,140
1,350
1,640
2,860
1,690
1,770
1,080
1,170
1,320
1,493
469
2,860
1,080
640
430
570
940
1,160
1,350
1,870
1,260
1,800
1,070
1,310
1,200
1,133
427
1,870
430
1,030
1,320
1,010
950
940
830
960
1,100
980
850
2,700
2,190
1,490
1,630
1,460
1,170
930
1,358
557
2,700
830
350
640
400
830
710
680
1,370
1,000
1,290
1,250
950
1,110
882
324
1,370
350
790 7,250 460
840 1,250 500
350
680
150
1,130 1,230 750
1,070 11,150 910
930 11,260 1,240
1,690 2,560 2,250
1,550 3,150 1,910
1,430 2,420 1,350
1,360 880
930
1,310 5,030 1,170
1,160 480
950
1,134 3,945 1,048
356 3,754 571
1,690 11,260 2,250
350
480
150
1,480
1,570
890
2,190
1,264
403
2,190
890
month
NC11
3,730
1,420
MAR 1,130
APR
1,240
MAY 1,300
JUN
1,400
JUL
1,900
AUG 1,910
SEP
1,830
OCT 1,010
NOV 1,240
DEC
1,480
mean 1,633
std dev
693
max
3,730
min
1,010
JAN
FEB
month
6RC
440
FEB
550
MAR 1,540
APR
1,230
MAY 1,000
JUN
1,460
JUL
1,280
AUG 1,780
SEP
1,380
OCT
940
NOV 2,430
DEC
850
mean 1,240
std dev
523
max
2,430
min
440
JAN
AC
DP
IC
NCF6
1,020
1,380
1,160
1,230
1,970
1,320
1,450
1,590
2,100
1,430
750
1,500
1,408
356
2,100
800
830
1,430
920
1,190
1,450
1,350
1,250
1,610
2,100
920
1,790
810
1,304
385
2,100
750
970
1,240
900
1,220
1,450
1,430
1,430
1,440
1,740
1,250
1,070
800
1,245
261
1,740
810
850
1,000
980
950
1,290
940
880
1,060
1,360
910
1,040
1,110
1,031
150
1,360
850
LCO
GCO
SR
BRN
HAM
month NCF117 B210
COL
LVC2
720
1,010
880
930
900
1,210
1,010
1,350
1,050
840
900
870
973
163
1,350
720
680
1,140
670
550
1,410
1,030
1,230
1,260
1,220
1,240
1,240
800
1,039
275
1,410
550
1,090
280
420
580
780
1,060
1,640
1,590
1,670
1,350
1,120
940
1,043
449
1,670
280
620
830
3,190
750
720
530
1,170
820
880
730
810
1,510
1,047
692
3,190
530
460
900
820
920
820
1,020
990
1,210
870
610
750
890
855
185
1,210
460
980
FEB
1,270
MAR
990
APR
1,020
MAY 1,070
JUN
950
JUL
1,190
AUG
920
SEP
1,240
OCT 1,210
NOV 1,380
DEC
1,350
mean 1,131
std dev
155
max
1,380
min
920
940
660
710
1,110
1,160
1,370
1,530
930
1,630
1,450
980
1,590
1,172
324
1,630
660
900
400
550
490
940
670
1,480
1,550
1,380
790
870
1,340
947
383
1,550
400
JAN
620
810
640
850
940
870
1,330
650
1,420
1,500
1,010
980
968
289
1,500
620
29
Table 2.10 Nitrate-Nitrite concentrations (mg/L) at the LCFRP stations for 2005.
month
NAV
HB
BRR
M61
M54
M42
M35
M23
M18
SPD
month
NC11
AC
DP
IC
NCF6
BBT
JAN
min
430
130
580
250
610
410
590
770
290
70
360
140
386
211
770
70
420
710
580
350
570
440
420
320
330
100
120
90
371
189
710
90
480
30
620
360
560
440
320
40
350
90
310
110
309
193
620
30
390
520
600
230
450
370
270
170
260
130
170
450
334
145
600
130
430
320
490
240
440
380
220
610
200
110
70
530
337
164
610
70
290
360
560
290
330
350
180
460
110
80
130
110
271
146
560
80
190
440
440
310
320
240
30
460
70
60
60
280
242
153
460
30
140
410
110
280
240
110
80
130
15
50
310
460
195
138
460
15
20
110
40
20
50
30
50
60
15
15
430
170
84
113
430
15
90
5
100
70
80
110
70
30
80
60
560
130
115
138
560
5
620
1,020
MAR
420
APR
450
MAY
800
JUN
720
JUL
800
AUG
650
SEP
760
OCT
260
NOV
310
DEC
450
mean
605
std dev
219
max
1,020
min
260
570
950
560
460
830
580
700
610
560
120
240
380
547
221
950
120
450
980
510
440
790
470
40
680
470
130
160
110
436
277
980
40
440
810
300
470
740
540
590
510
430
130
140
50
429
228
810
50
380
520
380
100
270
150
180
270
290
70
60
40
226
145
520
40
533
714
597
407
616
555
404
288
553
398
411
536
501
115
714
288
month
ANC
SAR
GS
NC403
PB
LRC
ROC
BC117
BCRR
LCO
GCO
SR
BRN
HAM
JAN
40
150
5
60
40
60
50
30
30
15
30
130
53
42
150
5
520
950
600
80
250
200
1,510
60
180
50
15
290
392
428
1,510
15
5
5
5
5
50
5
50
15
30
15
15
80
23
23
80
5
410
740
520
90
290
130
280
780
5
30
1,130
90
15
40
110
15
180
234
339
1,130
5
40
330
400
190
130
40
200
70
30
40
60
320
154
127
400
30
220
420
350
120
390
130
380
150
30
50
240
130
218
132
420
30
6,320
950
130
450
9,750
9,950
1,250
1,800
1,350
40
3,300
200
2,958
3,509
9,950
40
5
180
150
40
90
80
760
510
140
90
50
60
180
215
760
5
240
740
570
150
180
160
80
90
70
15
60
30
199
216
740
15
210
720
340
5
100
5
110
15
150
70
170
60
163
192
720
5
590
30
20
5
90
5
50
15
40
15
15
50
77
156
590
5
130
490
1,470
70
120
5
100
30
40
30
60
530
256
403
1,470
5
50
330
400
50
60
100
60
90
30
15
15
15
101
122
400
15
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
mean
std dev
max
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
mean
std dev
max
min
30
30
50
980
349
324
980
30
JAN
FEB
month
6RC
30
280
MAR 1,130
APR
490
MAY
330
JUN
440
JUL
440
AUG 1,030
SEP
70
OCT
100
NOV
420
DEC
60
mean
402
std dev
343
max
1,130
min
30
JAN
FEB
month NCF117 B210
COL
LVC2
390
730
490
140
180
90
260
30
80
15
120
320
237
205
730
15
5
5
5
5
20
5
40
40
15
15
15
520
58
140
520
5
200
90
30
5
280
40
450
150
220
15
30
80
133
129
450
5
JAN
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
mean
std dev
max
min
160
500
250
110
180
170
120
40
70
50
80
90
152
120
500
40
30
Table 2.11 Ammonium concentrations (mg/L) at the LCFRP stations for 2005.
month
NAV
HB
BRR
M61
M54
M42
M35
M23
M18
SPD
month
NC11
AC
DP
IC
NCF6
BBT
JAN
80
10
10
10
20
70
90
80
20
40
100
70
50
33
100
10
100
10
10
20
10
10
50
80
20
30
100
70
43
34
100
10
100
10
40
30
20
10
60
50
30
20
110
100
48
35
110
10
180
30
10
190
10
20
40
40
10
20
160
110
68
68
190
10
90
10
10
50
30
50
20
30
10
20
140
120
48
43
140
10
50
40
10
50
30
10
20
30
10
10
100
120
40
35
120
10
10
40
10
40
50
60
10
20
10
10
50
60
31
20
60
10
10
10
10
10
50
80
20
20
10
10
40
40
26
21
80
10
10
210
10
10
40
60
40
50
10
20
20
30
43
53
210
10
JAN
min
10
130
10
10
10
40
60
90
30
50
60
50
46
35
130
10
10
10
30
20
10
40
90
140
240
210
40
70
76
76
240
10
10
20
10
10
10
110
140
120
120
100
240
90
82
69
240
10
10
20
10
30
20
10
120
70
100
70
120
70
54
41
120
10
70
40
10
10
30
60
20
20
30
20
40
30
32
18
70
10
53
52
min
90
130
10
20
20
50
80
110
40
30
90
70
62
37
130
10
month
ANC
SAR
GS
NC403
PB
LRC
ROC
BC117
BCRR
month
6RC
LCO
GCO
SR
BRN
HAM
JAN
10
10
10
10
30
50
260
100
90
220
40
40
73
81
260
10
30
40
10
10
20
30
260
50
80
40
40
20
53
65
260
10
10
20
10
10
30
10
210
20
80
40
20
20
40
55
210
10
10
20
10
10
20
10
20
10
140
30
20
340
30
220
320
20
80
103
118
340
10
10
160
10
10
30
10
80
40
50
150
40
60
54
50
160
10
10
10
10
10
30
60
160
50
80
130
40
30
52
47
160
10
40
110
10
30
10
70
140
90
70
100
60
50
65
38
140
10
10
120
10
70
10
130
80
80
30
90
20
30
57
42
130
10
JAN
50
10
30
10
30
10
60
40
20
40
50
60
34
18
60
10
70
100
10
10
20
90
40
20
30
20
20
20
38
30
100
10
40
120
10
10
20
10
130
60
40
40
30
20
44
39
130
10
40
150
10
10
30
60
280
110
140
90
20
10
79
78
280
10
30
10
640
10
40
120
50
40
30
30
40
140
98
168
640
10
10
130
10
10
10
60
80
60
30
40
30
30
42
35
130
10
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
mean
std dev
max
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
mean
std dev
max
min
90
280
60
30
59
82
280
10
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
mean
std dev
max
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
mean
std dev
max
min
53
130
110
83
24
113
134
52
74
80
35
134
24
month NCF117 B210
COL
LVC2
10
20
10
10
10
100
50
40
30
30
30
30
31
24
100
10
10
30
10
10
20
60
90
120
120
40
20
20
46
40
120
10
150
10
100
10
10
60
340
90
30
130
100
110
95
87
340
10
JAN
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
mean
std dev
max
min
10
20
10
10
30
10
50
20
40
30
10
20
22
13
50
10
31
Table 2.12 Total Kjeldahl Nitrogen concentrations (mg/L) at the LCFRP stations for 2005.
month
NAV
500
650
MAR
420
APR
710
MAY
760
JUN
710
JUL
1,120
AUG
980
SEP
1,070
OCT
470
NOV 1,310
DEC
1,120
mean
818
std dev
281
max
1,310
min
420
JAN
FEB
month
ANC
1,100
FEB
930
MAR
960
APR
1,430
MAY 1,260
JUN
1,600
JUL
1,820
AUG 1,730
SEP
1,490
OCT 1,730
NOV 1,680
DEC
1,630
mean 1,447
std dev
299
max
1,820
min
930
JAN
HB
BRR
M61
M54
M42
M35
M23
M18
SPD
month
520
490
440
690
720
690
750
930
1,310
840
1,210
890
790
257
1,310
440
370
480
500
680
740
760
1,170
890
560
840
1,120
980
758
244
1,170
370
600
670
620
780
780
790
1,030
890
1,170
560
1,070
930
824
189
1,170
560
570
810
660
1,040
740
880
960
2,240
280
560
1,030
890
888
460
2,240
280
560
990
550
880
640
770
700
510
190
470
1,120
1,170
713
276
1,170
190
260
540
420
880
610
720
840
700
230
420
610
840
589
212
880
230
330
480
950
780
460
520
280
750
370
230
750
980
573
249
980
230
390
550
640
810
400
410
510
610
420
230
790
700
538
170
810
230
300
410
480
550
750
560
510
230
280
190
700
700
472
184
750
190
3,110
400
MAR
710
APR
790
MAY
500
JUN
680
JUL
1,100
AUG 1,260
SEP
1,070
OCT
750
NOV
930
DEC
1,030
mean 1,028
std dev
673
max
3,110
min
400
SAR
GS
NC403
PB
LRC
ROC
BC117
BCRR
month
650
560
610
1,060
1,100
1,440
1,350
1,630
1,590
1,030
1,170
1,030
1,102
348
1,630
560
640
430
570
940
1,110
1,350
1,820
1,260
1,770
1,070
1,310
1,120
1,116
415
1,820
430
620
580
490
860
650
700
680
320
980
820
1,570
2,100
1,490
1,590
1,350
1,170
750
1,127
486
2,100
320
310
310
100
640
580
640
1,170
930
1,260
1,210
890
790
736
361
1,260
100
570
420
100
1,010
680
800
1,310
1,400
1,400
1,310
1,070
1,030
925
400
1,400
100
930
300
550
780
1,400
1,310
1,310
1,350
1,070
840
1,730
280
988
438
1,730
280
460
320
100
710
820
1,160
1,490
1,400
1,210
840
1,120
890
877
410
1,490
100
410
FEB
270
MAR
410
APR
740
MAY
670
JUN
1,020
JUL
840
AUG
750
SEP
1,310
OCT
840
NOV 2,010
DEC
790
mean
838
std dev
444
max
2,010
min
270
1,450
1,540
840
1,210
916
369
1,540
490
NC11
JAN
FEB
JAN
6RC
AC
DP
IC
NCF6
450
430
600
770
1,140
740
750
980
1,540
1,310
510
1,120
862
342
1,540
430
380
450
410
750
660
880
1,210
930
1,630
790
1,630
700
868
408
1,630
380
530
430
600
750
710
890
840
930
1,310
1,120
930
750
816
236
1,310
430
470
480
600
850
1,020
790
700
790
1,070
840
980
1,070
805
202
1,070
470
LCO
GCO
SR
BRN
HAM
month NCF117 B210
COL
LVC2
480
270
310
780
720
1,050
930
1,260
980
840
840
840
775
281
1,260
270
470
420
330
550
1,310
1,030
1,120
1,260
1,070
1,170
1,070
740
878
339
1,310
330
500
250
400
580
690
1,060
1,590
1,590
1,630
1,350
1,120
890
971
473
1,630
250
490
340
1,720
680
600
530
1,070
790
840
700
750
980
791
342
1,720
340
410
570
420
870
760
920
930
1,120
840
610
750
890
758
207
1,120
410
590
FEB
540
MAR
500
APR
880
MAY
890
JUN
860
JUL
930
AUG
890
SEP
1,160
OCT 1,210
NOV 1,260
DEC
1,030
mean
895
std dev
241
max
1,260
min
500
940
660
710
1,110
1,140
1,370
1,490
890
1,630
1,450
980
1,070
1,120
297
1,630
660
700
310
520
490
660
630
1,030
1,400
1,160
790
840
1,260
816
320
1,400
310
JAN
460
310
390
740
760
700
1,210
610
1,350
1,450
930
890
817
352
1,450
310
32
Table 2.14 Orthophosphate concentrations (mg/L) at the LCFRP stations for 2005.
month
NAV
HB
BRR
M61
M54
M42
M35
M23
M18
SPD
month
NC11
AC
DP
IC
NCF6
BBT
JAN
30
50
30
40
50
70
70
100
30
40
50
50
51
20
100
30
30
40
30
40
30
70
50
100
50
50
50
40
48
19
100
30
30
30
30
40
40
60
50
80
50
30
40
40
43
14
80
30
30
30
40
60
40
50
30
70
30
40
50
40
43
12
70
30
20
30
40
10
30
40
30
60
20
30
40
40
33
12
60
10
10
10
10
40
20
20
10
50
20
30
20
40
23
13
50
10
5
0
0
5
10
10
20
30
10
20
20
30
13
10
30
0
5
0
0
5
10
20
10
30
10
10
20
30
13
10
30
0
10
0
0
5
10
10
10
20
10
20
10
10
10
6
20
0
JAN
min
30
40
30
40
50
70
100
80
50
50
60
40
53
20
100
30
min
70
50
30
40
50
80
90
70
90
110
140
100
77
30
140
30
70
50
50
40
80
60
80
70
110
120
110
100
78
25
120
40
30
50
50
40
40
60
100
90
70
90
110
90
68
26
110
30
30
40
30
40
40
70
90
70
80
90
70
60
59
21
90
30
30
30
20
30
40
40
70
70
40
40
10
30
38
17
70
10
37
45
31
39
57
58
62
51
78
80
30
49
51
16
80
30
month
ANC
SAR
GS
NC403
PB
LRC
ROC
BC117
BCRR
month
6RC
LCO
GCO
SR
BRN
HAM
JAN
70
50
50
100
20
180
100
170
10
110
110
40
84
52
180
10
30
10
20
50
70
110
60
60
10
70
40
10
45
30
110
10
20
10
10
30
40
40
40
60
10
70
40
20
33
19
70
10
100
60
30
140
20
40
30
20
50
20
20
100
70
40
90
30
10
43
28
100
10
5
10
0
10
10
10
30
10
10
20
10
10
11
7
30
0
50
20
40
40
30
70
110
100
10
100
20
20
51
34
110
10
1,950
620
620
160
530
1,420
1,390
1,100
170
110
920
1,020
834
549
1,950
110
20
10
10
20
10
30
30
50
10
20
60
10
23
16
60
10
JAN
20
10
10
20
20
40
50
40
10
60
20
10
26
17
60
10
30
10
10
10
20
20
40
30
10
30
20
10
20
10
40
10
190
120
90
140
70
220
120
120
10
150
160
70
122
55
220
10
10
0
10
10
10
10
10
30
10
20
20
10
13
7
30
0
20
10
20
20
20
40
50
30
10
50
20
20
26
13
50
10
30
10
20
40
40
50
80
70
10
100
50
20
43
27
100
10
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
mean
std dev
max
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
mean
std dev
max
min
10
50
80
30
58
40
140
10
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
mean
std dev
max
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
mean
std dev
max
min
month NCF117 B210
COL
LVC2
20
20
20
40
30
40
70
60
30
50
40
20
37
16
70
20
5
0
0
10
10
10
10
20
40
20
10
0
11
11
40
0
10
0
10
0
10
0
20
10
10
10
0
20
8
7
20
0
JAN
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
mean
std dev
max
min
20
10
10
20
20
30
40
50
40
30
20
10
25
13
50
10
33
Table 2.13 Total Phosphorous concentrations (mg/L) at the LCFRP stations for 2005.
month
NAV
HB
BRR
M61
M54
M42
M35
M23
M18
SPD
month
NC11
AC
DP
IC
NCF6
JAN
70
130
80
110
110
120
120
130
100
70
70
60
98
25
130
60
70
150
80
120
100
110
130
140
100
70
70
80
102
27
150
70
60
70
100
100
100
100
110
110
240
50
40
60
95
50
240
40
70
70
140
150
80
60
80
120
80
60
50
60
85
32
150
50
20
80
100
10
50
70
90
90
60
40
50
50
59
27
100
10
10
50
60
110
60
50
70
90
50
30
20
50
54
27
110
10
5
5
30
5
5
20
40
70
30
10
10
30
22
19
70
5
5
5
30
5
10
20
40
50
40
10
10
30
21
15
50
5
20
130
30
5
5
30
60
90
40
30
10
10
38
36
130
5
JAN
min
80
140
90
70
160
120
120
120
100
120
200
110
119
34
200
70
min
100
140
100
110
130
130
160
610
160
160
220
170
183
133
610
100
80
100
100
140
170
110
180
130
190
150
210
180
145
40
210
80
60
100
110
80
140
100
180
120
160
120
170
160
125
36
180
60
70
90
80
90
150
110
160
90
150
130
100
100
110
29
160
70
50
80
70
60
160
70
110
100
150
80
10
80
85
39
160
10
month
ANC
SAR
GS
NC403
PB
LRC
ROC
BC117
BCRR
month
6RC
LCO
GCO
SR
BRN
HAM
JAN
100
100
70
120
20
240
230
220
10
110
200
40
122
79
240
10
80
60
60
120
170
180
180
160
10
160
120
20
110
60
180
10
50
50
40
120
140
480
790
180
10
180
110
10
180
220
790
10
160
120
90
220
110
160
100
110
130
100
160
680
530
40
380
160
40
216
195
680
40
5
20
30
20
40
30
60
80
10
120
10
10
36
33
120
5
90
50
50
100
150
160
230
140
10
200
50
30
105
68
230
10
1,950
780
690
220
530
2,130
1,390
1,100
170
210
950
1,020
928
617
2,130
170
80
50
40
130
70
160
190
120
10
110
150
40
96
54
190
10
JAN
20
40
40
140
80
140
160
100
10
120
70
100
85
48
160
10
30
30
20
40
60
70
110
60
10
60
10
30
44
28
110
10
190
150
170
170
230
850
460
270
10
240
170
90
250
208
850
10
50
20
20
30
80
70
290
140
10
130
120
10
81
78
290
10
60
40
60
80
150
80
140
90
10
100
20
30
72
42
150
10
90
50
60
120
170
140
250
130
20
230
70
40
114
71
250
20
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
mean
std dev
max
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
mean
std dev
max
min
10
750
180
370
223
209
750
10
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
mean
std dev
max
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
mean
std dev
max
min
month NCF117 B210
COL
LVC2
40
40
60
60
80
80
150
120
90
70
40
30
72
34
150
30
5
100
20
10
400
30
70
40
60
30
10
100
73
104
400
5
20
20
20
10
50
10
120
140
70
40
10
10
43
43
140
10
JAN
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
mean
std dev
max
min
30
30
30
50
80
90
170
90
100
90
40
10
68
43
170
10
34
Table 2.15 Aluminum concentrations (mg/L) at the LCFRP stations for 2005.
Table 2.16 Arsenic concentrations (mg/L) at the LCFRP stations for 2005.
There is no NC State standard.
The NC State standard is 50 mg/L for freshwater and saltwater.
month
NAV
M54
M35
M23
M18
NC11
DP
month
NAV
M54
M35
M23
M18
NC11
DP
FEB
536
262
299
181
143
1,560
1,060
FEB
0
0
14
24
34
0
0
APR
1,250
1,420
1,600
1,050
739
3,320
1,540
APR
0
0
0
0
0
0
0
JUN
400
447
272
222
124
629
428
JUN
0
0
15
22
22
0
0
AUG
509
251
170
187
169
360
478
AUG
0
0
0
0
0
0
0
OCT
334
245
74
683
0
84
149
OCT
0
0
0
0
0
0
0
DEC
555
439
403
285
143
459
769
DEC
0
0
0
0
0
0
0
mean
597
511
470
435
220
1069
737
mean
0
0
5
8
9
0
0
std dev
302
416
516
325
239
1107
458
std dev
0
0
7
11
14
0
0
max
1250
1420
1600
1050
739
3320
1540
max
0
0
15
24
34
0
0
min
334
245
74
181
0
84
149
min
0
0
0
0
0
0
0
month
SAR
LRC
6RC
GCO
COL
LVC2
month
SAR
LRC
6RC
GCO
COL
LVC2
FEB
161
302
466
363
155
58
738
107
FEB
0
0
0
0
0
0
0
0
APR
307
297
661
475
479
105
987
377
APR
0
0
0
0
0
0
0
0
JUN
341
124
218
482
521
190
1,000
389
JUN
0
0
0
0
0
0
0
0
AUG
308
55
288
398
132
197
901
413
AUG
0
0
0
0
0
0
0
0
OCT
551
339
787
191
30
531
1,010
271
OCT
0
0
0
0
0
0
0
0
DEC
129
44
76
117
68
405
566
119
DEC
0
0
0
0
0
0
0
0
mean
300
194
416
338
231
248
867
279
mean
0
0
0
0
0
0
0
0
std dev
137
122
249
138
195
167
164
126
std dev
0
0
0
0
0
0
0
0
max
551
339
787
482
521
531
1010
413
max
0
0
0
0
0
0
0
0
min
129
44
76
117
30
58
566
107
min
0
0
0
0
0
0
0
0
BC117 NCF 117
BC117 NCF 117
35
Table 2.17 Cadmium concentrations (mg/L) at the LCFRP stations for 2005.
Table 2.18 Chromium concentrations (mg/L) at the LCFRP stations for 2005.
The NC State standard is 2 and 5 mg/L for freshwater and saltwater, respectively.
The NC State standard is 50 and 20 mg/L for freshwater and saltwater, respectively.
month
NAV
M54
M35
M23
M18
NC11
DP
month
NAV
M54
M35
M23
M18
NC11
DP
FEB
0
0
0
0
0
0
0
FEB
0
0
0
0
0
0
0
APR
0
0
0
0
0
0
0
APR
0
0
0
0
0
0
0
JUN
0
0
0
0
0
0
0
JUN
0
0
0
0
0
0
0
AUG
0
0
0
0
0
0
0
AUG
0
0
0
0
0
0
0
OCT
0
0
0
0
0
0
0
OCT
0
0
0
0
0
0
0
DEC
0
0
0
0
0
0
0
DEC
0
0
0
0
0
0
0
mean
0
0
0
0
0
0
0
mean
0
0
0
0
0
0
0
std dev
0
0
0
0
0
0
0
std dev
0
0
0
0
0
0
0
max
0
0
0
0
0
0
0
max
0
0
0
0
0
0
0
min
0
0
0
0
0
0
0
min
0
0
0
0
0
0
0
month
SAR
LRC
6RC
GCO
COL
LVC2
month
SAR
LRC
6RC
GCO
COL
LVC2
FEB
0
0
0
0
0
0
0
0
FEB
0
0
0
0
0
0
0
0
APR
0
0
0
0
0
0
0
0
APR
0
0
0
0
0
0
0
0
JUN
0
0
0
0
0
0
0
0
JUN
0
0
0
0
0
0
0
0
AUG
0
0
0
0
0
0
0
0
AUG
0
0
0
0
0
0
0
0
OCT
0
0
0
0
0
0
0
0
OCT
0
0
0
0
0
0
0
0
DEC
0
0
0
0
0
0
0
0
DEC
0
0
0
0
0
0
0
0
mean
0
0
0
0
0
0
0
0
mean
0
0
0
0
0
0
0
0
std dev
0
0
0
0
0
0
0
0
std dev
0
0
0
0
0
0
0
0
max
0
0
0
0
0
0
0
0
max
0
0
0
0
0
0
0
0
min
0
0
0
0
0
0
0
0
min
0
0
0
0
0
0
0
0
BC117 NCF 117
BC117 NCF 117
36
Table 2.19 Copper concentrations (mg/L) at the LCFRP stations for 2005.
Table 2.20 Iron concentrations (mg/L) at the LCFRP stations for 2005.
The NC State standard is 7 and 3 mg/L for freshwater and saltwater, respectively.
The NC State standard is 1,000 mg/L for freshwater with no standard for saltwater.
month
NAV
M54
M35
M23
M18
NC11
DP
month
NAV
M54
M35
M23
M18
NC11
DP
FEB
2
5
6
7
9
2
2
FEB
1,920
389
315
410
365
1,020
1,030
APR
3
5
8
4
5
5
4
APR
2,340
1,950
940
510
445
2,620
2,280
JUN
0
4
7
9
9
2
0
JUN
1,090
468
310
352
382
1,190
893
AUG
0
0
0
0
0
0
0
AUG
687
455
258
294
150
696
692
OCT
0
0
0
0
0
0
0
OCT
817
534
1,550
329
85
416
803
DEC
0
7
0
71
0
8
0
DEC
817
636
495
388
309
810
941
mean
1
4
4
15
4
3
1
mean
1,279
739
645
381
289
1,125
1,107
std dev
1
3
4
25
4
3
2
std dev
626
547
465
69
129
711
535
max
3
7
8
71
9
8
4
max
2,340
1,950
1,550
510
445
2,620
2,280
min
0
0
0
0
0
0
0
min
687
389
258
294
85
416
692
month
SAR
LRC
6RC
GCO
COL
LVC2
month
SAR
LRC
6RC
GCO
COL
LVC2
FEB
0
0
4
0
0
0
0
0
FEB
466
412
755
386
368
123
420
436
APR
0
0
2
0
0
0
0
0
APR
1,230
942
1,160
665
1,020
348
690
712
JUN
0
0
6
0
0
0
0
0
JUN
1,850
1,460
763
884
1,680
3,660
1,310
933
AUG
0
0
0
0
0
0
0
0
AUG
1,460
1,920
627
1,060
1,600
1,750
1,680
1,390
OCT
0
0
0
0
0
0
0
0
OCT
1,020
1,250
785
1,050
801
757
80
1,240
DEC
0
0
0
0
0
0
0
0
DEC
237
602
593
305
171
453
366
499
mean
0
0
2
0
0
0
0
0
mean
1,044
1,098
781
725
940
1,182
758
868
std dev
0
0
2
0
0
0
0
0
std dev
554
512
184
299
567
1,224
561
356
max
0
0
6
0
0
0
0
0
max
1,850
1,920
1,160
1,060
1,680
3,660
1,680
1,390
min
0
0
0
0
0
0
0
0
min
237
412
593
305
171
123
80
436
BC117 NCF 117
BC117 NCF 117
37
Table 2.21 Lead concentrations (mg/L) at the LCFRP stations for 2005.
Table 2.22 Mercury concentrations (mg/L) at the LCFRP stations for 2005.
The NC State standard is 25 mg/L for freshwater and saltwater.
The NC State standard is 0.012 and 0.025 mg/L for freshwater and saltwater,
respectively.
month
NAV
M54
M35
M23
M18
NC11
DP
month
NAV
M54
M35
M23
M18
NC11
DP
FEB
0
0
0
0
0
0
0
FEB
0
0
0
0
0
0
0
APR
0
0
0
0
0
0
0
APR
0
0
0
0
0
0
0
JUN
0
0
0
0
0
0
0
JUN
0
0
0
0
0
0
0
AUG
0
0
0
0
0
0
0
AUG
0
0
0
0
0
0
0
OCT
0
0
0
0
0
0
0
OCT
0
0
0
0
0
0
0
DEC
0
0
0
0
0
0
0
DEC
0
0
0
0
0
0
0
mean
0
0
0
0
0
0
0
mean
0
0
0
0
0
0
0
std dev
0
0
0
0
0
0
0
std dev
0
0
0
0
0
0
0
max
0
0
0
0
0
0
0
max
0
0
0
0
0
0
0
min
0
0
0
0
0
0
0
min
0
0
0
0
0
0
0
month
SAR
LRC
6RC
GCO
COL
LVC2
month
SAR
LRC
6RC
GCO
COL
LVC2
FEB
0
0
0
0
0
0
0
0
FEB
0
0
0
0
0
0
0
0
APR
0
0
0
0
0
0
0
0
APR
0
0
0
0
0
0
0
0
JUN
0
0
0
0
0
0
0
0
JUN
0
0
0
0
0
0
0
0
AUG
0
0
0
0
0
0
0
0
AUG
0
0
0
0
0
0
0
0
OCT
0
0
0
0
0
0
0
0
OCT
0
0
0
0
0
0
0
0
DEC
0
0
0
0
0
0
0
0
DEC
0
0
0
0
0
0
0
0
mean
0
0
0
0
0
0
0
0
mean
0
0
0
0
0
0
0
0
std dev
0
0
0
0
0
0
0
0
std dev
0
0
0
0
0
0
0
0
max
0
0
0
0
0
0
0
0
max
0
0
0
0
0
0
0
0
min
0
0
0
0
0
0
0
0
min
0
0
0
0
0
0
0
0
BC117 NCF 117
BC117 NCF 117
38
Table 2.23 Nickel concentrations (mg/L) at the LCFRP stations for 2005.
Table 2.24 Zinc concentrations (mg/L) at the LCFRP stations for 2005.
The NC State standard is 88 and 8.2 mg/L for freshwater and saltwater, respectively.
The NC State standard is 50 and 86 mg/L for freshwater and saltwater, respectively.
month
NAV
M54
M35
M23
M18
NC11
DP
month
NAV
M54
M35
M23
M18
NC11
DP
FEB
0
0
10
15
24
0
0
FEB
0
0
0
0
0
0
16
APR
0
0
0
0
0
0
0
APR
11
11
17
0
0
0
0
JUN
0
0
0
13
16
0
0
JUN
0
0
0
0
0
0
0
AUG
0
0
0
0
0
0
0
AUG
0
0
0
0
0
0
0
OCT
0
0
0
0
0
0
0
OCT
0
0
0
0
0
0
0
DEC
0
0
0
13
0
0
0
DEC
15
56
0
13
0
0
0
mean
0
0
2
7
7
0
0
mean
4
11
3
2
0
0
3
std dev
0
0
4
7
10
0
0
std dev
6
20
6
5
0
0
6
max
0
0
10
15
24
0
0
max
15
56
17
13
0
0
16
min
0
0
0
0
0
0
0
min
0
0
0
0
0
0
0
month
SAR
LRC
6RC
GCO
COL
LVC2
month
SAR
LRC
6RC
GCO
COL
LVC2
FEB
0
0
0
0
0
0
0
0
FEB
0
0
17
0
0
0
0
0
APR
0
0
0
0
0
0
0
0
APR
0
0
0
0
0
0
0
0
JUN
0
0
0
0
0
0
0
0
JUN
0
0
28
0
0
0
0
0
AUG
0
0
0
0
0
0
0
0
AUG
0
0
33
0
0
0
0
0
OCT
0
0
0
0
0
0
0
0
OCT
0
0
0
0
0
0
0
0
DEC
0
0
0
0
0
0
0
0
DEC
0
0
0
0
0
0
0
0
mean
0
0
0
0
0
0
0
0
mean
0
0
13
0
0
0
0
0
std dev
0
0
0
0
0
0
0
0
std dev
0
0
14
0
0
0
0
0
max
0
0
0
0
0
0
0
0
max
0
0
33
0
0
0
0
0
min
0
0
0
0
0
0
0
0
min
0
0
0
0
0
0
0
0
BC117 NCF 117
BC117 NCF 117
39
Table 2.25 Chlorophyll a concentrations (mg/L) at the LCFRP stations for 2005. The NC State standard is 40 mg/L.
month
NAV
HB
BRR
M61
M54
M42
M35
M23
M18
SPD
month
NC11
AC
DP
BBT
IC
NCF6
JAN
1.6
4.0
4.7
1.4
1.1
4.1
9.2
3.0
6.9
3.5
0.9
0.9
3.4
2.5
9.2
0.9
1.5
2.3
5.0
1.5
1.2
10.7
13.5
4.3
9.7
2.8
1.1
1.1
4.6
4.1
13.5
1.1
2.1
4.6
4.5
1.3
4.4
13.5
16.6
1.4
7.9
2.6
1.0
0.7
5.1
4.9
16.6
0.7
2.4
6.4
4.6
1.7
1.4
7.0
16.5
3.0
13.0
2.9
1.1
0.7
5.1
4.8
16.5
0.7
1.8
8.2
5.0
1.2
1.7
12.8
31.9
2.0
16.0
2.2
1.3
0.8
7.1
8.9
31.9
0.8
1.5
6.7
8.5
1.3
4.5
20.3
18.3
2.8
11.5
3.6
1.6
1.2
6.8
6.4
20.3
1.2
2.6
15.3
9.7
2.5
0.9
8.1
8.1
2.5
10.3
4.3
3.8
2.1
5.9
4.2
15.3
0.9
4.8
9.7
5.7
2.2
4.8
4.0
4.9
2.4
9.7
3.6
3.9
3.1
4.9
2.4
9.7
2.2
3.0
5.4
11.8
2.6
2.2
5.7
8.2
3.3
12.4
2.9
1.8
2.6
5.2
3.6
12.4
1.8
JAN
min
1.6
4.0
5.3
1.4
0.7
3.7
1.4
2.2
6.2
3.4
2.7
1.1
2.8
1.7
6.2
0.7
min
1.4
2.8
4.8
1.9
2.8
6.9
8.3
4.9
12.9
9.1
3.3
1.9
5.1
3.4
12.9
1.4
1.1
3.1
4.4
1.6
2.0
10.4
3.6
2.8
7.5
8.1
3.0
1.7
4.1
2.8
10.4
1.1
1.0
3.0
4.3
1.6
2.1
15.0
6.9
1.6
2.6
1.9
1.7
1.8
3.6
3.8
15.0
1.0
0.9
1.6
2.5
0.7
1.0
4.4
1.3
0.9
2.6
2.6
0.3
1.0
1.7
1.1
4.4
0.3
0.5
1.9
2.4
1.2
1.1
4.7
2.1
2.0
1.8
1.9
0.9
1.2
1.8
1.0
4.7
0.5
0.5
1.1
0.6
0.3
2.2
1.4
3.2
4.4
5.2
1.9
0.6
0.6
1.8
1.6
5.2
0.3
month
ANC
SAR
GS
NC403
PB
LRC
ROC
BC117
BCRR
month
6RC
LCO
GCO
SR
BRN
HAM
JAN
0.6
1.9
2.0
0.9
0.5
3.8
3.5
8.6
14.7
1.1
0.9
1.2
3.3
4.1
14.7
0.5
0.3
0.7
0.6
1.0
0.5
1.2
0.4
1.0
1.3
0.7
0.4
0.5
0.7
0.3
1.3
0.3
1.1
4.2
1.2
1.0
0.5
15.8
25.9
5.6
34.3
1.5
3.5
1.8
8.0
10.8
34.3
0.5
0.9
9.0
0.9
0.9
0.4
8.5
8.6
1.8
4.1
9.3
45.3
5.5
65.0
25.4
2.2
18.6
3.1
16.5
19.0
65.0
1.8
0.6
2.7
0.6
0.5
0.3
1.6
0.3
0.8
1.3
2.9
1.1
1.7
1.2
0.8
2.9
0.3
0.4
1.1
2.3
0.7
0.4
0.7
0.9
2.1
0.9
1.0
0.7
0.6
1.0
0.6
2.3
0.4
2.5
3.0
1.7
0.9
1.1
2.0
2.0
1.4
0.9
0.6
1.0
1.2
1.5
0.7
3.0
0.6
3.4
1.9
1.0
0.7
0.9
11.4
22.6
148.5
36.3
0.7
3.5
0.7
19.3
40.4
148.5
0.7
JAN
0.3
0.7
0.4
0.7
0.2
1.1
0.4
0.3
0.5
0.5
0.4
0.7
0.5
0.2
1.1
0.2
0.7
0.6
0.3
0.5
0.1
0.7
0.7
0.3
0.3
0.3
0.2
0.6
0.4
0.2
0.7
0.1
0.6
0.7
0.5
0.2
0.3
2.4
12.7
2.7
0.7
0.6
0.4
1.2
1.9
3.3
12.7
0.2
1.4
7.2
0.8
0.3
0.7
1.9
14.2
4.3
22.2
15.7
5.7
2.5
6.4
6.9
22.2
0.3
0.8
1.3
0.5
0.8
0.5
1.3
0.8
1.9
0.5
2.7
0.3
0.4
1.0
0.7
2.7
0.3
0.3
3.6
0.5
0.7
0.6
1.0
1.2
1.1
0.7
0.5
0.2
0.6
0.9
0.9
3.6
0.2
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
mean
std dev
max
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
mean
std dev
max
min
9.2
2.0
2.9
7.8
3.8
3.5
9.2
0.4
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
mean
std dev
max
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
mean
std dev
max
min
month NCF117 B210
COL
LVC2
0.1
0.1
0.2
0.2
0.2
0.6
0.2
1.8
1.1
0.2
0.2
0.2
0.4
0.5
1.8
0.1
0.2
0.5
3.8
0.7
0.6
1.2
0.7
0.8
0.8
0.4
0.2
0.2
0.8
0.9
3.8
0.2
0.7
0.8
0.9
0.7
1.2
0.8
1.7
1.6
2.5
0.9
0.3
0.4
1.0
0.6
2.5
0.3
JAN
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
mean
std dev
max
min
0.3
0.6
0.5
0.3
0.4
1.3
0.5
0.8
0.7
0.3
0.2
0.4
0.5
0.3
1.3
0.2
40
Table 2.26 Biochemical Oxygen Demand (mg/L) at the LCFRP stations for 2005.
5-Day Biochemical Oxygen Demand
month
JAN
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
median
mean
max
min
stdev
NC11
0.7
1.1
1.3
1.6
1.5
1.3
1.3
1.0
1.7
1.2
1.1
1.4
1.3
1.3
1.7
0.7
0.3
AC
0.9
1.3
1.5
1.5
2.6
1.7
1.3
1.3
1.8
2.2
0.9
1.8
1.5
1.6
2.6
0.9
0.5
ANC
1.2
1.5
1.4
1.8
1.5
2.0
2.3
2.2
2.8
1.6
1.5
1.6
1.6
1.8
2.8
1.2
0.5
SAR
1.0
0.8
1.0
3.2
2.0
1.9
1.0
1.5
4.2
1.1
1.4
0.8
1.3
1.7
4.2
0.8
1.1
GS
0.6
0.9
1.0
1.1
1.5
3.6
3.3
1.9
8.8
1.2
2.0
1.0
1.4
2.2
8.8
0.6
2.3
N403
1.1
1.5
1.1
1.3
1.4
SAR
2.9
2.8
3.0
7.1
5.2
4.3
5.0
4.6
9.0
3.9
3.7
2.1
4.1
4.5
9.0
2.1
2.0
GS
2.1
2.8
2.6
3.2
4.3
8.8
9.0
4.3
9.1
4.1
5.1
2.3
4.2
4.8
9.1
2.1
2.7
N403
3.0
4.4
3.0
3.6
3.8
3.2
1.4
1.3
1.3
1.3
1.5
3.2
1.1
0.6
ROC
0.6
1.2
1.4
1.8
1.2
1.6
1.2
1.6
1.9
2.4
1.0
1.5
1.5
1.5
2.4
0.6
0.5
BC117 NCF117
1.4
0.8
1.5
0.9
1.4
0.9
1.2
1.3
2.0
1.2
1.0
1.0
1.6
0.6
1.2
0.9
2.2
1.0
1.3
1.4
1.2
2.1
2.0
1.2
1.4
1.0
1.5
1.1
2.2
2.1
1.0
0.6
0.4
0.4
B210
0.9
0.8
0.9
1.0
1.2
0.9
0.5
1.1
0.9
0.8
1.1
1.3
0.9
1.0
1.3
0.5
0.2
LVC2
1.3
1.0
1.4
1.3
1.8
0.9
1.2
1.2
1.4
1.7
1.1
0.9
1.3
1.3
1.8
0.9
0.3
BBT
0.9
1.6
1.3
1.8
ROC
2.9
3.1
3.5
4.6
3.2
3.6
4.7
4.5
5.3
6.9
2.6
3.4
3.6
4.0
6.9
2.6
1.2
BC117 NCF117
3.2
2.6
4.0
2.8
4.4
2.8
3.3
3.6
5.0
3.5
2.6
3.2
6.3
2.9
3.8
2.9
5.3
3.0
4.1
4.4
3.5
5.3
4.1
2.9
4.1
3.0
4.1
3.3
6.3
5.3
2.6
2.6
1.0
0.8
B210
2.2
2.0
2.1
2.4
3.1
2.7
2.6
3.2
2.6
2.5
2.9
2.7
2.6
2.6
3.2
2.0
0.4
LVC2
3.8
2.3
3.7
2.9
4.3
2.9
4.5
3.8
4.7
4.8
3.7
2.6
3.8
3.7
4.8
2.3
0.8
BBT
2.8
3.2
3.5
4.1
1.3
0.8
1.1
1.2
1.0
1.2
1.2
1.2
1.8
0.8
0.3
20-Day Biochemical Oxygen Demand
month
JAN
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
median
mean
max
min
stdev
NC11
2.2
2.9
3.4
3.7
3.3
3.2
4.5
3.2
4.2
2.9
2.6
3.9
3.3
3.3
4.5
2.2
0.7
AC
2.4
3.4
4.0
3.8
6.2
3.9
5.0
3.9
5.5
6.1
2.3
4.9
4.0
4.3
6.2
2.3
1.3
ANC
3.6
4.1
3.5
4.5
4.4
5.1
8.9
6.4
7.6
5.0
3.9
3.5
4.5
5.0
8.9
3.5
1.7
8.7
5.3
3.6
2.8
3.6
4.2
8.7
2.8
1.8
2.9
3.5
3.2
3.5
2.7
3.4
3.3
3.3
4.1
2.7
0.4
41
Table 2.27 Fecal Coliform Bacteria concentrations (CFU/100 mL) at the LCFRP stations for 2005. The NC State standard for
human contact is 200 CFU/100 mL.
month
NAV
HB
BRR
M61
M54
M42
M35
M23
M18
SPD
month
NC11
AC
DP
IC
NCF6
JAN
94
15
16
47
68
36
11
82
27
91
9
41
45
30
94
9
34
52
13
17
44
60
45
48
64
27
36
73
41
43
17
73
13
39
49
19
20
49
40
41
11
164
5
55
18
45
43
40
164
5
30
29
6
21
43
26
35
4
27
5
8
18
27
21
12
43
4
16
25
4
24
44
23
24
7
64
5
5
27
9
22
17
64
4
15
6
2
7
34
23
8
1
55
5
5
18
14
15
15
55
1
9
3
1
1
13
4
3
1
9
5
5
5
9
5
4
13
1
4
2
1
1
11
5
2
1
18
5
5
5
9
5
5
18
1
4
11
1
2
14
6
21
2
9
5
5
45
9
11
12
45
1
7
JAN
Geomean
100
13
23
50
57
34
54
18
5
182
27
45
51
46
182
5
35
Geomean
17
41
44
42
8
10
40
82
36
9
5
120
38
33
120
5
25
12
46
41
41
3
280
117
18
5
27
18
64
56
74
280
3
28
47
31
39
43
15
16
34
55
9
18
18
55
32
16
55
9
27
47
23
42
70
11
20
46
46
45
9
5
36
33
19
70
5
26
66
27
19
45
53
48
29
36
27
36
55
41
40
13
66
19
38
month
ANC
SAR
GS
NC403
PB
LRC
ROC
BC117
BCRR
month
6RC
LCO
GCO
SR
BRN
HAM
JAN
57
44
27
41
40
45
520
320
300
27
9
36
122
157
520
9
60
280
54
52
44
31
40
30
1,000
270
109
36
73
168
265
1000
30
83
28
23
22
18
78
222
680
470
1,100
36
200
9
241
329
1100
9
83
44
41
12
15
99
70
66
49
104
300
275
6,000
500
1,300
350
3,700
115
1069
1785
6000
49
319
92
59
68
42
117
172
27
182
109
82
109
500
130
120
500
27
98
180
86
34
49
57
56
30
146
73
91
182
55
87
51
182
30
73
109
99
66
143
53
49
440
240
200
64
700
270
203
186
700
49
142
54
62
74
62
7
265
6,000
1,400
230
45
1,200
91
791
1634
6000
7
159
JAN
41
50
43
99
12
58
88
700
36
100
91
59
115
178
700
12
66
59
28
27
47
9
26
58
145
100
59
27
100
57
38
145
9
45
26
23
25
43
16
23
64
210
200
32
27
45
61
66
210
16
41
22
21
94
14
12
93
800
320
3,900
190
36
14
460
1060
3900
12
80
60
44
44
59
47
134
67
220
182
27
45
175
92
64
220
27
73
76
88
400
90
44
62
74
164
200
9
145
32
115
101
400
9
80
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
mean
std dev
max
min
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
mean
std dev
max
min
Geomean
1,100
118
73
41
171
330
1100
12
61
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
mean
std dev
max
min
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
mean
std dev
max
min
Geomean
month NCF117
JAN
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
mean
std dev
max
min
Geomean
37
16
37
23
22
43
82
9
55
3
18
36
32
21
82
3
24
B210
COL
LVC2
SC-CH
91
25
45
89
38
48
60
82
55
36
9
95
56
27
95
9
48
27
20
40
21
30
27
84
55
73
27
5
14
35
23
84
5
28
45
25
23
30
28
49
58
91
64
33
64
45
46
19
91
23
42
100
35
64
70
18
73
95
173
55
82
73
41
73
38
173
18
64
42
Figure 2.1 Mean salinity at the LCFRP mainstem estuary stations.
30
25
Saliinity (psu)
20
15
10
5
0
NAV
HB
BRR
M61
M54
July 1996-December 2004
M42
M35
M23
January -December 2005
M18
SPD
NCF6
43
Figure 2.2 Mean Dissolved Oxygen concentrations at the LCFRP mainstem stations.
10
9
7
6
NC State
Standard
5
4
3
2
1
July 1996-December 2004
January -December 2005
BBT
B210
NCF6
NCF117
M18
M23
M35
M42
M54
M61
BRR
HB
NAV
IC
DP
AC
0
NC11
Dissolved Oxygen (mg/L)
8
44
Figure 2.3 Mean Field Turbidity levels at the LCFRP mainstem stations.
50
NC State freshwater
standard
45
40
30
NC State saltwater
standard
25
20
15
10
5
July 1996-December 2004
January -December 2005
BBT
B210
NCF6
NCF117
M18
M23
M35
M42
M54
M61
BRR
HB
NAV
IC
DP
AC
0
NC11
Field Turbidity (NTU)
35
45
Figure 2.4 Mean Light Attenuation at the LCFRP mainstem stations.
5
Light Attenuation (k)
4
3
2
1
0
NC11
AC
DP
IC
NAV
HB
BRR
M61
July 1996-December 2004
M54
M42
M35
M23
January -December 2005
M18
NCF6
BBT
46
Figure 2.5 Mean Total Nitrogen concentrations at the LCFRP mainstem stations.
1,800
1,600
1,200
1,000
800
600
400
200
July 1996-December 2004
January -December 2005
B210
NCF6
NCF117
M18
M23
M35
M42
M54
M61
BRR
HB
NAV
IC
DP
AC
0
NC11
Total Nitrogen (mg/L)
1,400
47
Figure 2.6 Mean Nitrate-Nitrite concentrations at the LCFRP mainstem stations.
700
600
400
300
200
100
July 1996-December 2004
January -December 2005
BBT
B210
NCF6
NCF117
M18
M23
M35
M42
M54
M61
BRR
HB
NAV
IC
DP
AC
0
NC11
Nitrate-Nitrite (mg/L)
500
48
Figure 2.7 Mean Ammonium concentrations at the LCFRP mainstem stations.
140
120
80
60
40
20
July 1996-December 2004
January -December 2005
BBT
B210
NCF6
NCF117
M18
M23
M35
M42
M54
M61
BRR
HB
NAV
IC
DP
AC
0
NC11
Ammonium (mg/L)
g/L)
100
49
Figure 2.8 Mean Total Kjeldahl Nitrogen concentrations at the LCFRP mainstem
stations.
1200
800
600
400
200
July 1996-December 2004
January -December 2005
B210
NCF6
NCF117
M18
M23
M35
M42
M54
M61
BRR
HB
NAV
IC
DP
AC
0
NC11
Total Kjeldahl Nitrogen ((mg/L)
1000
50
Figure 2.9 Mean Total Phosphorus concentrations at the LCFRP mainstem stations.
200
180
140
120
100
80
60
40
20
July 1996-December 2004
January -December 2005
B210
NCF6
NCF117
M18
M23
M35
M42
M54
M61
BRR
HB
NAV
IC
DP
AC
0
NC11
Total Phosphorus (m
mg/L)
160
51
Figure 2.10 Mean Orthophosphate concentrations at the LCFRP mainstem stations.
100
90
70
60
50
40
30
20
10
July 1996-December 2004
January -December 2005
BBT
B210
NCF6
NCF117
M18
M23
M35
M42
M54
M61
BRR
HB
NAV
IC
DP
AC
0
NC11
Orthophosphate (mg/L)
g/L)
80
52
Figure 2.11 Mean Chlorophyll a concentrations at the LCFRP mainstem stations.
8
7
Chlorophyll a (mg/L)
g/L)
6
5
4
3
2
1
0
July 1996-December 2004
January -December 2005
53
Figure 2.12 Mean Fecal Coliform Bacteria concentrations at the LCFRP mainstem
stations.
140
100
80
60
40
20
July 1996-December 2004
January -December 2005
B210
NCF6
NCF117
M18
M23
M35
M42
M54
M61
BRR
HB
NAV
IC
DP
AC
0
NC11
Fecal Coliform Bacteria (cfu/100mL)
120
54
3.0 Water Quality Evaluation by Subbasin in the
Lower Cape Fear River System
Matthew R. McIver, Michael A. Mallin, and James F. Merritt
Aquatic Ecology Laboratory
Center for Marine Science
University of North Carolina Wilmington
3.0 Water Quality Evaluation by Subbasin
This section details an evaluation of water quality within each subbasin for dissolved
oxygen, turbidity, chlorophyll a, fecal coliform bacteria and some nutrient species at the
LCFRP sampling sites. Monthly data from January to December 2005 are used in the
comparisons.
3.1 Introduction
The NC Division of Water Quality prepares a basinwide water quality plan for each of
the seventeen major river basins in the state every five years (NCDENR, DWQ Cape
Fear River Basinwide Water Quality Plan, October 2005). The basinwide approach is a
nonregulatory watershed-based approach to restoring and protecting the quality of
North Carolina’s surface waters. The first basinwide plan for the Cape Fear River was
completed in 1996 and five-year interval updates have been completed in 2000 and
2005.
The goals of the basinwide program are to:
- Identify water quality problems and restore full use to Impaired waters.
- Identify and protect high value resource waters.
- Protect unimpaired waters while allowing for reasonable economic growth.
DWQ accomplishes these goals through the following objectives:
- Collaborate with other agencies to develop appropriate management strategies.
- Assure equitable distribution of waste assimilative capacity.
- Better evaluate cumulative effects of pollution.
- Improve public awareness and involvement.
The US Geological Survey (USGS) identifies 6 major hydrological areas in the Cape
Fear River Basin. Each of these hydrologic areas is further divided into subbasins by
DWQ. There are 24 subbasins within the Cape Fear River basin, each denoted by 6digit numbers, 03-06-01 to 03-06-24 (NCDENR-DWQ, October 2005).
All surface waters in the state are assigned a primary classification that is appropriate to
the best uses of that water. North Carolina’s Water Quality Standards Program adopted
classifications and water quality standards for all the state’s river basins by 1963. The
program remains consistent with the Federal Clean Water Act and its amendments.
55
DWQ assesses ecosystem health and human health risk through the use of five use
support categories: aquatic life, recreation, fish consumption, water supply and shellfish
harvesting. [Note: All waters east of Interstate 95 are considered impaired for fish
consumption due to mercury levels in fish tissue.] These categories are tied to the uses
associated with the primary classifications applied to NC rivers and streams. Waters
are supporting if data and information used to assign a use support rating meet the
criteria for that use category. If these criteria are not met then the waters are Impaired.
Waters with inconclusive data and information are Not Rated. Waters where no data or
information is available to make an assessment are rated No Data.
For ambient water quality monitoring criteria, DWQ uses water quality data collected by
both their own monitoring system as well as several NPDES discharger coalitions
including the Lower Cape Fear River Program. The parameters used to assess water
quality in the aquatic life category include dissolved oxygen, pH, chlorophyll a and
turbidity. DWQ rates use support based on whether the NC State Water Quality
Standard is exceeded as listed below:
Standard exceeded in < 10% of samples
Standard exceeded in > 10% of samples
Less than 10 samples collected
DO and pH standard exceeded in swamps
=
=
=
=
Supporting
Impaired
Not Rated
Not Rated
*Some standards are written with more specific criteria and the reader should refer to
the Basinwide Water Quality plan for complete details about the DWQ rating system
(refer).
3.2 UNCW Aquatic Ecology Laboratory Evaluation
The UNCW Aquatic Ecology Laboratory (AEL) has developed an evaluation system that
incorporates some of the guidelines used by DWQ and utilizes data collected by the
Lower Cape Fear River Program. This approach determines a water quality “status” for
the parameters dissolved oxygen, chlorophyll a, fecal coliform bacteria, and turbidity
and the nutrient species nitrate and total phosphorus. For dissolved oxygen, chlorophyll
a, and fecal coliform bacteria we compare LCFRP data to the N.C. Water Quality
Standards (http://h2o.enr.state.nc.us/csu/index.htm).
For Total Phosphorus and Nitrate/Nitrite the water quality status is based on levels
noted to be problematic in the scientific literature and our own published research.
Based on data from four years of nutrient addition bioassay experiments using water
from the Black and Northeast Cape Fear Rivers, Colly Creek and Great Coharie Creek,
the UNCW-AEL considers nitrate levels of 200 g/L and total phophorus levels of 500
g/L harmful to water quality. These nutrient levels may lead to algal blooms, high
bacteria levels and high Biochemical Oxygen Demand (BOD) in blackwater streams
(Mallin et al., 2001; 2002; 2004). Water quality status for nutrient species was not
evaluated at the mainstem stations on the Cape Fear River because its waters are quite
different than the blackwater areas.
Our system lists a sampling location as having good quality (G) if standard is exceeded
in none or 1 sample out of 12 measurements, fair quality (F) if standard is exceeded in 2
56
or 3 or 12 of measurements, or poor quality (P) if standard is exceeded in 4-12 out of 12
measurements.
The 36 stations monitored by the LCFRP by subbasin:
Subbasin #
03-06-16
LCFRP Stations
BRN, HAM, NC11
03-06-17
LVC2, AC, DP, IC, NAV, HB, BRR,
M61, M54, M42, M35, M23, M18, SPD
03-06-18
SR
03-06-19
6RC, LCO, GCO
03-06-20
COL, B210, BBT
03-06-21
N403
03-06-22
SAR, GS, PB, LRC, ROC
03-06-23
ANC, BC117, BCRR, NCF6, NCF117,
SC-CH
3.2 Methods
Each subbasin is addressed separately with a description and map showing the LCFRP
stations. This will be followed by a summary of the information published in the Cape
Fear River Basinwide Water Quality Plan, October 2005 and water quality status
discussion using the UNCW-AEL approach for the 2005 data.
57
3.3 Cape Fear River Subbasin 03-06-16
Location:
Cape Fear River upstream and downstream of Elizabethtown
Counties:
Bladen, Columbus, Cumberland, Pender
Water bodies:
Cape Fear River
Municipalities:
Elizabethtown, Dublin, White Lake, East Arcadia, Tar Heel
NPDES Dischargers: 7 @ 13.7 million gallons per day
Concentrated Swine Operations: 50
LCFRP monitoring stations (DWQ #):
BRN (B8340050), HAM (B8340200), NC11 (B8360000)
NC DWQ monitoring stations (DWQ #):
Six ambient monitoring stations
BRN
HAM
NC11
58
Subbasin 03-06-16 includes the Cape Fear River and many streams that drain coastal plain
wetlands and bay lakes. Most of the watershed is forested with some agriculture present.
The CFR Basinwide Water Quality Plan lists the following ratings for this subbasin:
Aquatic Life
Supporting
Not Rated
Not Rated
No Data
No Data
101.5 freshwater miles
40.1 freshwater miles
1,593.2 freshwater acres
131.4 freshwater miles
917.6 freshwater acres
Recreation
Supporting
Not Rated
No Data
No Data
115.1 freshwater miles
4.8 freshwater miles
153.1 freshwater miles
2,510.8 freshwater acres
*Brown’s Creek, rated as impaired in the 2000 CFRBWQP, was upgraded in the 2005 plan
(NCDENR DWQ CFRWQBP, July 2000 and NCDENR DWQ CFRWQBP, October 2005).
Lower Cape Fear River Program Evaluation
Data collection: NC11 since June 1995, BRN & HAM since February 1996
Sampling relevance: Represents water entering the Lower Cape Fear River watershed from
the middle basin (NC11). There are also several concentrated animal operations within the
area (BRN and HAM).
BRN - representative of small tributaries
of the Cape Fear River
NC11 - main stem of Cape Fear River,
deep channel, freshwater
with slight tidal influence
59
The sites BRN and NC11 were found to have a good quality status for dissolved oxygen,
meeting the North Carolina State Standard of 5.0 mg/L in all sampled months (Table 3.3.1).
HAM, a small channeled tributary, had a fair status with dissolved oxygen levels falling below
5.0 mg/L in three of the twelve sampled months (25% of the time). The lowest concentrations
of dissolved oxygen at HAM were 3.4 mg/L, found in September 2005. The dissolved oxygen
concentrations for Hammonds Creek are represented graphically in Figure 3.3.1.
All sites within this subbasin were found to have a good quality status for chlorophyll a
concentrations (Table 3.3.1). The North Carolina State Standard for chlorophyll a of 40 g/L
was not exceeded at any station during 2005.
Fecal coliform bacteria concentrations were low at NC11, which had a good quality status with
no sample over the NC State Standard for human contact waters of 200 CFU/100mL in 2005
(Table 3.3.1). BRN received a good quality status for fecal coliform bacteria concentrations,
exceeding the standard 8% of the time. HAM had a good quality status for fecal coliform
bacteria concentrations, exceeding the NC State Standard in 8% of samples (Figure 3.3.2).
All sites within this subbasin were found to have a good quality status for turbidity
concentrations (Table 3.3.1). The North Carolina State Standard for turbidity in freshwater of
50 NTU was not exceeded at any station during 2005.
For nutrients, BRN and HAM (NC11 is a mainstem station) were found to have a good quality
status for Total Phosphorus (Table 3.3.1). For Nitrate both BRN and HAM had a fair quality
status with exceedances of 25% and 17%, respectively.
Table 3.3.1 UNCW AEL evaluation for subbasin 03-06-16
Station
Dissolved Oxygen
Field Turbidity
Chlorophyll a
Fecal Coliform
Nitrate
Total
Phosphorus
BRN
G/G
G
G
G
F
G
HAM
F/F
G
G
G
F
G
NC11
G
G
G
G
na
na
60
Figure 3.3.1 Dissolved Oxygen concentrations (mg/L) at HAM during 2005. The dashed line
is the NC State Standard of 5.0 mg/L.
14
Dissloved Oxygen (mg/L)
12
10
8
6
4
2
0
JAN
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
Figure 3.3.2. Fecal Coliform Bacteria concentrations (CFU/100mL) at HAM during 2005.
The dashed line is the NC State Standard for human contact of 200 CFU/100mL.
450
Fecal Coliform Bacteria (cfu)
400
350
300
250
200
150
100
50
0
JAN
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
61
3.4 Cape Fear River Subbasin 03-06-17
Location:
Cape Fear River near Riegelwood, downstream to estuarine area
near Southport
Counties:
Columbus, Pender, Brunswick, New Hanover
Waterbodies:
Cape Fear River and Estuary
Municipalities:
Wilmington, Southport
NPDES Dischargers: 41 @ 99.9 million gallons per day
Concentrated Swine Operations: 7
LCFRP monitoring stations (DWQ #):
LVC (B8445000), AC (B8450000), DP (B8460000), IC (B9030000),
NAV (B9050000), HB (B9050100), BRR (B9790000), M61 (B9750000),
M54 (B9795000), M42 (B9845100), M35 (B9850100), M23 (B9910000),
M18 (B9921000), SPD (B9980000)
DWQ monitoring stations:
NAV (B9050000), M61 (B9750000), M54(B9795000)
LVC2
AC
DP
IC
NAV
HB
BRR
M61
M54
M42
M35
M23
M18
SPD
62
Subbason 03-06-17 includes the mainstem of the Cape Fear River, the Cape Fear River
Estuary and many streams that drain the areas west of the River. Most of the watershed is
forested with some urban areas including Wilmington and Southport.
CFR Basinwide Water Quality Plan lists the following ratings for this subbasin:
Aquatic Life
Supporting
Not Rated
Impaired
Supporting
Not Rated
Not Rated
No Data
No Data
No Data
No Data
14,125.4 saltwater acres
2.0 saltwater acres
6,457.0 saltwater acres
75.4 freshwater miles
22.3 freshwater miles
406.9 freshwater acres
2,859.2 saltwater acres
215.4 freshwater miles
844.5 freshwater acres
22.8 coast miles
Recreation
Supporting
Impaired
Supporting
Not Rated
Impaired
No Data
No Data
No Data
No Data
21,092.3 saltwater acres
96.6 saltwater acres
44.1 freshwater miles
5.6 coast miles
4.7 coast miles
2,254.6 saltwater acres
269.1 freshwater miles
1,251.5 freshwater acres
12.5 coast miles
Lower Cape Fear River Program Assessment
Data collection: Most stations since 1995, all sampled since 1998
Sampling relevance: Highly important estuary for fisheries productivity. Also receives point
source discharge and non-point source pollution.
AC - representative of riverine system
channel
HB - riverine station, upstream of
HB – upper estuary, upstream of
Wilmington
63
M35 – represents wide estuary
Sites given a good quality status for dissolved oxygen include: AC, BRR, M54, M42, M35,
M23, and M18 (Table 3.4.1). Sites having a fair quality status for dissolved oxygen, with the
percentage of samples not meeting the standard of 5.0 mg/L shown in parentheses: DP
(25%), IC (25%), NAV (17%), HB (25%), M61 (17%). LVC2 had a poor water quality status
with 42% of samples falling below the standard.
All sites within this subbasin were found to be good quality in terms of chlorophyll a
concentrations (Table 3.4.1). None of the sampled locations exceeded the 40 g/L North
Carolina State Standard on any sample occasion.
All sites within this subbassin were rated as good quality for fecal coliform bacteria
concentrations (Table 3.4.1). No site exceeded the 200 CFU/100mL NC State Standard for
human contact waters. Areas in the middle estuary at M35 down to mouth of the river can
have harvestable populations of shellfish including oysters (Crassotrea virginica) and clams
(Mercenaria mercenaria). The NC State fecal coliform bacteria standard for shellfishing states
that the geometric mean cannot exceed 14 CFU/100mL and no more than 10% of samples
may exceed 43 CFU/100mL. All of the LCFRP stations in shellfishing areas met the NC State
standard.
All the LCFRP sites in this subbasin had a good quality status for turbidity (Table 3.4.1). The
station NAV and those upstream were evaluated using the NC State Standard for freshwater of
50 NTU while all stations downstream of NAV were evaluated with the NC State Standard for
brackish waters of 25 NTU.
64
Table 3.4.1 UNCW AEL evaluation for subbasin 03-06-17
Station
Dissolved Oxygen
Field Turbidity
Chlorophyll a
Fecal Coliform
Nitrate
Total
Phosphorus
LVC2
P
G
G
G
na
na
AC
G
G
G
G
na
na
DP
F
G
G
G
na
na
IC
F
G
G
G
na
na
NAV
F
G
G
G
na
na
HB
F
G
G
G
na
na
BRR
G
G
G
G
na
na
M61
F
G
G
G
na
na
M54
G
G
G
G
na
na
M42
G
G
G
G
na
na
M35
G
G
G
G
na
na
M23
G
G
G
G
na
na
M18
G
G
G
G
na
na
SPD
G
G
G
G
na
na
65
Figure 3.4.1 Dissolved Oxygen concentrations (mg/L) at NAV, HB and M61 for 2005. The
dashed line shows the NC State Standard of 5.0 mg/L.
12
Dissolved Oxygen (mg/L)
10
8
6
4
NAV
HB
2
M61
0
JAN
FEB MAR APR MAY JUN
JUL
AUG SEP OCT NOV DEC
66
3.5 Cape Fear River Subbasin 03-06-18
Location:
South River headwaters above Dunn down to Black River
Counties:
Bladen, Cumberland, Harnett, Johnston, Sampson
Waterbodies:
South River, Mingo Swamp
Municipalities:
Dunn, Roseboro
NPDES Dischargers: 2 @ 0.08 million gallons per day
Concentrated Swine Operations: 105
LCFRP monitoring stations (DWQ #): SR (B8470000)
DWQ monitoring stations:
none
SR
67
This subbasin is located on the inner coastal plain and includes the South River which
converges with the Great Coharie Creek to form the Black River, a major tributary of the Cape
Fear River. Land use is primarily agriculture including row crops and concentrated animal
operations.
CFR Basinwide Water Quality Plan lists the following ratings for this subbasin:
Aquatic Life
Not Rated 52.1 freshwater miles
Not Rated 1,454.2 freshwater acres
No Data
242.5 freshwater miles
Recreation
Supporting
No Data
No Data
52.1 freshwater miles
242.5 freshwater miles
1,454.2 freshwater acres
Lower Cape Fear River Program Assessment
Data collection: Since February 1996
Sampling relevance: Below City of Dunn, hog operations in watershed
SR – a slow black water tributary
SR was found to have a poor water quality status for dissolved oxygen concentrations (Table
3.5.1). The North Carolina State Standard of 5.0 mg/L was not met 58% of the time and the
swampwater standard of 4.0 mg/L was not 58% of the time. The lowest levels were found in
late summer and early fall (Figure 3.5.1).
This site was found to be good quality for chlorophyll a, with no samples exceeding the 40 g/L
North Carolina State Standard (Table 3.5.1).
SR had a fair water quality status for fecal coliform bacteria concentrations, exceeding the NC
State Standard of 200 CFU/100mL in 27% of samples (Table 3.5.1). The highest
concentrations were in September (3,900 CFU/100mL) and July (800 CFU/100mL).
SR had a good water quality status for turbidity, nitrate and phosphorus (Table 3.5.1).
68
Table 3.5.1 UNCW AEL evaluation for subbasin 03-06-18
Station
Dissolved Oxygen
Field Turbidity
Chlorophyll a
Fecal Coliform
Nitrate
Total
Phosphorus
SR
P
G
G
F
G
G
Figure 3.5.1 Dissolved Oxygen concentrations (mg/L) at SR during 2005. The dashed line
shows the NC State Standard for swampwater of 4.0 mg/L.
12
Dissolved Oxygen (mg/L)
10
8
6
4
2
0
JAN
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
69
3.6 Cape Fear River Subbasin 03-06-19
Location:
Three main tributaries of Black River near Clinton
Counties:
Sampson
Waterbodies:
Black River, Six Runs Ck., Great Coharie Ck., Little Coharie Ck.
Municipalities:
Clinton, Newton Grove, Warsaw
NPDES Dischargers: 8 @ 6.8 million gallons per day
Concentrated Swine Operations: 374
LCFRP monitoring stations (DWQ #):
LCO (B8610001), GCO (B8604000), 6RC (B8740000)
DWQ monitoring stations: none
GCO
LCO
6 RC
70
This subbasin is located in the coastal plain within Sampson County. Land adjacent to
the Black River is primarily undisturbed forest. There is are numerous concentrated
swine operations within this subbasin.
CFR Basinwide Water Quality Plan lists the following ratings for this subbasin:
Aquatic Life
Supporting 71.3 freshwater miles
Not Rated 99.7 freshwater miles
No Data
338.4 freshwater miles
Recreation
Supporting
Not Rated
No Data
153.0 freshwater miles
8.8 freshwater miles
347.6 freshwater miles
Lower Cape Fear River Program Assessment
Data collection: February 1996 to present
Sampling relevance: Many concentrated animal operations (CAOs) within the
watershed, reference areas for point and nonpoint source pollution
GCO - blackwater stream, drains
riparian wetlands
LCO and 6RC had a good water quality status for dissolved oxygen concentrations,
with no measurements below the NC State Standard of 5.0 mg/L or 4.0 mg/L for
swampwater (Table 3.6.1). GCO had a fair water quality status for dissolved oxygen
concentrations, not meeting the standard of 5.0 mg/L in 17% of the samples. When
evaluated using the swampwater standard of 4.0 mg/L, GCO had a good quality
status, with 8% of samples below the 4.0 mg/L swamp water standard.
All sites within this subbasin had a good water quality status for chlorophyll a and
turbidity concentrations (Table 3.6.1).
GCO had a fair water quality status for fecal coliform bacteria with 17% of sampes
exceeding the NC State human contact standard of 200 CFU/100mL (Table 3.6.1).
Both LCO and 6RC had good water quality status for fecal coliform bacteria.
Nitrate levels were high in Six Runs Creek (6RC), exceeding 200 g/L for 67% of the
samples, therefore 6RC was given a poor water quality status (Table 3.6.1, Figure
3.6.1). Both LCO and GCO had a fair water quality status for nitrate, having nitrate
levels above 200 g/L in 25% of the samples.
71
Table 3.6.1 UNCW AEL evaluation for subbasin 03-06-19
Station
Dissolved Oxygen
Field Turbidity
Chlorophyll a
Fecal Coliform
Nitrate
Total
Phosphorus
6RC
G
G
G
G
P
G
LCO
G
G
G
G
F
G
GCO
F
G
G
F
F
G
Figure 3.6.1 Nitrate concentrations (g/L) at 6RC, LCO, and GCO during 2005. The
dashed line shows level considered problematic in black water streams.
1,200
1,000
Nitrate ( g/L)
6RC
LCO
800
GCO
600
400
200
0
JAN
FEB
MAR APR MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
72
3.7 Cape Fear River Subbasin 03-06-20
Location:
Lower reach of Black River
Counties:
Pender
Waterbodies:
Black River, Colly Creek, Moores Creek
Municipalities:
Town of White Lake, Currie, Atkinson
NPDES Dischargers: 2 at 0.82 million gallons per day
Concentrated Swine Operations: 18
LCFRP monitoring stations (DWQ #):
COL (B8981000), B210 (B9000000), BBT (none)
DWQ monitoring stations: none
B210
COL
BBT
73
This subbasin is located on the coastal plain in Pender County and the land is mostly
forested with some agriculture. The streams in this watershed typically have acidic
black waters. The Black River in this area has been classified as Outstanding
Resource Waters (ORW) (NCDENR DWQ Cape Fear River Basinwide Water Quality
Plan, October 2005).
The CFR Basinwide Water Quality Plan lists the following ratings for this subbasin:
Aquatic Life
Supporting
Not Rated
Not Rated
No Data
13.0 freshwater miles
77.9 freshwater miles
576.0 freshwater acres
143.8 freshwater acres
Recreation
Supporting
No Data
No Data
34.9 freshwater miles
199.8 freshwater miles
576.0 freshwater miles
Lower Cape Fear River Program Assessment
Data collection: February 1996 to present
Sampling relevance: Colly Creek is a pristine swamp reference site, B210 and
BBT are middle and lower Black River sites
large
COL – blackwater stream, drains
swamp area, very low pH
B210 - Black River at Hwy 210 bridge
74
All three sites had a good water quality status for dissolved oxygen when using the NC
State swampwater standard of 4.0 mg/L (Table 3.7.1). When using the 5.0 mg/L
standard, COL and B210 had a fair water quality status with levels below the standard
17% and 25% of the samples, respectively. BBT had a poor water quality status with
levels below 5.0 mg/L 33% of the time.
Chlorophyll a, Field Turbidity, and Nutrient concentrations were low for each site within
this subbasin and all sites had a good water quality status for these parameters (Table
3.7.1).
Fecal coliform bacteria concentrations were generally low, and COL and B210 had a
good water quality status (Table 3.7.1). No single sample was above the NC State
standard for human contact (200 cfu/100 mL). BBT samples were not analyzed for
fecal coliform bacteria.
Table 3.7.1 UNCW AEL evaluation for subbasin 03-06-20
Station
Dissolved Oxygen
Field Turbidity
Chlorophyll a
Fecal Coliform
Nitrate
Total
Phosphorus
B210
F/G
G
G
G
G
G
COL
F/G
G
G
G
G
G
BBT
P/G
G
G
G
G
G
75
3.8 Cape Fear River Subbasin 03-06-21
Location:
Headwaters of NE Cape Fear River below Mount Olive
Counties:
Duplin, Wayne
Waterbodies:
Northeast Cape Fear River
Municipalities:
Mount Olive
NPDES Dischargers: 6 @ 1.4 million gallons per day
Concentrated Swine Operations: 75
LCFRP monitoring stations (DWQ#):
DWQ monitoring stations:
NC403 (B9090000)
NC403
NC403
This subbasin includes the headwaters of the Northeast Cape Fear River and small
tributaries. This section of the NE Cape Fear River is very slow moving and somewhat
congested with macrophytic growth. Most of the watershed is forested and there is
significant agriculture in the basin.
The CFR Basinwide Water Quality Plan lists the following ratings for this subbasin:
Aquatic Life
Supporting 21.7 freshwater miles
Not Rated 38.9 freshwater miles
No Data
84.7 freshwater miles
Recreation
Supporting
No Data
57.3 freshwater miles
88.1 freshwater miles
76
Lower Cape Fear River Program Assessment
Data collection: June 1997 – present
Sampling relevance: Below Mount Olive Pickle Plant
NC403 - slow moving headwaters of
NE Cape Fear River
*NC403 had a reduced number of sampling occasions due to bridge construction and
limited access. Samples were not obtained during June, July and August 2005
The NC403 site had a poor water quality status for dissolved oxygen concentrations, not
meeting the NC State Standard of 5.0 mg/L in 66% of all samples (Table 3.8.1). When
using the NC swamp water standard of 4.0 mg/L, NC403 also had a poor water quality
status, not meeting the standard 33% of the time. Because of the missing data during
the time of year likely to have the lowest dissolved oxygen levels, we must assume that
these exceedance percentages would be much higher with twelve months of data.
NC403 had a good water quality status in terms of chlorophyll a, yet there is very high
aquatic macrophyte biomass present, often times completely covering and blocking the
waterway (Table 3.8.1). As we have noticed at several of our stations over the years,
Chlorophyll a, a measurement of phytoplankton biomass, and often used as an indicator
of eutrophic conditions, is not always adequate to determine problematic conditions with
regard to aquatic flora.
Fecal Coliform Bacteria and Field Turbidity levels indicated a good water quality status
at NC 403 (Table 3.8.1). One fecal coliform bacteria sample exceeded the NC State
standard for human contact (200 CFU/100 mL), while no field turbidity levels exceeded
the NC State standard.
High nitrate levels at NC403 led to a poor water quality status (Table 3.8.1). Nitrate-N
concentrations >200 g/L occurred for 42% of the samples at NC403 during 2005.
UNCW AEL researchers are concerned about the elevated nitrate levels that are
periodically found at this site since these levels increase the likelihood of algal blooms
and excessive aquatic macrophyte growth. Total phosphorus concentrations exceeded
the UNCW AEL recommended harmful level on one occasion, giving this site a good
77
water quality status for TP. Nutrient concentrations are shown graphically for NC403 in
Figure 3.8.2.
Table 3.8.1 UNCW AEL evaluation for subbasin 03-06-21.
Station
Dissolved Oxygen
Field Turbidity
Chlorophyll a
Fecal Coliform
Nitrate
Total
Phosphorus
NC403
P/P
G
G
G
P
G
Figure 3.8.1 Dissolved Oxygen concentrations (mg/L) at NC403 during 2005. The
dashed line shows the NC State Standard of 4.0 mg/L for swampwater.
12
Dissolved Oxygen (mg/L)
10
8
6
4
2
0
JAN
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
78
Figure 3.8.2 Nitrate concentrations (g/L) at NC403 for 2005. The dashed line
represents levels at which excessive algal growth may occur (200 g/L).
1,200
Nitrate-N (mg/L)
1,000
800
600
400
200
0
JAN
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
79
3.9 Cape Fear River Subbasin 03-06-22
Location:
NE Cape Fear River and tributaries in the vicinity of Kenansville
Counties:
Duplin
Waterbodies:
Northeast Cape Fear River, Rockfish Creek
Municipalities:
Beulaville, Kenansville, Rose Hill and Wallace
NPDES Dischargers: 13 @ 9.9 million gallons per day
Concentrated Swine Operations: 449
LCFRP monitoring stations (DWQ #):
PB (B9130000), GS (B9191000), SAR (B9191500), LRC (9460000)
ROC (B9430000)
DWQ monitoring stations: none
PB
GS
SAR
LRC
ROC
80
Land coverage in this watershed is mostly forested with significant agriculture, including
row crops and a dense concentration of animal operations (poultry and swine).
The CFR Basinwide Water Quality Plans lists the following ratings for this subbasin:
Aquatic Life
Supporting
Not Rated
Impaired
No Data
51.1 freshwater miles
72.1 freshwater miles
50.1 freshwater miles
408.8 freshwater miles
Recreation
Supporting
Not Rated
No Data
73.2 freshwater miles
3.0 freshwater miles
505.9 freshwater miles
Lower Cape Fear River Program Assessment
Data collection: February 1996 to present
Sampling relevance: Below point and non-point source discharges
PB – slow moving swamp-like
stream
ROC - Rockfish Creek below
Wallace
81
For the Dissolved Oxygen standard of 5.0 mg/L, LRC and ROC had a good water
quality status and PB had a fair water quality status (Table 3.9.1). GS and SAR both
had a poor water quality status with levels below the standard 67% and 33% of the time,
respectively. Using the swampwater standard of 4.0 mg/L, SAR, PB, LRC and ROC
had a good water quality status. GS had a poor water quality status with levels below
the standard 67% of the time. The Dissolved Oxygen concentrations for GS are shown
graphically in Figure 3.9.1.
For Chlorophyll a concentrations all sites except PB had a good water quality status
(Table 3.9.1). PB had a fair status with levels above the 40 mg/L standard 17% of the
time.
For Fecal Coliform Bacteria concentration, using the NC State standard of 200 CFU/100
mL for human contact, LRC and ROC had a good water quality status and SAR had a
fair status (Table 3.9.1). GS and PB had a poor water quality status with 42% and 58%
of samples above the standard, respectively. Fecal coliform bacteria concentrations for
GS and PB are shown graphically in Figure 3.9.2.
All sites had a good water quality status for Field Turbidity concentrations (Table 3.9.1).
Mean levels were less than 12 NTU for all sites within this subbasin for the 2005.
For Nitrate, GS had a good water quality status and PB was fair (Table 3.9.1). SAR,
LRC, and ROC all had a poor water quality status with levels exceeding the UNCW AEL
standard (200 g/L) 58%, 33%, and 50% of the time, respectively. Nitrate levels for
SAR, LRC and ROC are shown graphically in Figure 3.9.3.
For Total Phosphorus SAR, GS, LRC and ROC had a good water quality status (Table
3.9.1). PB had a fair status, exceeding the UNCW AEL standard in 17% of samples.
Table 3.9.1 UNCW AEL evaluation for subbasin 03-06-22
Station
Dissolved Oxygen
Field Turbidity
Chlorophyll a
Fecal Coliform
Nitrate
Total
Phosphorus
SAR
P/G
G
G
F
P
G
GS
P/P
G
G
P
G
G
PB
F/G
G
F
P
F
F
LRC
G/G
G
G
G
P
G
ROC
G/G
G
G
G
P
G
82
Figure 3.9.1 Dissolved Oxygen concentrations (mg/L) at GS and SAR during 2005.
The dashed line shows the NC State swampwater standard of 4.0 mg/L.
14
12
Dissolved Oxygen (mg/L)
GS
10
SAR
8
6
4
2
0
JAN
FEB MAR APR MAY JUN
JUL AUG SEP OCT NOV DEC
Figure 3.9.2 Fecal Coliform Bacteria concentrations (CFU/100mL) at GS and PB
during 2005. The dashed line is the NC State Standard for human contact of 200
cfu/100mL.
1,000
Fecal Coliform Bacteria (cfu)
900
800
GS
700
PB
600
500
400
300
200
100
0
JAN
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
83
Figure 3.9.3 Nitrate-N concentrations (g/L) at SAR, LRC and ROC during 2005. The
dashed line represents the UNCW AEL suggested threshold for good water quality.
1,000
900
SAR
800
LRC
Nitrate (mg/L)
700
ROC
600
500
400
300
200
100
0
JAN
FEB
MAR APR MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
84
3.10 Cape Fear River Subbasin 03-06-23
Location:
Area near Burgaw and Angola swamp
Counties:
Pender
Waterbodies:
Northeast Cape Fear River,Burgaw Creek
Municipalities:
Burgaw
NPDES Dischargers: 7 @ 3.8 million gallons per day
Concentrated Swine Operations: 52
LCFRP monitoring stations (DWQ #):
ANC (69), BCRR (82), BC117 (83), NCF117 (84), NCF6 (85)
DWQ monitoring stations:
BCRR
NCF117
BC117
ANC
NCF117
NCF6
85
This subbasin is located in the outer coastal plain where many streams are slow flowing
blackwater streams that often dry up during the summer months. Most of the watershed is
forested with some agriculture and increasing human development.
The CFR Basinwide Water Quality Plan lists the following ratings for this subbasin:
Aquatic Life
Supporting
Not Rated
Impaired
Not Rated
No Data
Not Rated
73.8 freshwater miles
36.8 freshwater miles
23.4 freshwater miles
8.3 freshwater miles
233.2 freshwater miles
1.0 saltwater acre
Recreation
Supporting
Supporting
Not Rated
No Data
39.5 freshwater miles
1.0 saltwater acre
11.6 freshwater miles
324.5 freshwater miles
Lower Cape Fear River Program Assessment
Data collection: NCF117 & NCF6 since June 1995, others from February 1996
Sampling relevance: point and non-point source dischargers
ANC - Angola Creek
BC117 - Burgaw Canal at US 117
86
NCF117 - Northeast Cape Fear River at
at US117
This subbasin had extensive Dissolved Oxygen problems with BC117 the only site having a
good water quality status when using the 5.0 mg/L standard (Table 3.10.1). All other sites,
ANC, BCRR, NCF117, NCF6 and SC-CH, had a poor water quality status. Using the
swampwater standard of 4.0 mg/L, BC117 and NCF6 had good water quality status and SCCH had a fair status with 17% of samples below the standard. ANC, BCRR, and NC117 had
poor water quality status with sub-standard samples 50%, 42% and 33% of the time,
respectively. Dissolved Oxygen levels for ANC, BCRR and NCF117 are seen in Figure 3.10.1.
All sites in this subbasin had good water quality status for Chlorophyll a and Field Turbidity
(Table 3.10.1). Means for 2005 were well below the standards of 40 g/L and 50 NTU.
For Fecal Coliform Bacteria, NCF117, NCF6 and SC-CH had a good water quality status
(Table 3.10.1). ANC had a fair status, exceeding the human contact standard 25% of the time.
BC117 and BCRR had a poor water quality status, exceeding the standard 42% of the time.
Fecal coliform bacteria concentrations for BCRR and BC117 are shown in Figure 3.10.3.
Nutrient loading of Nitrate and Total Phosphorus was problematic at BC117 which had a poor
water quality status for both (Table 3.10.1, Figure 3.10.3). BC117 had the highest Nitrate and
TP levels seen in the LCFRP system. These levels were far above the concentrations known
to lead to algal bloom formation, bacterial increases and increased biochemical oxygen
demand (BOD) in blackwater streams (Mallin et al. 2001, Mallin et al. 2002).
Table 3.10.1 UNCW AEL evaluation for subbasin 03-06-23
Station
Dissolved Oxygen
Field Turbidity
Chlorophyll a
Fecal Coliform
Nitrate
Total
Phosphorus
ANC
P/P
G
G
F
G
G
BC117
G/G
G
G
P
P
P
BCRR
P/P
G
G
P
F
G
NCF117
P/P
G
G
G
G
G
NCF6
P/G
G
G
G
G
G
SC-CH
P/F
G
G
G
na
na
87
Figure 3.10.1 Dissolved Oxygen concentrations (mg/L) for 2005. The dashed line shows
NC State swampwater standard of 4.0 mg/L.
14
ANC
BCRR
Dissolved Oxygen (mg/L)
12
NCF117
10
8
6
4
2
0
JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC
Figure 3.10.2 Fecal Coliform Bacteria concentrations (CFU/100mL) at BC117 and BCRR
during 2005. The dashed line shows the NC State Standard for human contact waters of 200
CFU/100mL.
Fecal Coliform Bacteria (CFU/100 mL)
800
700
600
BC117
BCRR
500
400
300
200
100
0
JAN
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
88
Figure 3.10.3 Nitrate and Total Phosphorus concentrations (g/L) at BC117 during 2005.
10,000
Nitrate
2,500
TP
9,000
2,000
Nitrate (mg/L)
8,000
7,000
1,500
6,000
5,000
1,000
4,000
3,000
500
2,000
1,000
0
0
JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC
Total Phosphorus (mg/L)
11,000
89
3.12 References Cited
Mallin, M.A., L.B. Cahoon, D.C. Parsons and S.H. Ensign. 2001. Effect of
nitrogen and phosphorus loading on plankton in Coastal Plain blackwater
streams. Journal of Freshwater Ecology 16:455-466.
Mallin, M.A., L.B. Cahoon, M.R. McIver and S.H. Ensign. 2002. Seeking
science-based nutrient standards for coastal blackwater stream systems.
Report No. 341. Water Resources Research Institute of the University of
North Carolina, Raleigh, N.C.
Mallin, M. A., M.R. McIver, S.H. Ensign and L.B. Cahoon. 2004. Photosynthetic
and heterotrophic impacts of nutrient loading to blackwater streams.
Ecological Applications14: 823-838.
NCDENR-DWQ (North Carolina Department of Environment and Natural
Resources-Division of Water Quality), Cape Fear River Basinwide Water
Quality Plan. July 2000, Raleigh, N.C.
NCDENR-DWQ (North Carolina Department of Environment and Natural
Resources-Division of Water Quality), Cape Fear River Basinwide Water
Quality Plan. October 2005, Raleigh, N.C.