HomeMy WebLinkAboutProgress Report_1_January_2008COASTAL PLANNING & ENGINEERING OF NORTH CAROLINA, INC.
NEW HANOVER COUNTY WATER QUALITY MONITORING PROGRAM
FIRST PROGRESS REPORT
Prepared by:
Coastal Planning & Engineering of North Carolina, Inc.
Marine Scientist: Brad Rosov, M.Sc.
Prepared For:
New Hanover County, North Carolina
Recommended Citation: Rosov, B., 2008. New Hanover County Water Quality Monitoring
Program: First Progress Report. New Hanover County, North Carolina: Coastal Planning &
Engineering of North Carolina, Inc. 15p.
January 2008
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COASTAL PLANNING & ENGINEERING OF NORTH CAROLINA, INC.
NEW HANOVER COUNTY WATER QUALITY MONITORING PROGRAM
FIRST PROGRESS REPORT
Table of Contents
Introduction........................................................................................................................................1
Methods..............................................................................................................................................5
Physical Parameters........................................................................................................................5
Chemical and Biological Parameters..............................................................................................5
Results................................................................................................................................................5
Barnards Creek................................................................................................................................6
Futch Creek.....................................................................................................................................6
Lords Creek.....................................................................................................................................8
Motts Creek.....................................................................................................................................9
Pages Creek.....................................................................................................................................10
Prince Georges................................................................................................................................11
Smith Creek....................................................................................................................................12
Discussion..........................................................................................................................................13
Literature Cited..................................................................................................................................15
List of Figures
Figure No.
1 Map of New Hanover County and watersheds included in this study..............................2
List of Tables
Table No.
1 List of Sampling Sites.......................................................................................................1
2 North Carolina Water Quality Standards..........................................................................4
3 Single sample standards for Enterococci as determined by the US EPA.........................4
4 Single sample standards for Enterococci as determined by the NC DENR Recreational
Water Quality Program.....................................................................................................4
List of Appendices
Appendix No.
A Maps of the watersheds and sampling sites
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COASTAL PLANNING & ENGINEERING OF NORTH CAROLINA, INC.
INTRODUCTION
The creeks in New Hanover County, North Carolina provide a wide range of recreational
activities for thousands of local citizens and visiting tourists each year. Protection of the water
quality within these creeks is a high priority of New Hanover County (County). As growth and
development continue within the City of Wilmington and the County, water quality has been
increasingly threatened due to many factors including aging infrastructure, increased impervious
surface area and subsequent stormwater runoff. To address these issues, the County has
administered a long-standing water quality monitoring program since 1993 designed to assess the
water quality within the creeks located within the County.
New Hanover County signed a contract with Coastal Planning & Engineering of North Carolina,
Inc. in October 2007 to perform a water quality monitoring project within seven tidal creeks
between the months of November 2007 and June 2008. The creeks included in this study are
Pages and Futch Creek, which drain into the Intracoastal Waterway (ICW) and Lords, Motts,
Barnards, Smith, and Prince Georges Creek, which drain into the Cape Fear River. As listed in
Table 1 and displayed in Figure 1, a total of 22 sampling stations have been established for this
project. Fifteen of the 22 sampling sites were previously monitored by the University of North
Carolina at Wilmington. This historical data will be available for further analysis of trends within
and between sites and will be incorporated into the Final Report.
Table 1. List of Sampling Sites
Creek Name Site Name Site Code Latitude Longitude
Motts Creek Carolina Beach Road MOT-CBR 34° 08.610 77° 53.830
Motts Creek Normandy Drive MOT-ND 34° 08.373 77° 54.580
Motts Creek River Road MOT-RR 34° 07.752 77° 54.966
Lords Creek River Road LC-RR 34° 05.185 77° 55.275
Barnards Creek Carolina Beach Road BC-CBR 34° 09.522 77° 54.712
Barnards Creek River Road BC-RR 34° 09.525 77° 56.281
Smith Creek Castle Hayne Road SC-CH 34° 15.541 77° 56.325
Smith Creek 23rd Street SC-23 34° 15.472 77° 55.178
Smith Creek Candlewood Drive SC-CD 34° 17.438 77° 51.332
Smith Creek North Kerr SC-NK 34° 15.744 77° 53.256
Smith Creek Gordon Road SC-GR 34° 16.639 77° 52.037
Prince Georges Creek Marathon Landing PG-ML 34° 21.088 77° 55.349
Prince Georges Creek Castle Hayne Road PG-CH 34° 20.675 77° 54.217
Prince Georges Creek North College PG-NC 34° 20.331 77° 53.607
Futch Creek 4 FC-4 34° 18.068 77° 44.760
Futch Creek 6 FC-6 34° 18.178 77° 45.038
Futch Creek 8 FC-8 34° 18.25 77° 45.222
Futch Creek 13 FC-13 34° 18.214 77° 45.451
Futch Creek Foy Branch FC-FOY 34° 18.405 77° 45.358
Pages Creek Mouth PC-M 34° 16.209 77° 46.270
Pages Creek Bayshore Drive Down Stream PC-BDDS 34° 16.685 77° 47.673
Pages Creek Bayshore Drive Up Stream PC-BDUS 34° 16.623 77° 48.104
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Figure 1: Map of New Hanover County and watersheds included in this study
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COASTAL PLANNING & ENGINEERING OF NORTH CAROLINA, INC.
The State of North Carolina has employed a series of classifications that apply to all waters in
the State including streams, rivers, and lakes (NC Administrative Code, section 15A NCAC 2B
.0200). These classifications are each meant to protect water bodies certain specified uses, such
as aquatic life survival and reproduction, secondary recreation, primary recreation, shellfishing,
and water supply. The classifications that apply to the creeks examined in this study are:
C Sw: Freshwater that is protected for aquatic life and secondary recreation uses. The
“Sw” supplemental classification indicates that these are swamp waters, and so are likely
to have lower dissolved oxygen and pH than non-swamp streams due to natural
conditions. However, a majority of the sites, including Lords Creek, Motts Creek,
Barnards Creek, Smith Creek, and Prince Georges Creek, designated as C Sw by the
State, are tidally influenced and have a brackish salinity range.
SA: Saline waterbodies that are protected for shellfishing uses. This use requires a more
stringent standard for fecal coliform. Protection for this use is in addition to protections
for the uses specified by the “lower” classifications of SC and SB, which include aquatic
life, secondary recreation, and primary recreation. This designation applies to Futch
Creek and Pages Creek.
Physical, chemical, and biological water quality monitoring data are currently being collected for
this study. Physical parameters include temperature, salinity, conductivity, pH, turbidity, and
dissolved oxygen. Chemical parameters monitored in this study include orthophosphate and
nitrate/nitrite. Biological parameters include chlorophyll-a and two suites of fecal indicator
bacteria: Enterococci and fecal coliform bacteria. Due to limited funding, fecal coliform
samples were only collected from sampling sites located within Futch Creek and Pages Creek.
Fecal coliform bacteria have been collected within these two watersheds in recent years. By
continuing the collection of this bacteria indicator, a long term analysis of fecal coliform levels
within these watersheds will be possible.
Standards
Water quality standards have been established legislatively for a number of these parameters
(Table 2). Many of the water quality standards are described in the NC Administrative Code,
section 15A NCAC 2H .0100. The water quality standards for Enterococci bacteria are
described by the US EPA (US EPA, 1986) and in the NC Administrative Code, section 15A
NCAC 18A .3402. The US EPA standards for Enterococci bacteria are based on incidents of
gastrointestinal illness following contact with bathing waters. Single sample maximum
allowable Enterococci density is 104 CFU/100ml, 158 CFU/100ml, 276 CFU/100ml, and 501
CFU/100ml for designated beach areas, swimming areas with moderate to full body contact,
lightly used full body contact swimming areas, and infrequently used full body contact
swimming areas, respectively (Table 3). When at least five samples are collected within a 30
day period, the US EPA recommends utilizing a geometric mean standard of 35 CFU/100ml.
The North Carolina Recreational Water Quality Program (RWQ) adopted similar standards for
Enterococci bacteria, also determined by the frequency of swimming activity. As defined by
RWQ, Tier I swimming areas are used daily during the swimming season, Tier II swimming
areas are used three days a week during the swimming season, and Tier III swimming areas are
used on average 4 days a month during the swimming season. Single sample standards for Tiers
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I, II, and III are 104 CFU/100ml, 276 CFU/100ml, and 500 CFU/100ml, respectively (Table 4).
A geometric mean of 35 CFU/100ml within Tier I swimming areas may also be utilized if at
least five samples are collected within 30 days. The creeks included in this study have not been
designated within the RWQ tier system and therefore do not have Enterococci standards ascribed
to them.
Table 2. North Carolina Water Quality Standards
Parameter Standard for SA Waters Standard for C Sw Waters
Dissolved Oxygen 5.0 mg/L 4.0 mg/La
Turbidity 25 NTU 50 NTU
pH 6.8-8.5 6.0-9.0b
Chlorophyll-a 40.0 mg/L 40.0 mg/L
Fecal Coliform Geometric Mean (5 samples within
30 days) <14 CFU/100ml; single
sample <43 CFU/100ml
Geometric Mean (5 samples within
30 days) <200 CFU/100ml; single
sample <400 CFU/100ml
Enterococci Geometric Mean (5 samples within
30 days) <35 CFU/100mlc
Geometric Mean (5 samples within
30 days) <35 CFU/100mlc
a C Sw waters may have lower values caused by natural conditions
b For swamp streams, pH may be as low as 4.3 if caused by natural conditions
c Single sample standards to be determined by New Hanover County based on the tiered system employed by US
EPA or NC DENR Recreational Water Quality Program
Table 3. Single sample standards for Enterococci as determined by the US EPA
Single sample maximum
Designated beach areas < 104 CFU/100 ml
Swimming areas with moderate full body contact < 158 CFU/100 ml
Lightly used full body contact swimming areas < 276 CFU/100 ml
Infrequently used full body contact swimming areas < 501 CFU/100 ml
Table 4. Single sample standards for Enterococci as determined by the NC DENR Recreational
Water Quality Program
Single sample maximum
Tier I, swimming areas used daily during the
swimming season
<104 CFU/100 ml
Tier II, swimming areas used three days a week
during the swimming season
<276 CFU/100 ml
Tier III, swimming areas used on average four days
a month during the swimming season
<500 CFU/100 ml
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COASTAL PLANNING & ENGINEERING OF NORTH CAROLINA, INC.
METHODS
The seven creeks included in this study were selected by County staff and individual sampling
sites were selected by County staff in consultation with Coastal Planning & Engineering of North
Carolina, Inc. These seven creeks are primarily located in the unincorporated portion of New
Hanover County. Sampling sites were accessed from land, generally near a bridge or culvert
crossing, or by boat. Each site was sampled one time per month during a high ebb tide. Tides
were determined utilizing the National Oceanic and Atmospheric Administration’s (NOAA)
Tides and Currents website (http://tidesandcurrents.noaa.gov/).
Due to time constraints, monthly sampling events were conducted on three subsequent days each
month. Lords Creek, Motts Creek, and Barnards Creek were visited on the first sampling day
while Smith Creek and Prince Georges Creek were visited the second day. Futch Creek and
Pages Creek were visited on the third day. Rainfall totals for the 24 hours prior to each sampling
event were obtained from observations recorded at Wilmington International Airport as reported
by NOAA’s National Weather Service web site (http://www.srh.noaa.gov/data/RAH/RTPRAH).
Physical Parameters
All physical measurements (temperature, salinity, conductivity, turbidity, dissolved oxygen, and
pH) were taken in situ utilizing a 6820 YSI Multiparameter Water Quality Probe linked to a YSI
650 MDS display unit. The YSI Probe was calibrated each day prior to use. Physical
measurements were taken from the surface at all sites (depth = 0.1m) and near the creek bottom
at sites with depths greater than 0.5m. Following each sampling trip, the YSI Probe was post-
calibrated to ensure physical parameters measured were within an acceptable range.
Chemical and Biological Parameters
Water samples were obtained for the laboratory analysis of chemical (nitrate/nitrite and
orthophosphate) and biological (Enterococci, fecal coliform, and chlorophyll-a) parameters.
These grab samples were collected in sterile bottles during a high ebb tide from the surface at
each site (depth = 0.1m). Trained volunteers from Cape Fear Community College’s Marine
Technology Department assisted Coastal Planning & Engineering of North Carolina, Inc. staff
with the collection of water samples. Water samples were placed on ice immediately following
collection and were delivered in coolers to Tritest Inc. of Wilmington, North Carolina for
analysis. All analyses performed by Tritest, Inc. were conducted utilizing the following standard
EPA approved methods:
Orthophosphate: SM 4500E
Nitrate/Nitrite: EPA 353.2
Chlorophyll-a: SM 10200H
Fecal Coliform: SM 9222D
Enterococcus: EnterolertE
RESULTS
The preliminary results described in this report represent data collected following the first two
months of monitoring (November and December 2007). The results are organized by watershed
and include data summaries displayed by parameter (physical, biological, and chemical).
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Barnards Creek
Both sampling sites within Barnards Creek watershed were monitored on 14 November and 12
December 2007. Generally, physical, chemical and biological parameters indicated good water
quality within these sites. Dissolved oxygen at BC-CBR was relatively low in December, but
within State standards for C Sw waters. Chlorophyll-a did not breach the 40ug/L standard;
however the value of 24.6ug/L at BC-RR in November did approach this limit.
Physical data collected from Barnards Creek
Date
Site
Name
Rainfall
(inches)
Depth
(m)
Temp.
(oC)
Specific
Conductivity
(us/cm)
Salinity
(ppt)
Dissolved
Oxygen
(mg/L)
Dissolved
Oxygen
(%) pH
Turbidity
(NTU)
11/14/07 BC-CBR 0.0 0.1 14.7 214 0.1 8.2 80 6.9 0
11/14/07 BC-CBR 0.0 1.0 13.6 228 0.1 6.0 58 6.9 8
11/14/07 BC-RR 0.0 0.1 16.2 26603 20.0 8.1 92 7.7 2
11/14/07 BC-RR 0.0 1.8 16.2 26661 20.1 8.1 93 7.7 2
12/12/07 BC-CBR 0.0 0.1 16.0 200 0.1 4.9 50 6.8 0
12/12/07 BC-CBR 0.0 1.0 14.2 197 0.1 5.1 52 6.7 4
12/12/07 BC-RR 0.0 0.1 14.8 29952 23.6 7.7 87 7.7 9
12/12/07 BC-RR 0.0 2.2 14.8 30167 23.8 7.7 88 7.7 12
Biological data collected from Barnards Creek
Date
Site
Name
Rainfall
(inches)
Previous
Depth
(m)
Enterococci
(CFU/100ml
Chlorophyll-a
(ug/L)
11/14/07 BC-CBR 0.0 0.1 88 1.0
11/14/07 BC-RR 0.0 0.1 38 24.6
12/12/07 BC-CBR 0.0 0.1 43 5.34
12/12/07 BC-RR 0.0 0.1 135 4.67
Chemical data collected from Barnards Creek
Date
Site
Name
Rainfall
(inches)
Previous
Depth
(m)
Nitrate/Nitrite
(mg/L)
Orthophosphate
(mg/L)
11/14/07 BC-CBR 0.0 0.1 0.12 0.01
11/14/07 BC-RR 0.0 0.1 0.36 0.05
12/12/07 BC-CBR 0.0 0.1 0.03 0.23
12/12/07 BC-RR 0.0 0.1 0.36 0.05
Futch Creek
Five sampling sites within Futch Creek were monitored on 16 November and 14 December
2007. Fecal coliform counts were extremely high at all sites in November. It is important to
note that a significant rainfall (0.4 inches) was measured within 24 hours of sampling in
November. Enterococci counts were also higher at three of the five sampling sites in November
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compared to December. Despite these high bacteria levels, chlorophyll-a, dissolved oxygen,
turbidity, nitrate/nitrite, and orthophosphate values were well within their respective standards
during this period at all sites.
Physical data collected from Futch Creek
Date
Site
Name
Rainfall
(inches)
Depth
(m)
Temp.
(oC)
Specific
Conductivity
(us/cm)
Salinity
(ppt)
Dissolved
Oxygen
(mg/L)
Dissolved
Oxygen
(%) pH
Turbidity
(NTU)
11/16/07 FC-13 0.35 0.1 13.3 37644 31.9 8.3 97 8.0 0
11/16/07 FC-13 0.35 0.6 13.9 41705 34.8 8.3 98 8.1 4
11/16/07 FC-4 0.35 0.1 14.3 43467 36.2 8.0 98 8.2 0
11/16/07 FC-4 0.35 0.4 14.4 43640 36.2 8.3 101 8.2 0
11/16/07 FC-6 0.35 0.1 13.9 42932 35.6 8.1 98 8.1 0
11/16/07 FC-6 0.35 0.8 14.0 43048 36.0 8.2 100 8.1 0
11/16/07 FC-8 0.35 0.1 13.9 42690 35.8 8.1 97 8.1 0
11/16/07 FC-8 0.35 0.4 14.0 42782 35.8 8.2 98 8.1 0
11/16/07 FC-FOY 0.35 0.1 13.9 41919 35.1 8.3 100 8.1 0
11/16/07 FC-FOY 0.35 0.6 14.0 42592 35.6 8.5 102 8.1 0
12/14/07 FC-13 0.0 0.1 17.2 42912 33.1 6.5 82 8.0 1
12/14/07 FC-13 0.0 0.5 16.8 46333 36.5 6.5 83 8.1 5
12/14/07 FC-4 0.0 0.1 16.4 47880 38.2 6.8 88 8.1 0
12/14/07 FC-4 0.0 2.0 16.3 47885 38.2 7.3 94 8.1 1
12/14/07 FC-6 0.0 0.1 16.4 47880 38.2 6.8 88 8.1 0
12/14/07 FC-6 0.0 1.0 16.5 47735 37.9 7.5 97 8.1 0
12/14/07 FC-8 0.0 0.1 16.6 47072 37.3 6.8 86 8.1 0
12/14/07 FC-8 0.0 0.4 16.5 47184 37.4 6.9 89 8.1 0
12/14/07 FC-FOY 0.0 0.1 16.9 45357 35.5 6.6 85 8.1 0
12/14/07 FC-FOY 0.0 0.5 16.8 46009 36.1 7.0 90 8.1 1
Biological data collected from Futch Creek
Date
Site
Name
Rainfall
(inches)
Depth
(m)
Enterococci
(CFU/100ml
Fecal
Coliform
(CFU/100ml)
Chlorophyll-a
(ug/L)
11/16/07 FC-13 0.35 0.1 25 4400 1.0
11/16/07 FC-4 0.35 0.1 119 3800 1.0
11/16/07 FC-6 0.35 0.1 109 6400 2.1
11/16/07 FC-8 0.35 0.1 23 4800 4.3
11/16/07 FC-FOY 0.35 0.1 98 7000 2.1
12/14/07 FC-13 0.0 0.1 78 200 1.0
12/14/07 FC-4 0.0 0.1 70 50 1.0
12/14/07 FC-6 0.0 0.1 23 50 1.0
12/14/07 FC-8 0.0 0.1 34 100 1.0
12/14/07 FC-FOY 0.0 0.1 80 100 1.0
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Chemical data collected from Futch Creek
Date
Site
Name
Rainfall
(inches)
Depth
(m)
Nitrate/Nitrite
(mg/L)
Orthophosphate
(mg/L)
11/16/07 FC-13 0.35 0.1 0.05 0.01
11/16/07 FC-4 0.35 0.1 0.08 0.01
11/16/07 FC-6 0.35 0.1 0.04 0.01
11/16/07 FC-8 0.35 0.1 0.02 0.01
11/16/07 FC-FOY 0.35 0.1 0.04 0.01
12/14/07 FC-13 0.0 0.1 0.03 0.01
12/14/07 FC-4 0.0 0.1 0.02 0.01
12/14/07 FC-6 0.0 0.1 0.01 0.01
12/14/07 FC-8 0.0 0.1 0.01 0.01
12/14/07 FC-FOY 0.0 0.1 0.01 0.01
Lords Creek
One sampling site was monitored within Lords Creek on 14 November and 12 December 2007.
Dissolved oxygen was extremely low at both the surface and near the bottom during both
sampling events. While turbidity did not exceed the State standard of 50 NTU, the observed
values were higher than expected. Enterococci counts were also elevated during both months.
Physical data collected from Lords Creek
Date
Site
Name
Rainfall
(inches)
Depth
(m)
Temp.
(oC)
Specific
Conductivity
(us/cm)
Salinity
(ppt)
Dissolved
Oxygen
(mg/L)
Dissolved
Oxygen
(%) pH
Turbidity
(NTU)
11/14/07 LC-RR 0.0 0.1 16.5 30011 22.7 8.8 103 7.7 1
11/14/07 LC-RR 0.0 1.4 16.5 30054 22.7 8.8 103 7.7 2
12/12/07 LC-RR 0.0 0.1 16.0 34778 27.0 7.8 93 7.6 24
12/12/07 LC-RR 0.0 1.3 16.0 34849 27.1 7.7 92 7.6 32
Biological data collected from Lords Creek
Date
Site
Name
Rainfall
(inches)
Depth
(m)
Enterococci
(CFU/100ml
Chlorophyll-a
(ug/L)
11/14/07 LC-RR 0.0 0.1 548 7.5
12/12/07 LC-RR 0.0 0.1 158 6.7
Chemical data collected from Lords Creek
Date
Site
Name
Rainfall
(inches)
Depth
(m)
Nitrate/Nitrite
(mg/L)
Orthophosphate
(mg/L)
11/14/07 LC-RR 0.0 0.1 0.31 0.03
12/12/07 LC-RR 0.0 0.1 0.20 0.03
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Motts Creek
Three sampling sites within the Motts Creek watershed were included in this study. Water
quality within these three sites was monitored on 14 November and 12 December 2007.
Dissolved oxygen was poor within MOT-CBR and MOT-ND in December. High levels of
Enterococci bacteria were recorded at MOT-ND during both months. Nutrient levels, turbidity,
pH, and chlorophyll-a were acceptable during both sampling events.
Physical data collected from Motts Creek
Date Site Name
Rainfall
(inches)
Depth
(m)
Temp
(C)
Specific
Conductivity
(us/cm)
Salinity
(ppt)
Dissolved
Oxygen
(mg/L)
Dissolved
Oxygen
(%) pH
Turbidity
(NTU)
11/14/07 MOT-CBR 0.0 0.1 18.5 522 0.3 4.9 52 7.0 16
11/14/07 MOT-ND 0.0 0.1 14.2 447 0.2 6.7 65 7.2 0
11/14/07 MOT-RR 0.0 0.1 16.1 26013 19.5 8.3 94 7.5 0
11/14/07 MOT-RR 0.0 1.2 16.1 26002 19.5 8.3 94 7.5 0
12/12/07 MOT-CBR 0.0 0.1 18.5 508 0.3 3.2 34 6.8 5
12/12/07 MOT-ND 0.0 0.1 16.3 413 0.2 3.2 33 7.0 4
12/12/07 MOT-RR 0.0 0.1 16.0 26137 19.7 6.7 76 7.3 0
12/12/07 MOT-RR 0.0 1.6 16.0 25916 19.5 6.7 76 7.3 2
Biological data collected from Motts Creek
Date Site Name
Rainfall
(inches)
Depth
(m)
Enterococci
(CFU/100ml
Chlorophyll-a
(ug/L)
11/14/07 MOT-CBR 0.0 0.1 56 25.6
11/14/07 MOT-ND 0.0 0.1 1414 6.4
11/14/07 MOT-RR 0.0 0.1 23 1.0
12/12/07 MOT-CBR 0.0 0.1 10 3.3
12/12/07 MOT-ND 0.0 0.1 129 5.3
12/12/07 MOT-RR 0.0 0.1 68 4.0
Chemical data collected from Motts Creek
Date Site Name
Rainfall
(inches)
Depth
(m)
Nitrate/Nitrite
(mg/L)
Orthophosphate
(mg/L)
11/14/07 MOT-CBR 0.0 0.1 0.13 0.01
11/14/07 MOT-ND 0.0 0.1 0.05 0.03
11/14/07 MOT-RR 0.0 0.1 0.29 0.01
12/12/07 MOT-CBR 0.0 0.1 0.04 0.02
12/12/07 MOT-ND 0.0 0.1 0.02 0.01
12/12/07 MOT-RR 0.0 0.1 0.18 0.03
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Pages Creek
Three sampling sites were visited in the Pages Creek watershed on 16 November and 14
December 2007. Dissolved oxygen values recorded from PC-BDUS and PC-BDDS in
December were below the State standard of 5.0mg/L. The fecal coliform levels were extremely
high in November following a significant rainfall. Enterococci levels were elevated in both
November and December. Chlorophyll-a, turbidity, pH, and chemical parameters were within
acceptable ranges.
Physical data collected from Pages Creek
Date Site Name
Rainfall
(inches)
Depth
(m)
Temp.
(oC)
Specific
Conductivity
(us/cm)
Salinity
(ppt)
Dissolved
Oxygen
(mg/L)
Dissolved
Oxygen
(%) pH
Turbidity
(NTU)
11/16/07 PC-BDDS 0.35 0.1 12.6 40790 35.2 7.5 88 8.0 0
11/16/07 PC-BDUS 0.35 0.1 14.5 25139 19.6 6.3 70 7.4 2
11/16/07 PC-M 0.35 0.1 14.1 43188 36.2 7.7 93 8.0 0
11/16/07 PC-M 0.35 1.6 14.1 43301 36.2 7.8 95 8.1 0
12/14/07 PC-BDDS 0.0 0.1 17.5 44825 34.5 4.8 61 7.8 3
12/14/07 PC-BDUS 0.0 0.1 19.0 30794 21.9 4.5 56 7.3 4
12/14/07 PC-M 0.0 0.1 16.7 48166 38.2 7.1 92 8.1 1
12/14/07 PC-M 0.0 1.5 16.7 48146 38.2 7.1 92 8.1 3
Biological data collected from Pages Creek
Date Site Name
Rainfall
(inches)
Depth
(m)
Enterococci
(CFU/100ml
Fecal
Coliform
(CFU/100ml)
Chlorophyll-a
(ug/L)
11/16/07 PC-BDDS 0.35 0.1 548 4200 1.0
11/16/07 PC-BDUS 0.35 0.1 135 7200 1.0
11/16/07 PC-M 035 0.1 70 5600 3.2
12/14/07 PC-BDDS 0.0 0.1 727 700 1.0
12/14/07 PC-BDUS 0.0 0.1 517 500 1.0
12/14/07 PC-M 0.0 1.5 121 50 1.0
Chemical data collected from Pages Creek
Date Site Name
Rainfall
(inches)
Depth
(m)
Nitrate/Nitrite
(mg/L)
Orthophosphate
(mg/L)
11/16/07 PC-BDDS 0.35 0.1 0.04 0.03
11/16/07 PC-BDUS 0.35 0.1 0.04 0.04
11/16/07 PC-M 035 0.1 0.04 0.01
12/14/07 PC-BDDS 0.0 0.1 0.03 0.04
12/14/07 PC-BDUS 0.0 0.1 0.01 0.08
12/14/07 PC-M 0.0 1.5 0.01 0.01
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COASTAL PLANNING & ENGINEERING OF NORTH CAROLINA, INC.
Prince Georges
Three sampling sites were visited in the Prince Georges Creek watershed on 15 November and
13 December 2007. Dissolved oxygen values recorded from PG-NC were well below the State
standard of 4.0mg/L in both November and December. Dissolved oxygen at PG-CH was just
above the acceptable limit in November and below the State standard during December.
Enterococci levels were higher in November following the rain event compared to the values
observed in December. Chlorophyll-a, turbidity, and chemical parameters were within
acceptable ranges.
Physical data collected from Prince Georges Creek
Date
Site
Name
Rainfall
(inches)
Depth
(m)
Temp.
(oC)
Specific
Conductivity
(us/cm)
Salinity
(ppt)
Dissolved
Oxygen
(mg/L)
Dissolved
Oxygen
(%) pH
Turbidity
(NTU)
11/15/07 PG-CH 0.2 0.1 14.0 801 0.5 5.1 49 7.4 0
11/15/07 PG-CH 0.2 1.0 13.9 837 0.5 4.8 46 7.4 4
11/15/07 PG-ML 0.2 0.1 14.5 1934 1.3 6.6 65 6.7 0
11/15/07 PG-NC 0.2 0.1 11.6 138 0.1 1.2 11 6.4 4
11/15/07 PG-NC 0.2 1.3 9.9 133 0.1 0.4 3 6.4 5
12/13/07 PG-CH 0.0 0.1 15.3 757 0.5 4.2 42 7.4 0
12/13/07 PG-CH 0.0 1.2 15.0 742 0.5 3.5 35 7.4 4
12/13/07 PG-ML 0.0 0.1 15.7 844 0.5 6.2 63 6.8 0
12/13/07 PG-NC 0.0 0.1 14.2 162 0.1 3.3 31 6.7 0
12/13/07 PG-NC 0.0 3.2 8.8 147 0.1 0.6 5 6.5 0
Biological data collected from Prince Georges Creek
Date
Site
Name
Rainfall
(inches)
Depth
(m)
Enterococci
(CFU/100ml
Chlorophyll-a
(ug/L)
11/15/07 PG-CH 0.2 0.1 281 3.2
11/15/07 PG-ML 0.2 0.1 378 1.0
11/15/07 PG-NC 0.2 0.1 8 9.6
12/13/07 PG-CH 0.0 0.1 135 4.0
12/13/07 PG-ML 0.0 0.1 57 5.3
12/13/07 PG-NC 0.0 0.1 4 2.7
Chemical data collected from Prince Georges Creek
Date
Site
Name
Rainfall
(inches)
Depth
(m)
Nitrate/Nitrite
(mg/L)
Orthophosphate
(mg/L)
11/15/07 PG-CH 0.2 0.1 0.35 0.04
11/15/07 PG-ML 0.2 0.1 0.05 0.01
11/15/07 PG-NC 0.2 0.1 0.1 0.01
12/13/07 PG-CH 0.0 0.1 0.01 0.07
12/13/07 PG-ML 0.0 0.1 0.05 0.02
12/13/07 PG-NC 0.0 3.2 0.01 0.01
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COASTAL PLANNING & ENGINEERING OF NORTH CAROLINA, INC.
Smith Creek
Five sampling sites were visited in the Smith Creek watershed on 15 November and 13
December 2007. Generally, dissolved oxygen was good at all sites each month with the
exception of low levels observed at SC-GR in December. Enterococci levels were elevated
during both months at all sites with the exception of SC-CH in December. Nitrite/nitrate and
chlorophyll-a levels were relatively high at Smith Creek sites compared to other watersheds
studied in this program, particularly in November.
Physical data collected from Smith Creek
Date
Site
Name
Rainfall
(inches)
Depth
(m)
Temp.
(C)
Specific
Conductivity
(us/cm)
Salinity
(ppt)
Dissolved
Oxygen
(mg/L)
Dissolved
Oxygen
(%) pH
Turbidity
(NTU)
11/15/07 SC-23 0.2 0.1 15.8 15891 11.5 8.5 92 7.5 3
11/15/07 SC-23 0.2 2.4 15.8 16177 11.7 8.4 91 7.6 4
11/15/07 SC-CD 0.2 0.1 15.4 166 0.1 7.9 79 7.2 7
11/15/07 SC-CH 0.2 0.1 16.0 21501 15.9 7.0 78 7.3 4
11/15/07 SC-CH 0.2 1.8 16.0 21762 16.1 6.8 76 7.4 8
11/15/07 SC-GR 0.2 0.1 15.4 191 0.1 6.4 64 7.0 0
11/15/07 SC-NK 0.2 0.1 14.9 8517 6.0 7.7 80 7.0 0
11/15/07 SC-NK 0.2 2.8 14.8 8790 6.2 7.7 80 7.1 0
12/13/07 SC-23 0.0 0.1 15.7 18805 13.8 7.5 82 7.3 1
12/13/07 SC-23 0.0 2.3 15.2 18911 14.1 7.7 84 7.3 1
12/13/07 SC-CD 0.0 0.1 16.6 257 0.2 5.8 59 7.1 0
12/13/07 SC-CH 0.0 0.1 15.1 23625 18.1 7.1 79 7.3 4
12/13/07 SC-CH 0.0 1.8 14.4 24254 18.6 7.2 79 7.4 6
12/13/07 SC-GR 0.0 0.1 16.0 219 0.1 3.8 38 6.8 0
12/13/07 SC-GR 0.0 0.5 15.9 212 0.1 3.3 33 6.8 6
12/13/07 SC-NK 0.0 0.1 16.2 5712 3.8 6.2 64 6.8 0
12/13/07 SC-NK 0.0 2.8 16.2 5802 3.8 6.2 64 6.8 1
Biological data collected from Smith Creek
Date
Site
Name
Rainfall
(inches)
Depth
(m)
Enterococci
(CFU/100ml
Chlorophyll-a
(ug/L)
11/15/07 SC-23 0.2 0.1 238 34.2
11/15/07 SC-CD 0.2 0.1 517 13.9
11/15/07 SC-CH 0.2 0.1 285 3.2
11/15/07 SC-GR 0.2 0.1 250 27.8
11/15/07 SC-NK 0.2 0.1 99 9.6
12/13/07 SC-23 0.0 0.1 1300 6.0
12/13/07 SC-CD 0.0 0.1 1210 1.0
12/13/07 SC-CH 0.0 0.1 11 1.0
12/13/07 SC-GR 0.0 0.1 139 2.0
12/13/07 SC-NK 0.0 0.1 238 1.0
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COASTAL PLANNING & ENGINEERING OF NORTH CAROLINA, INC.
Chemical data collected from Smith Creek
Date
Site
Name
Rainfall
(inches)
Depth
(m)
Nitrate/Nitrite
(mg/L)
Orthophosphate
(mg/L)
11/15/07 SC-23 0.2 0.1 0.25 0.03
11/15/07 SC-CD 0.2 0.1 0.24 0.06
11/15/07 SC-CH 0.2 0.1 0.35 0.04
11/15/07 SC-GR 0.2 0.1 0.07 0.01
11/15/07 SC-NK 0.2 0.1 0.01 0.01
12/13/07 SC-23 0.0 0.1 0.29 0.05
12/13/07 SC-CD 0.0 0.1 0.03 0.01
12/13/07 SC-CH 0.0 0.1 0.41 0.05
12/13/07 SC-GR 0.0 0.1 0.04 0.01
12/13/07 SC-NK 0.0 0.1 0.05 0.01
DISCUSSION
It is not feasible to fully characterize the water quality of the creeks within New Hanover County
after only two months of monitoring, however the data presented in this report will provide the
public and County staff information on the current state of the creeks. Water quality is an
important issue in the region due to the fact that there are many economic and recreational
opportunities that are supported by the aquatic resources in and around these waterways. One of
the greatest threats to water quality in this area is stormwater runoff created by increased
impervious surface coverage (Mallin et al., 2000). Polluted stormwater runoff can have many
adverse effects on plants, fish, animals and people. Excess nutrients can cause algae blooms
while bacteria and other pathogens can wash into swimming areas and create health hazards.
New Hanover County has experienced rapid growth and development over the past several
decades. In 1990, the population within the County was 120,284. By 2006, the population grew
over 50% to 182,591 (U.S. Census Bureau, 2006). Along with this population increase and
subsequent stormwater runoff, numerous septic tanks, aging wastewater infrastructure, and other
factors potentially impact the water quality within the County’s creeks. With this in mind, it is
important to monitor the water quality of these local systems to determine potential impacts to
both human health and ecosystem function.
Algal blooms were not present at any site during the November and December sampling events.
While sometimes problematic in the summer months, algal blooms are less common in the fall
and winter when water temperature decreases. High levels of nutrients along with other physical
conditions may trigger an algal bloom. Algal blooms may be indicated by high chlorophyll-a,
low dissolved oxygen, and elevated pH values. Nitrite/nitrate and orthophosphate levels
observed in this study were relatively low ranging between 0.01-0.41mg/L and 0.01-0.23mg/L,
respectively. Chlorophyll-a levels ranged between 1.0 and 34.2ug/L which was within the
acceptable level of 40ug/L as determined by the State. The pH values were also found to be
within acceptable ranges (6.4 to 8.2). By evaluating these factors together, it was apparent that
no algal blooms were present during either sampling period.
Dissolved oxygen levels at a number of sites were below the State standard of 5.0 ml/L in SA
waters and 4.0 mg/L in C Sw waters. The low dissolved oxygen values observed in MOT-CBR,
14
COASTAL PLANNING & ENGINEERING OF NORTH CAROLINA, INC.
MOT-ND, and SC-GR may have been attributable to recent brush clearing of the right-of-way
adjacent to the creek banks. If any of this plant material entered the creek, dissolved oxygen
would decrease in response to bacterial respiration as the vegetation decomposes. Another factor
influencing the water quality within Motts Creek may be the recent rapid development within the
watershed. Currently, land is being cleared for a new mixed-use development along portions of
the creek. A comparison of historical monitoring data within Motts Creek to the data collected
during this study will help assess potential impacts of construction activity on the water quality
within this watershed. PG-NC also experienced low dissolved oxygen during both months of
monitoring. This site is characterized by very low flow and low pH and is situated in a swamp-
like setting with a shallow, broad channel. Low dissolved oxygen is not unexpected in swamp
environments.
Bacteriological parameters were extremely high in November, particularly within Smith Creek,
Prince Georges Creek, Futch Creek and Pages Creek. Samples were obtained on 15 and 16
November following the first significant rainfall since 25 October, which may have influenced
these high counts. Stormwater runoff into these watersheds may have carried an increased load
of fecal coliform and Enterococci due to the drought conditions prior to the rain event on the
16th. Although fecal indicator bacteria are not pathogenic themselves, they correlate well with
levels of illness in swimmers, in particularly Enterococci (US EPA 1986). The US EPA has
determined that the Enterococci provide the best correlation between swimming-associated
gastrointestinal illnesses (US EPA, 1984, US EPA, 1986). As a result of the Beaches
Environmental Assessment and Coastal Health (BEACH) Act of 2000, State governments were
mandated by the US EPA to adopt Enterococci bacteria as an indicator of human health risk in
coastal recreational waters. Due to their ability to survive longer in salt water, Enterococci is
considered to be more conservative indicator of pathogenic contaminants compared to fecal
coliform (Hanes and Fragela, 1967; del Mar Lleò et al., 2005). Other research supports the
functionality of utilizing either or both indicators to test for risks associated with contact with
water (Harrington and Cahoon, 2007).
Additional data collected through the course of this eight month study will help provide insight
as to the state of the water quality within the creeks in New Hanover County. In order to fully
assess the water quality, it will be important to continue monitoring through the summer months
when recreational activity increases within the creeks and water quality often diminishes. Long-
term monitoring can help distinguish seasonal variation in the measured parameters.
15
COASTAL PLANNING & ENGINEERING OF NORTH CAROLINA, INC.
LITERATURE CITED
del Mar Lleò, M.; Bonato, B.; Benedetti, D.; and Canepari, P., 2005. Survival of enterococcal
species in aquatic environments. FEMS Microbiology Ecology, 5 4:189-196.
Hanes, N.B.; and Frangela, R., 1967. Effect of seawater concentration on survival of indicator
bacteria. Journal of the Water Pollution Control Federation 39:97-104.
Harrington R.N. and Cahoon, L.B., 2007. Fecal indicator bacteria in the water and sediments of
local boat ramps. pp. 68-80, within Environmental Quality of Wilmington and New Hanover
County Watersheds 2005-2006, CMS Report 07-01, UNCW Center for Marine Science
Research.
Mallin, M.A.; Williams, K.E.; Esham, C.E.; and Lowe, P.R., 2000. Effect of human
development on bacteriological water quality in coastal watersheds. Ecological Applications
10:1047-1056.
U.S. Census Bureau, 2006 Population Estimates, Census 2000, 1990 Census
U.S. Environmental Protection Agency. 1984. Health effects criteria for fresh recreational
waters. EPA-600/1-84-004, U.S. Environmental Protection Agency, Washington, D.C.
U.S. Environmental Protection Agency. 1986. Ambient Water Quality Criteria for Bacteria-
1986. EPA-440/5/84-002, U.S. Environmental Protection Agency, Washington, D.C
COASTAL PLANNING & ENGINEERING OF NORTH CAROLINA, INC.
APPENDIX A
Maps of Watersheds and Sampling Sites