I-44_Ellerbe Creek Data Review_FINAL

Ellerbe Creek Data Review
Monitoring Conducted by the City of Durham
Monitoring Overview
Ellerbe Creek is a watershed located in the northern part of the City of Durham and covers an area of
approximately 37 square miles. The watershed begins in downtown Durham, just north of the Durham
Freeway, and flows Northeast to where it discharges into upper Falls Lake. Ellerbe Creek has been
monitored by the City of Durham for over 20 years. Surface water quality, sediment quality, biological
monitoring, and hydrology data at sampling sites located in the Ellerbe Creek watershed were generally
collected by the City as part of, the ambient monitoring program (AMP), and special studies. The City's
AMP consists of water chemistry monitoring collected monthly and biological monitoring collected
yearly. Special studies were generally short term (<1 year) planned studies that provided a variety of
environmental data. Appendix A. Summary Table for Data Collected in Ellerbe Creek includes a summary
table of all sites and the parameters collected in the Ellerbe Creek watershed that have been monitored
by the City since 2002.
Project and Special Study Descriptions
Below is a detailed list of all the programs and special studies conducted by the City of Durham that
generated data collected in the Ellerbe Creek watershed.
Ambient Monitoring Program
Purpose/Objectives
The AMP characterizes watersheds located in the City of Durham through monitoring of water
chemistry, benthic macroinvertebrate community, and stream hydrology of selected streams. Streams
selected for monitoring are fixed locations strategically located inside or just outside the City limits. Sites
are monitored by the City of Durham Water Quality Unit (WQU) staff monthly and are on an even and
odd year sampling rotation for particular watersheds. Therefore, the majority of sites are sampled every
other year. Data from the AMP can be used to track trends in water quality, identify pollution problem
areas and evaluate water quality impacts of urban stormwater on area streams
Ambient water chemistry monitoring data included in this report dates back to 2004. Although data
were collected before 2004, inconsistent protocols during that time made comparisons of pre-2004 data
to post-2004 data impractical.
Brief Methodology
Sites that are being actively monitored were typically visited monthly for water quality sampling. Water
chemistry samples are collected and physical parameters are measured following Ambient Monitoring
standard protocols and are typically analyzed at the South Durham Water Reclamation Facility (SDWRF).
All monitoring dates are pre -scheduled to eliminate bias in sampling conditions.
There are three different types AMP sampling sites: nutrient loading sites, comprehensive sites, and
fecal only sites. Nutrient loading sites are a core group of AMP sites that are sampled for all
comprehensive parameters every year, and are utilized for the calculation of pollutant loads or the
evaluation of specific pollution sources. Comprehensive sample sites are sites where all of the
requested parameters for the AMP are collected. Fecal only sites are sites where only fecal coliform is
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analyzed. Depending on AMP goals at the time, parameters may have been added or removed from
the comprehensive site parameter list. At the time this report was written, there were no sites being
sampled that were categorized as fecal only sites, only nutrient loading sites and comprehensive sites
were being sampled.
In situ water chemistry parameters are collected at all AMP sites and include: water temperature,
conductivity, turbidity, dissolved oxygen, and pH. The parameters evaluated at fecal only sites (fecal
coliform and in situ water chemistry parameters) have stayed consistent since 2004. The parameters
evaluated at the comprehensive and nutrient loading sites have varied slightly since 2004. In 2004,
comprehensive water quality monitoring sites were generally evaluated for in situ water chemistry
parameters, nutrients (ammonia, nitrate/nitrite, total Kjeldahl nitrogen (TKN), and total phosphorus),
metals (dissolved zinc and total and dissolved copper), total suspended solids (TSS), and biochemical
oxygen demand (BOD). In 2005, calcium and magnesium were added to calculate hardness to evaluate
dissolved metals toxicity according to the EPA's "National Recommended Water Quality Criteria" (EPA,
2005). In 2009, hardness was added to the list of comprehensive site analytes to evaluate whether there
was a need to continue monitoring for calcium and magnesium. Finally, in 2016 dissolved zinc was
added to the list of comprehensive site analytes due to continuous instances of increased zinc levels at a
handful of AMP sites.
Additional site -specific parameters may have been measured or sampled to evaluate other pollutant
indicators. On occasion, a site may have been sampled for ambient water chemistry concurrently with a
special study.
Ambient Monitoring in the Watershed
Since consistent monitoring commenced in 2004, 13 sites in the Ellerbe Creek watershed have been
monitored as part of the AMP. Nine of the 13 ambient sampling sites were actively monitored at the
generation of this report.
Ambient Benthic Macroinvertebrate Sampling and Habitat Assessments
Purpose/Objective
Benthic macroinvertebrate sampling and habitat assessment were added as part of the AMP to provide
further information about the impacts of water quality, instream habitat, and hydrology on instream
biological communities. There is great diversity in terms of the number of benthic taxa found in eastern
North American freshwaters, and consequently great diversity in life histories and sensitivities to
pollutants and other stressors. Because of these characteristics, macroinvertebrate communities were
used to provide an assessment of the sum of acute and chronic effects on biological communities from
water quality, hydrology, and habitat conditions within a stream.
The WQU has conducted biological assessments utilizing benthic macroinvertebrates since 1999 at
monitoring sites in the Ellerbe Creek watershed. However, it was not until 2003 that the data
collected was reliable enough to be used in reporting. This was mainly due to the early practices of
collection and identification. All data were collected during the summer months, except in 2009 when
sampling strategies were being evaluated and switched to winter/spring sampling.
Brief Methodology
Originally, benthic macroinvertebrate sampling was conducted in-house by WQU staff, however, in
recent years, benthic sampling and taxonomic identification has been conducted by a contractor, with
the assistance of WQU staff. All staff and contracted helpers follow the procedures outlined in the Draft
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Standard Operating Procedures for Benthic Macroinvertebrate Community Monitoring. In general, the
procedures involved in benthic macroinvertebrate sampling include:
• Field collection of benthic macroinvertebrate samples;
• completion of instream habitat assessments;
• taxonomic identification of samples; and
• analysis of results.
While the terms and methodologies are largely similar to those used by the North Carolina Department
of Environmental Quality (NCDEQ), the WQU has different site criteria for determining the applicability
of methods for certain sampling locations within the Triassic Basins ecoregion.
Benthic Monitoring in the Watershed
Benthic Macroinvertebrate sampling has been conducted at six sampling sites in the Ellerbe Creek
watershed, EL1.9EC, EL5.5GC, EL5.6EC, EL7.1EC, EL7.9EC, and EL8.2EC. EL1.9EC, EL5.5GC, EL5.6EC, and
EL7.1EC were actively monitored benthic sites at the time when this report was written, where samples
are collected every other year. EL7.9EC was dropped in 2017 and EL8.2EC was dropped in 2012.
Water Quality Investigations
Purpose/Objective
Water quality investigations are conducted to follow up on concerns and complaints related to illicit
discharges and connections within the City of Durham City limits. The goal of the water quality
investigations is specifically to find and eliminate discharges of non-stormwater substances to the
drainage system and/or surface waters. These investigations are initiated all throughout the year and
are initiated based on reports of possible pollution from a variety of sources.
Brief Methodology
Investigations are reported to the water quality group through a variety of sources, including
complainants calling the pollution prevention hotline, other city staff members notifying the water
quality group of an issue, or lab results that indicate chemical levels are outside of a normal range.
Water Quality Investigations Conducted in the Watershed
Water quality investigations have been conducted inside the City of Durham City limits since 1993. As
the Ellerbe Creek watershed is located in a central part of Durham near downtown, there have been
numerous investigations conducted in this watershed. Also, this part of the City of Durham has both
older infrastructure and higher levels of new and re -development in recent years, causing the number of
investigations to increase in Ellerbe Creek. Typical types of investigations conducted in the Ellerbe Creek
watershed include, but are not limited to, sanitary sewer overflows, construction related discharges
(sediment, concrete, paint, etc.), cooking grease, trash, and yard waste.
Outfall Screening
Purpose/Objective
The City's dry weather outfall screening program was implemented to detect, trace, and eliminate
sources of illicit discharges. The WQU usually conducts outfall screenings during two sessions each year:
1) during the fall -winter months (October through March) and 2) during the summer months (July
through August). Formal dry weather screening during the fall -winter months has been conducted each
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year since 2008. Screening during the summer months began in 2014. Over the past five years, dry
weather screening has been conducted by the City in twelve different watersheds
The City also conducts a separate, year-round program of dry weather screening of industrial outfalls.
That program targets outfalls associated with industrial facilities. The results of industrial dry weather
outfall screening are reported in the City's NPDES Annual Report.
Brief Methodology
Field staff follow the best management practices and procedures for outfall screening and monitoring.
When flow is observed at an outfall, chemical properties are measured using a pH/conductivity pen, YSI
ODO meter, and CHEMetrics kit. If any of the tested parameters are considered to be outside of the
normal range, standard IDDE techniques are followed in an attempt to determine a source of the
discharge, and a Water Quality Investigation is usually initiated.
Outfall Screening Conducted in the Watershed
Outfalls located in the Ellerbe Creek watershed have been monitored in the 2011— 2012, 2015 — 2016,
2016 — 2017, and the 2019 - 2020 outfall screening seasons.
Special Studies
Sampling sites in the Ellerbe Creek watershed have been utilized for 14 special studies, that have
focused on a wide variety of topics. A brief description of each study is included below.
Air Conditioning Coil Cleaning Study
The purpose of the Air Conditioning Coil Cleaning Study (AC Coil Study) was to evaluate the wastewater
generated from the process of cleaning air conditioning units and to quantify pollutant loads to the
City's MS4 and downstream surface waters. To evaluate the wastewater and quantify pollutant loads,
wastewater composite samples were collected at three sites (407 Morris St, 423 Morris St, and 404 Hunt
St) and analyzed for aluminum, cadmium, copper, zinc, ammonia nitrogen, nitrate + nitrite, total
Kjeldahl nitrogen (TKN), total nitrogen, total phosphorus, methylene blue active substances (MBAS),
biochemical oxygen demand (BOD), and total suspended solids (TSS). This study found that the
concentrations of total cadmium, total copper, total zinc, total nitrogen, BOD, and TSS measured in the
HVAC coil cleaning wastewater were higher than average concentrations in untreated domestic
wastewater.
Ambient Chemistry Split Study
The Ambient Split Study is a reoccurring Quality Assurance (QA) study conducted to determine inter -
laboratory variability by reviewing the comparative results on analysis conducted by multiple
laboratories. This study also helps to provide additional QA to Water Quality group data. This study is
conducted by sending identical samples to multiple laboratories to have the same pre -selected
parameters analyzed. The 2010 and 2017 studies collected samples as a "true split" and the 2008 and
2012 studies collected samples "concurrently". A "true split" sample is done by collecting the total
needed sample volume and pulling aliquots for each laboratory. A sample collected "concurrently" is
done by having two field staff members collect a sample at the surface by direct dip simultaneously. The
sites selected for each of the Split Studies varies depending on which ambient sites are being sampled at
the time and they are chosen to give a range of relative concentration conditions based on data from
previous years. Ambient Split Studies samples were collected at eight AMP sites within the Ellerbe Creek
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Watershed, EL1.9EC, EL5.5GC, EL5.6EC, EL7.ISEC, EL7.9EC, EL8.1GC, and EL10.7EC in 2010 and at
EL8.6SECUT in 2017.
Ambient Sediment Bacteria
The Ambient Sediment Bacteria Study was conducted quarterly from July 2009 to April 2010 to quantify
the re -suspension of fecal coliform and Escherichia coli (E. coli) levels in stream sediment. Specifically,
this study surveyed bacteria concentrations in stream sediment to determine the extent of bacteria in
benthic sediment and if benthic sediment might affect bacteria levels found in surface waters. Thirteen
sites were monitored for the study, three of which were in the Ellerbe Creek Watershed (EL7.9EC,
EL8.1GC, and EL8.5SEC). An initial goal of the project was to determine if a relationship existed between
sediment and surface water levels of fecal coliform bacteria. This initial goal was expanded to include E.
coli and Enterococcus spp. to account for potential future changes to the NC Water Quality Standards for
microbiological indicators.
Beaver Dam Study
The Ellerbe Creek Beaver Dam Study was initiated to determine if installing a beaver dam pond leveler
could be used to increase dissolved oxygen (DO) concentrations downstream of an active beaver dam.
For this project, a pond leveler was installed in a selected beaver dam in the Ellerbe Creek Watershed in
early 2018. DO was continuously monitored by a deployed data -logger at the one-time special study site
DS-1. DO readings were collected both while the pond leveler was in place and active and also when the
leveler was sealed and inactive to determine what effects the pond leveler had on DO concentrations.
Data for this project was collected throughout 2018.
Benthic Spilt Sampling
This study was designed to provide information on the feasibility and accuracy of using the Qualitative
4 (Qual 4) benthic macroinvertebrate sampling methodology for assessing stream health in Triassic
Basin streams rather than the more time -intensive standard qualitative benthic macroinvertebrate
sampling methodology (Full Scale). In this study WQU staff conducted side -by -side split benthic
macroinvertebrate sampling protocols for both the Full Scale and Qual 4 sampling methods and
analyzed the results to see if there was a stream assessment rating difference. The results of this
study supported the recommendation to use the Qual 4 method at all small to medium-sized Triassic
Basin streams (<20 miz drainage area), instead of the Full Scale method. Benthic macroinvertebrate
samples were collected at five sites in the Ellerbe Creek Watershed, EL1.9EC, EL5.5GC, EL5.6EC,
EL7.9EC, and EL8.2EC.
Falls Lake Tributary Algae Study
This study was developed to obtain data on algal and chlorophyll -a loads entering Falls Lake from
contributing streams. Limited periphyton and chlorophyll -a data for this study were collected at EL1.9EC
monthly from August 2010—June 2011.
Industrial BMP Study
The Industrial BMP Study was initiated to evaluate the effectiveness of Stormwater Best Management
Practices (BMPs), now called Stormwater Control Measures (SCMs), at treating industrial stormwater
runoff. Data for this study consisted of field measurements, grab samples and storm samples that were
collected from the SCM at the Durham Area Transportation Authority (DATA) station. A total of five
storm events were monitored between March 23, 2014, and May 1, 2015.
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Long -Term Stream Flow Study
The Long -Term Stream Flow Study has been conducted continuously since 2013 and is currently still
ongoing at the time this report was written. The purpose of this project is to collect streamflow data
that supports the evaluation and validation of hydrologic modeling projects in the sub -watersheds
where the data loggers are deployed. This study provides 15-minute stream stage intervals or water
level and temperature monitoring at multiple sub -watersheds located in the City of Durham. Sampling
sites and data collection procedures for this project have been altered multiple times throughout the
lifespan of the project, however, currently, there are two instream sampling locations and one
atmospheric location associated with the project. One of the instream sampling locations (EL5.5GC) is
located in the Ellerbe Creek Watershed.
Nutrient Loading Study
The Nutrient Loading Study was conducted semi-monthly from January 2010 to May 2011. The
purpose of the Nutrient Loading Study was to generate nutrient data to be used in conjunction with
nutrient data collected from ambient monitoring and discharge data (calculated from flow monitoring
or applicable USGS gauges). These data were compiled to determine nutrient loads from the
applicable watersheds. Six sites were monitored for this study, with one site (EL1.9EC) in the Ellerbe
Creek Watershed.
Rain Catchers Project
The purpose of the Rain Catchers Project was to generate monitoring data to measure and evaluate the
water quality benefits of residential low -impact -development (LID) retrofits (tress, rain barrels, rain
gardens, etc.) in the South Ellerbe Creek watershed in Durham. This was accomplished by monitoring
storm systems, surface water hydrology, and water quality before and after the installation of LID
practices. Therefore, this project was split into two parts. The pre -installation data were collected from
2011— 2013 and the post -installation data were collected from 2016 — 2017. Comprehensive, monthly
water quality data and one-time periphyton samples were collected at EL8.5SEC, and storm samples and
hydrology data were collected at the two, one-time special studies sites (EL — Englewood and EL- Knox)
as well as EL8.5SEC.
Sediment Toxicity Study
The Sediment Toxicity Study was developed to obtain additional information on stream sediment
quality, particularly Polycyclic Aromatic Hydrocarbons (PAHs) and metals, within the City's streams to
determine if sediment toxicity could be a contributor to stressed aquatic communities. For this study,
two different methods (concentrations of select toxics and rate and severity of deformities of midge
larvae) were used to determine potential toxicity to stream invertebrates in stream sediment deposits.
One-time sediment samples were collected in the Summer of 2019 at 5 sites total, 4 of which (EL1.9EC,
EL5.5GC, EL7.1EC, and EL8.5SEC) were in the Ellerbe Creek Watershed.
Desk Studies Completed by the Water Quality Unit
Benthic Functional Feeding Groups
The functional feeding group analysis was primarily an attempt to determine if streams supported their
expected group of organisms; functional feeding groups were based on morpho-behavioral mechanisms
of food acquisition rather than taxonomy and provide links to basic food resource categories, such as
coarse particulate matter, fine particulate matter, periphyton, and prey. Data utilized for this project
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includes collections from 2003 to 2009. Data from 2004-2007 were collected during the summer
months. During 2009, some sites were sampled during the summer and some were sampled during the
winter/spring to evaluate seasonal sampling strategies. The functional feeding group analysis used data
generated from macroinvertebrate collections from 20 sampling locations, five of which were located in
the Ellerbe Creek Watershed (EL1.9EC, EL5.5GC, EL5.6EC, EL7.9EC, and EL8.2EC).
A Habit Type Analysis (HTA) was also conducted on data collected at the Ellerbe sampling locations. The
habitat type analysis was performed in March 2010 using ambient benthic monitoring data from June
2003 to June 2009. The purpose of the HTA is to help elucidate the flow conditions and types of habit
available to aquatic organisms and is based on the method of locomotion that an organism employs.
Sediment Data Study Report
The sediment data study report was prepared by the WQU to summarize available stream sediment
chemistry data from monitoring locations within Durham County and four surrounding counties
(Chatham, Granville, Orange, and Wake). Streambed sediment samples were collected from 123
monitoring locations by the City of Durham, the United States Geological Survey (USGS), and the Duke
University Bernhardt Lab. These samples were analyzed for general categories of stream sediment
properties including biological, chemical, and physical parameters. Summary statistics for the different
sediment properties were also provided in this report and include the general categories of bacteria,
metals, nutrients, polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), pesticides,
other organic compounds, and sediment characteristics, such as density and grain size. Six of the 123
monitoring locations for this project were located in the Ellerbe Creek Watershed.
Water Quality Data Collected by Other City of Durham Units
Watershed Planning Unit (Bank Pin Erosion)
The Watershed Planning Unit worked in conjunction with Kimley Horn and Wildlands Engineering to
install and monitor bank pins at 16 different sites to determine bank erosion rates throughout the City
of Durham. The bank pins were installed in 2014 and during the initial filed visits both near -bank stress
(NBS) and Bank Erosion Hazard Index (BEHI) were categorized as low, moderate, high, very high, or
extreme to track the changes. The bank pin sites were located all over the City with two of the sites
located in Ellerbe Creek (Camden Ave, and Murray Ave). Kimley Horn and Wildlands Engineering
conducted the fieldwork from 2014 — 2018, while the WQU conducted the fieldwork in 2019.
Discharge Monitoring Report (DMR) Data
The North Durham Wastewater Reclamation Facility (NDWRF) collects water quality data on the influent
and effluent to and from their facility at multiple locations within the Ellerbe Creek Watershed
(Upstream 1 and Downstream 2) and upper Falls Lake (D3-1 and D4). The DMR data is collected monthly
and is reported to the North Carolina Division of Water Resources (NC DWR). The data collected for
these reports include both physical and analytical water quality data.
Site Descriptions
In general, the names of City of Durham sample sites that are monitored by the Water Quality group
are characterized by an abbreviation that designates the watershed, general stream mile, and creek
name. For example, EL5.5GC is in the Ellerbe Creek watershed (EL), approximately 5.5 stream miles
upstream of the confluence with Falls Lake, and is located on Goose Creek (GC). The lower the stream
mile, the lower the position the site is in the watershed.
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Occasionally, for special studies mentioned above, there have been limited -time sample sites that do
not follow the standard site name characterization as they are created specifically for a project. These
specific special study sites are not included in the table below but are described in the Special Study
description section. A synopsis of each monitoring site for the Water Quality Unit is included below.
Regular Sampling Sites
EL1.9EC — Glen Road is located on the main stem of Ellerbe Creek just off Glenn Road, upstream of
where the road crosses the creek. This site is the closest monitoring site to where Ellerbe Creek
discharges into upper Falls Lake. This site has been a comprehensive monitoring and nutrient loading
site part of the AMP with samples collected every year from 2004 to the present. This site has also been
a benthic sampling site since 2001 and benthic samples have been collected here for multiple benthic
special studies including the Benthic Functional Feeding Group Study and the Benthic Split Sampling
Study. A midge deformity analysis was conducted and sediment samples were collected at this site as
part of a one-time sampling event in 2019 for the Sediment Toxicity Study to determine if the midge
deformity procedure could accurately determine toxicity levels in creeks. This sample site was also part
of the Nutrient Loading Study where physical and chemical data were collected from 2010 to 2011 and
the Algae Loading Study where Chlorophyll — a samples were collected in 2010 — 2011 as well. Finally,
this is a sample site has been included in the Ambient Split Study which occurs every couple of years
where nutrient samples are collected at multiple sites and delivered to different labs to compare the
results.
ELS.OEC — Club Boulevard is located on the main stem of Ellerbe Creek at the creek crossing on Club Blvd
just west of the North Durham Water Reclamation Facility (NDWRF). This sample site was a
comprehensive sample site that was part of the AMP only in 2004.
EL5.5GC — Camden Avenue is located on Goose Creek approximately 85 feet downstream from the
Camden Ave crossing. This site has been a sampling location part of the AMP since 2004. EL5.5GC
started as a fecal only site from 2004 - 2009 but was changed to a comprehensive site in 2010. As part of
the AMP, samples are collected at this site during the odd years. This sampling site is also a benthic
macroinvertebrate sampling site where benthic samples have been collected from 2001 to the present.
Benthic samples were also collected at this site for the Functional Feeding Group Study in 2010 and the
Benthic Split Study from 2008 — 2010. A midge deformity analysis was conducted and sediment samples
at this site as part of a one-time sampling event in 2019 for the Sediment Toxicity Study to determine if
the midge deformity procedure could accurately determine toxicity levels in creeks. This sampling
location is also part of the Long Term Stream Flow Study where an instream data logger has been
collecting continuous streamflow data since 2013. Finally, this sampling location was part of the
Ambient Split Study which occurs every couple of years where nutrient samples are collected at multiple
sites and delivered to different labs to compare the results.
EL5.6EC — Midland Terrace is located on the main stem of Ellerbe Creek just downstream of the Midland
Terrace culvert. This sampling site has been a comprehensive AMP sampling site since 2004 and it is
currently sampled on the odd years. This sampling location has also been a benthic macroinvertebrate
sampling site since 2001 and has been included in benthic specials studies such as the Benthic
Functional Feeding Group Study in 2010 and the Benthic Split Study from 2008 — 2010. Finally, this
sampling location was also included in the Ambient Split Study which occurs every couple of years where
nutrient samples are collected at multiple sites and delivered to different labs to compare the results.
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EL7.1EC — Club Boulevard and Acadia Street is located on the main stem of Ellerbe Creek inside
Northgate Park just upstream of the Club Boulevard culvert on Acadia Street. This a recently added
comprehensive sampling site for the AMP; samples have only been collected here since 2017. This is
also a nutrient loading site that was switched from EL7.9EC to be closer to the USGS stream gage which
is located just downstream of the Club Boulevard culvert.
EL7.ISEC — Glendale Avenue is located on South Ellerbe Creek, a tributary of the main stem of Ellerbe
Creek. This active sampling site has been a comprehensive site as part of the AMP since 2005.
Additionally, sediment and midge samples were collected here as part of a one-time collection for the
Sediment Toxicity Study in 2019. Finally, this sampling location was also included in the Ambient Split
Study which occurs every couple of years where nutrient samples are collected at multiple sites and
delivered to different labs to compare the results.
EL7.6SECT — Knox Street is located on the South Ellerbe Creek Tributary just off Knox Street between
Ruffin Street and Washington Street on the South Ellerbe Creek Walking Trail. This sampling site was a
fecal only site from 2004 — 2013. This site was dropped in 2015.
EL7.9EC — Murray Avenue is located on the main stem of Ellerbe Creek and can be accessed via the
Ellerbe Creek Trail where the trail crosses Murray Avenue. This was a comprehensive site that was part
of the AMP from 2004 — 2017. This sampling location used to be a nutrient loading site through 2017,
after which the nutrient loading site was switched to EL7.1EC to be closer to the USGS gage to allow for
more accurate calculations. This sampling location has also been a benthic sampling location starting in
2004 and was included in the Functional Feeding Group Study and the Benthic Split Study. Benthic
sample collections were also moved to EL7.1EC after 2017. EL7.9EC was also a sample site for the
Ambient Sediment Bacteria Study, where physical and chemical sediment data were collected from 2009
— 2010 quarterly. Finally, EL7.9EC was also included in the Ambient Split Study that occurs every couple
of years where nutrient samples are collected at multiple sites and delivered to different labs to
compare the results.
EL8.1GC — Holloway Street is located on Goose Creek, a tributary of Ellerbe Creek, upstream from where
the creek crosses Holloway Street near Long Meadow Park. This sampling location has had
comprehensive water chemistry samples collected here since 2004 as part of the AMP. Also, physical
and chemical sediment data were collected at this site quarterly from July 2009 — April 2010 as part of
the Ambient Sediment Bacteria project. Finally, EL8.1GC was also included in the Ambient Split Study
that occurs every couple of years where nutrient samples are collected at multiple sites and delivered to
different labs to compare the results.
EL8.2EC — Stadium Drive is located on the main stem of Ellerbe Creek off of Stadium Drive, just west of
Duke Street. This sample site was a fecal only site part of the AMP from 2004 — 2012. Additionally,
EL8.2EC was a benthic macroinvertebrate sampling site from 2003 — 2012 and was also included in the
Benthic Split Study from 2008 — 2010.
EL8.5SEC — Onslow Street and Club Boulevard is located on South Ellerbe Creek, a tributary of Ellerbe
Creek. The sampling site was originally located on the upstream side of the Club Boulevard culvert,
however, due to a large dead tree that fell, this location became unsafe to access and the sampling
location was moved to the downstream side of the culvert in 2019. EL8.5SEC started as a fecal only site
in 2004 but was changed to a comprehensive site in 2013. Also, physical and chemical sediment data
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were collected at this site quarterly from July 2009 — April 2010 as part of the Ambient Sediment
Bacteria project. Sediment data along with midge deformity analysis was conducted at this site as part
of the Sediment Toxicity Study in 2019. Finally, EL8.5SEC was also a site sampled for the Rain Catchers
Study that was conducted in 2011, 2013, 2016, and 2017. The Rain Catchers Study consisted of extensive
monthly water quality parameters as well as multiple storm sampling events.
EL8.6SECUT— Foster Street and Hunt Street is located on an unnamed tributary of the South Ellerbe
Creek Tributary. This sampling location is near the corner of Foster Street and Hunt Street inside
Durham Central Park just upstream from the pedestrian bridge. EL8.6SECUT started as a fecal only site in
2008 for the AMP and was later changed to a comprehensive site in 2011. This sampling location is very
high up in the watershed and drains most of the central downtown Durham area.
EL10.7EC — Bellevue Avenue is the most upstream sampling site in the watershed and is on the main
stem of Ellerbe Creek just off Bellevue Avenue on the upstream side, inside the Hillandale Golf Course.
This sampling location started as a fecal only site for the AMP in 2004 and was changed to a
comprehensive site in 2009. This site was dropped from the AMP in 2017. EL10.7EC was also included in
the Ambient Split Study that occurs every couple of years where nutrient samples are collected at
multiple sites and delivered to different labs to compare the results.
One-Time/Special Study Sites
EL- Englewood is located directly below two stormwater outfalls that can be accessed by the City of
Durham Right -of -Way that runs between 1708 and 1706 Englewood Avenue. This sampling location was
part of the Rain Catchers Project that was conducted in 2011, 2013, 2016, and 2017. EL -Englewood was
a storm sampling site where an automated sampler was set up and collected extensive water quality
parameters for multiple storms at this location.
EL - Knox is located directly below a stormwater outfall that can be accessed by the City of Durham
Right -of -Way that runs between 1000 Buchanan Boulevard and 1301 Watts Street. This sampling
location was part of the Rain Catchers Project that was conducted in 2011, 2013, 2016, and 2017. EL -
Englewood was a storm sampling site where an automated sampler was set up and collected extensive
water quality parameters for multiple storms at this location.
DS-1— Midland Terrace is located on an unnamed tributary of Ellerbe Creek on the upstream side of
Midland Terrace. This sampling location is directly below a large beaver pond and also very close to the
Ambient sampling site EL5.6EC. This sampling site was part of the Ellerbe Creek Beaver Dam Project
where dissolved oxygen data were collected by a deployed logger in 2017.
407 Morris Street, 423 Morris Street, 404 Hunt Street are the address for the 3 sampling locations that
were part of the AC Coil Study that was conducted in 2015. Samples for this project were not instream
samples, but instead samples that were collected from contained wastewater that was the result of the
HVAC unit cleaning. Both in situ and lab analyzed parameters were analyzed for this project.
DATA Station a series of storm samples were collected at the Stormwater Control Measure (SCM)
located on the Durham Area Transit Authority (DATA) facility as part of the industrial BMP Study. Both
water quality parameters and hydrologic data were collected for this study that was conducted in 2012.
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Monitoring Conducted by the North Carolina Department of
Water Resources (NCDWR)
Ambient Monitoring Systems
The Ambient Monitoring Systems (AMS) Program conducted by NCDWR consists of a network of stations
established to provide site -specific, long-term water quality information on significant rivers, streams,
and estuaries throughout the state. Chemical, physical, and bacterial data are collected at each sampling
location. The program has been active for over forty years. Stations are visited at least quarterly for the
collection of a variety of physical, chemical, and bacterial samples and measurements. Currently, there
are 329 active AMS stations, one of which (J133000) is located in the Ellerbe Creek Watershed. Station
J133000 is located at the intersection of Ellerbe Creek with Glenn Rd. Specific information regarding
methodology and QA/QC details can be found in the Ambient Monitoring Systems (AMS) Program QAPP
(NCDWR, 2017). Data from the AMS project are used to support DWR water quality management
programs, identify long-term temporal patterns, and identify locations where exceedances of State
Water Quality Standards have occurred. These data can be accessed through the National Water Quality
Monitoring Council's Water Quality Portal found at: https://www.watergualitVdata.us//.
Monitoring Conducted by the United States Geological Survey
(USGS)
The USGS conducts streamflow and precipitation monitoring at three sites in the Ellerbe Creek
watershed. Streamflow monitoring data (Discharge and Gage Height) are collected at Ellerbe Creek at
Club Blvd (just downstream of EL7.1EC) and Ellerbe Creek near Gorman NC (EL1.9EC). Precipitation
monitoring data are collected at Ellerbe Creek at Murray Avenue (EL7.9EC). The City of Durham uses
streamflow and precipitation data from these sites for the calculation of pollutant loads and to provide
data for model inputs. The City of Durham funds these gages with a partial match from the USGS.
Streamflow Monitoring
Streamflow monitoring has been conducted at Ellerbe Creek at Club Blvd 2008 (USGS 0208675010) since
July. The monitoring station is currently active and is located on Ellerbe Creek on the downstream side
of the Club Blvd bridge.
Streamflow monitoring has been conducted at Ellerbe Creek near Gorman NC (USGS 02086849) since
October 1982. For a limited time, from 1984 —1985, this station collected additional water quality
parameters including water temperature and specific conductance. Currently this station collects
discharge and gage height measurements since 1982 and 2206 respectively. This monitoring station is
located on Ellerbe Creek on the upstream side of the Glenn Rd bridge near the WQU sampling location
EL1.9EC. Stage height (feet) and discharge (ft3/second) are collected every 15 minutes.
Data for the station at Club Blvd can be acceded at:
httas://waterdata.usgs.gov/nc/nwis/inventorv/?site no=0208675010&agencv cd=USGS
Data for the station located at Glenn Rd can be accessed at:
https://waterdata.usgs.gov/nc/nwis/inventory/?site no=02086849&agency cd=USGS
Page 11 of 16

Precipitation Monitoring
Precipitation monitoring has been conducted at Ellerbe Creek at Murray Ave since August 2008 (USGS
360143078540945). The monitoring station is currently active and located on Ellerbe Creek on the
upstream side of the West Murray Ave bridge. Precipitation data (inches) is recorded every 15 minutes.
Data can be accessed at:
https://waterdata.usgs.gov/nc/nwis/inventory/?site no=360143078540945&agency cd=USGS
Special Study on Ground Water and Surface Water in Ellerbe Creek
This special study looked at groundwater and surface water interactions to determine if groundwater
was a source of elevated nitrate input to Ellerbe Creek. This study focused on Ellerbe Creek because
Ellerbe is one of the main tributaries that drain into upper Falls Lake, a reservoir that is listed for
elevated nutrient levels. The study area was the stretch of Ellerbe Creek that included that NDWRF and
extended to just upstream from where Ellerbe Creek discharges into Falls Lake. Data collected for this
study included streamflow data collection, groundwater -level monitoring, weather and climate data,
hydrograph separation, water -quality sampling, and water -temperature surveys. The results of this
study indicated that groundwater was not a large component of streamflow within Ellerbe Creek nor a
major source of nitrate within the study reach. Full details on the study can be accessed at:
https://Pubs.usgs.gov/sir/2019/5097/sir2Ol95097.pdf.
Stable Isotopes Use of stable isotopes of nitrogen and water to identify sources of
nitrogen in three urban creeks of Durham, North Carolina
The study was a preliminary assessment of nitrate sources in three creeks that feed nutrient impaired
Falls and Jordan Lakes in the vicinity of Durham County, North Carolina, from July 2011 to June 2012.
The three creeks analyzed in this study were Cabin Branch, Ellerbe Creek, and Third Fork Creek. Samples
were collected monthly to determine if sources of nitrate in surface water could be identified on the
basis of their stable isotopic compositions.
The dominant source of nitrate to Cabin Branch, Ellerbe Creek, and Third Fork Creek was the nitrification
of soil nitrogen. Two stormflow samples in Ellerbe Creek and Third Fork Creek had nitrate sources that
were a mixture of the nitrification of soil nitrogen and an atmospheric source that had bypassed some
soil contact through impermeable surfaces within the drainage basin.. Results from this study suggest
that it is possible to distinguish sources of nitrogen and biogeochemical processes on nitrate using stable
isotopes of nitrogen and oxygen in small creeks of Durham County, North Carolina."
Full details of the study can be accessed at:
https://Pubs.er.usgs.gov/publication/sir20145171
Page 12 of 16

Appendix A. Summary Table for Data Collected in Ellerbe Creek
Table begins on the following page.
Page 13 of 16

Status
EL1.9EC
ACTIVE
ELS.OEC
INACTIVE
EL5.5GC
ACTIVE
EL5.6EC
ACTIVE
EL7.1EC
ACTIVE
Project Association(s)
AM, BE, NL, S, FF, AL, BSS, SS
AM
AM, BE, SF, S, FF, BSS, SS
AM, BE, BFF, BSS, SS
AM, BE
AM = Ambient, BE = Benthic, NL = Nutrient Loading, ASB = Ambient Sediment Bacteria, SF = Long Term Stream Flow, RC = Rain Catchers, S = Sediment, FF =
Benthic Functional Feeding, AL = Algae Loading ,BSS = Benthic Split Study, SS = Ambient Split Study
Physical
Conductivity
2004 - present
2005
2010 - present (even years)
2004 - 2010, 2011 - present (odd years)
2017 - present
Flow
-
-
2013 - present
Physical Sediment Data
2019
2019
-
-
Stage Readings
-
-
2015 - present
-
Total Suspended Solids
2004 - present
2004
2010 - present (even years)
2005 - 2010, 2011- present (odd years)
2017 - present
Turbidity
2004 - present
2004
2004 - 2010, 2011- present (OY)
2004 - 2010, 2011- present (odd years)
2017 - present
Water Temperature
2004 - present
2004
2004 - 2010, 2011- present (OY)
2004 - 2010, 2011- present (odd years)
2017 - present
Chemical
Alkalinity
2006 - 2008
-
-
2006 - 2008
-
Aluminum, Total and Dissolved
-
-
-
-
-
Ammonia
2004 - present
2004
2010, 2011- present (odd years)
2005 - 2010, 2011- present (odd years)
2017 - present
Biochemical Oxygen Demand
2004 - present
2004
2010, 2011- present (odd years)
2005 - 2010, 2011- present (odd years)
2017 - present
Cadmium, Total
2006 - 2011
-
2010-2011
2006 - 2011
-
Calcium, Total
2005 - present
2010, 2011- present (odd years)
2005 - 2010, 2011- present (odd years)
2017 - present
Chemical Sediment Data
2019
2019
-
-
Chloride
-
-
-
-
Copper, Total and Dissolved
2004 - present
2004
2010, 2011- present (odd years)
2005 - 2010, 2011 - present (odd years)
2017 - present
Dissolved Oxygen
2004 - present
2004
2004 - 2010, 2011- present (OY)
2004 - 2010, 2011- present (odd years)
2017 - present
Fluoride
-
-
-
Hardness
2004 - present
2004
2010, 2011- present (odd years)
2005 - 2010, 2011- present (odd years)
2017 - present
Iron, Total and Dissolved
-
-
-
Manganese, Total and Dissolved
-
-
Magnesium, Total
2005 - present
-
2010, 2011 - present (odd years)
2005 - 2010, 2011 - present (odd years)
2017 - present
Nitrate + Nitrite
2004 - present
2004
2010, 2011 - present (odd years)
2005 - 2010, 2011 - present (odd years)
2017 - present
Organic Carbon
2013 - 2019
-
-
2017-2019
Orthophosphorus
-
-
-
2004-2006
-
pH
2O04 - present
2004
2004 - 2010, 2011- present (OY)
2004 - 2010, 2011- present (odd years)
2017 - present
Phosphorus, Total
2004 - present
2004
2010, 2011- present (odd years)
2005 - 2010, 2011- present (odd years)
2017 - present
Potassium
-
-
-
-
Sodium
-
-
-
Sulfate
-
Total Kjeldahl Nitrogen
2004 - present
2004
2010, 2011- present (odd years)
2005 - 2010, 2011 - present (odd years)
2017 - present
Zinc, Dissolved
2004 - present
2004
2010, 2011- present (odd years)
2005 - 2010, 2011- present (odd years)
2017 - present
Zinc, Total
2018 - present
-
2019
2019
2018 - present
Biological
Chlorophyll - a
2010-2011
-
-
E. coli
-
-
-
Enterococcus spp.
-
-
-
-
Fecal Coliform
2004 - present
2004
2004 - 2010, 2011- present (OY)
2004 - 2010, 2011- present (odd years)
2017 - present
Macroinvertebrates
2001- present
-
2001- present
2001 - 2009, 2011 - present (odd years)
2019 - present (odd years)
Page 14 of 16

Status
EL7.ISEC
ACTIVE
EL7.6SECT
INACTIVE
EL7.9EC
INACTIVE
EL8.1GC
ACTIVE
Project Association(s)
AM, S, SS
AM
AM, BE, ASB, FF, BSS, SS
AM, ASB, SS
AM = Ambient, BE = Benthic, NL = Nutrient Loading, ASB = Ambient Sediment Bacteria, SF = Long Term Stream Flow, RC = Rain Catchers, S = Sediment, FF =
Benthic Functional Feeding, AL = Algae Loading ,BSS = Benthic Split Study, SS = Ambient Split Study
Physical
Conductivity
2005 - 2010, 2013 - present (odd years)
2004 - 2011, 2013
2004 - 2017 (no 2014)
2004 - 2010, 2011 - present (odd years)
Flow
-
-
-
-
Physical Sediment Data
2019
2009-2010
2009-2010
Stage Readings
-
-
-
Total Suspended Solids
2005 - 2010, 2013 - present (odd years)
-
2004 - 2017 (no 2014)
2004 - 2010, 2011- present (odd years)
Turbidity
2005 - 2010, 2013 - present (odd years)
2004 - 2011, 2013
2004 - 2017 (no 2014)
2004 - 2010, 2011- present (odd years)
Water Temperature
2005 - 2010, 2013 - present (odd years)
2004 - 2011, 2013
2004 - 2017 (no 2014)
2004 - 2010, 2011- present (odd years)
Chemical
Alkalinity
2006 - 2008
-
2006 - 2008
2006 - 2008
Aluminum, Total and Dissolved
-
-
-
-
Ammonia, Total
2005 - 2010, 2013 - present (odd years)
-
2004 - 2017 (no 2014)
2004 - 2010, 2011- present (odd years)
Biochemical Oxygen Demand
2005 - 2010, 2013 - present (odd years)
-
2004 - 2017 (no 2014)
2004 - 2010, 2011- present (odd years)
Cadmium, Total
2006 - 2010
-
2006 - 2011
2006 - 2011
Calcium, Total
2005 - 2010, 2013 - present (odd years)
-
2005 - 2017 (no 2014)
2005 - 2010, 2011- present (odd years)
Chemical Sediment Data
2019
-
2009-2010
2009-2010
Chloride
-
-
-
-
Copper, Total and Dissolved
2005 - 2010, 2013 - present (odd years)
-
2004 - 2017 (no 2014)
2004 - 2010, 2011- present (odd years)
Dissolved Oxygen
2005 - 2010, 2013 - present (odd years)
2004 - 2011, 2013
2004 - 2017 (no 2014)
2004 - 2010, 2011- present (odd years)
Fluoride
-
-
-
-
Hardness
2005 - 2010, 2013 - present (odd years)
-
2004 - 2017 (no 2014)
2004 - 2010, 2011- present (odd years)
Iron, Total and Dissolved
-
-
-
-
Manganese, Total and Dissolved
-
-
-
-
Magnesium, Total
2005 - 2010, 2013 - present (odd years)
-
2004 - 2017 (no 2014)
2005 - 2010, 2011 - present (odd years)
Nitrate/Nitrite
2005 - 2010, 2013 - present (odd years)
-
2004 - 2017 (no 2014)
2004 - 2010, 2011 - present (odd years)
Organic Carbon
-
-
2013-2017
2009-2010
Orthophosphorus
2005 - 2006
-
2004 - 2006
2004 - 2006
pH
2O05 - 2010, 2013 - present (odd years)
2004 - 2011, 2013
2004 - 2017 (no 2014)
2004 - 2010, 2011- present (odd years)
Phosphorus, Total
2005 - 2010, 2013 - present (odd years)
-
2004 - 2017 (no 2014)
2004 - 2010, 2011- present (odd years)
Potassium
-
-
-
-
Sodium
-
-
-
-
Sulfate
-
-
Total Kjeldahl Nitrogen
2005 - 2010, 2013 - present (odd years)
-
2004 - 2017 (no 2014)
2004 - 2010, 2011- present (odd years)
Zinc, Dissolved
2005 - 2010, 2013 - present (odd years)
-
2004 - 2017 (no 2014)
2004 - 2010, 2011- present (odd years)
Zinc, Total
2019 - present (odd years)
-
-
2019 - present (odd years)
Biological
Chlorophyll - a
-
-
-
E. coli
-
2009-2010
2009 -2010
Enterococcus spp.
-
-
2009-2010
2009-2010
Fecal Coliform
2005 - 2010, 2013 - present (odd years)
2004 - 2011, 2013
2004 - 2017 (no 2014)
2004 - 2010, 2011- present (odd years)
Macroinvertebrates
-
-
2001- 2009, 2011 - 2017 (odd years)
-
Page 15 of 16

Status
EL8.2EC
INACTIVE
EL8.5SEC
ACTIVE
EL8.6SECUT
ACTIVE
EL10.7EC
INACTIVE
Project Association(s)
AM, BE, BSS
AM, ASB, RC, S
AM, SS
AM, SS
AM = Ambient, BE = Benthic, NIL = Nutrient Loading, ASB = Ambient Sediment Bacteria, SF = Long Term Stream Flow, RC = Rain Catchers, S = Sediment, FF = Benthic
Functional Feeding, AL = Algae Loading ,BSS = Benthic Split Study, SS = Ambient Split Study
Physical MMM
Conductivity
2004 - 2012 (no 2008)
2004 - 2013, 2015 - 2017, 2019 - present (odd years)
2008 - 2013, 2015 - present (odd years)
2004 - 2013, 2015, 2017
Flow
-
-
-
-
Physical Sediment Data
-
2009 - 2010, 2019
-
-
Stage Readings
-
-
-
-
Total Suspended Solids
2004
2011- 2013, 2015 - 2017, 2019 - present (odd years)
2011- 2013, 2015 - present (odd years)
2009 - 2013, 2015, 2017
Turbidity
2004 - 2012 (no 2008)
2004 - 2013, 2015 - 2017, 2019 - present (odd years)
2008 - 2013, 2015 - present (odd years)
2004 - 2013, 2015, 2017
Water Temperature
2004 - 2012 (no 2008)
2004 - 2013, 2015 - 2017, 2019 - present (odd years)
2008 - 2013, 2015 - present (odd years)
2004 - 2013, 2015, 2017
Chemical
Alkalinity
-
2012 - 2013, 2016 - 2017
-
-
Aluminum, Total and Dissolved
-
2011- 2013, 2016 - 2017
-
-
Ammonia, Total
2004
2011- 2013, 2015 - 2017, 2019 - present (odd years)
2011- 2013, 2015 - present (odd years)
2009 - 2013, 2015, 2017
Biochemical Oxygen Demand
2004
2011- 2013, 2015 - 2017, 2019 - present (odd years)
2011- 2013, 2015 - present (odd years)
2009 - 2013, 2015, 2017
Cadmium, Total
-
2007, 2011, 2016
2009-2011
2009-2011
Calcium, Total
-
2011- 2013, 2015 - 2017, 2019 - present (odd years)
2009 - 2013, 2015 - present (odd years)
2009 - 2013, 2015, 2017
Chemical Sediment Data
-
2009 - 2010, 2019
-
-
Chloride
-
2011- 2013, 2016 - 2017
-
-
Copper, Total and Dissolved
2004
2011- 2013, 2015 - 2017, 2019 - present (odd years)
2009 - 2013, 2015 - present (odd years)
2009 - 2013, 2015, 2017
Dissolved Oxygen
2004 - 2012 (no 2008)
2004 - 2013, 2015 - 2017, 2019 - present (odd years)
2008 - 2013, 2015 - present (odd years)
20094 - 2013, 2015, 2017
Fluoride
-
2011- 2013, 2015 - 2016)
-
-
Hardness
2004
2011- 2013, 2015 - 2017, 2019 - present (odd years)
2011- 2013, 2015 - present (odd years)
2009 - 2013, 2015, 2017
Iron, Total and Dissolved
-
2011- 2013, 2016 - 2017
-
-
Manganese, Total and Dissolved
-
2011- 2013, 2016 - 2017
-
-
Magnesium, Total
-
2011- 2013, 2015 - 2017, 2019 - present (odd years)
2008 - 2013, 2015 - present (odd years)
2009 - 2013, 2015, 2017
Nitrate/Nitrite
2004
2011- 2013, 2015 - 2017, 2019 - present (odd years)
2011- 2013, 2015 - present (odd years)
2009 - 2013, 2015, 2017
Organic Carbon
-
2011- 2013, 2016 - 2017
-
-
Orthophosphorus
2004
-
-
-
pH
2O04 - 2012 (no 2008)
2004 - 2013, 2015 - 2017, 2019 - present (odd years)
2008 - 2013, 2015 - present (odd years)
2004 - 2013, 2015, 2017
Phosphorus, Total
2004
2011- 2013, 2015 - 2017, 2019 - present (odd years)
2011- 2013, 2015 - present (odd years)
2009 - 2013, 2015, 2017
Potassium
-
2011- 2013, 2016 - 2017
-
-
Sodium
-
2011- 2013, 2016 - 2017
-
-
Sulfate
-
2011- 2013, 2016 - 2017
-
Total Kjeldahl Nitrogen
2004
2011 - 2013, 2015 - 2017, 2019 - present (odd years)
2011 - 2013, 2015 - present (odd years)
2009 - 2013, 2015, 2017
Zinc, Dissolved
2004
2011 - 2013, 2015 - 2017, 2019 - present (odd years)
2009 - 2013, 2015 - present (odd years)
2009 - 2013, 2015, 2017
Zinc, Total
-
2011 - 2013, 2015 - 2017, 2019 - present (odd years)
2017 - present (odd years)
-
Biological
Chlorophyll - a
-
-
-
E. coli
-
2009-2010
-
-
Enterococcus spp.
-
2009-2010
-
-
Fecal Coliform
2004 - 2012 (no 2008)
2004 - 2013, 2015 - 2017, 2019 - present (odd years)
2008 - 2013, 2015 - present (odd years)
2004 - 2013, 2015, 2017
Macroinvertebrates
2003 - 2007, 2009 - 2012
-
-
-
Page 16 of 16