I-57_Long Term Stream Flow Project Annual Report 2019 Final Draft

Date:
To:
CITY OF
DURHAM
June 1811, 2020
Memo
Michelle Woolfolk, Sr. Environmental Planning and Compliance Manager
Through: Joey Smith, Environmental Planning and Compliance Analyst
From: Blaine Lary, Environmental Planning and Compliance Specialist
Subject: Long Term Stream Flow Monitoring (Project 09-010) - CY2019 Summary
Report
101 City Hall Plaza, Durham, NC 27701 919.560.1200 DurhamNC.gov 1
Follow Us @Ciittyo© rhamNNCC

Table of Contents
Tableof Contents................................................................................................................................................................... 2
Figures.................................................................................................................................................................................... 2
Tables...................................................................................................................................................................................... 3
Introduction................................................................................................................................................................................ 4
Precipitation................................................................................................................................................. 5
ProjectMethods...................................................................................................................................................................... 5
QA/QC Results........................................................................................................................................................................ 5
Loggerdata.................................................................................................................................................. 5
FieldData..................................................................................................................................................10
CrossSection Profiles.........................................................................................................................11
DischargeMeasurements.................................................................................................................15
Conclusions.............................................................................................................................................................................15
SiteLocation issues.............................................................................................................................15
DischargeMonitoring...........................................................................................................................15
CrossSection Documentation........................................................................................................... 16
References..............................................................................................................................................................................17
Appendix I - Recorded readings at CC2.5CC and EL5.5GC from January 1 st- December 31 st,
2019. Periods are defined by time between collection of field measurements.....................................18
Figures
Figure 1: Study sites EL5.5GC (Camden Ave.), CC2.5CC (Scott King Rd.), and Public Works
OperationsCenter(PWOC)..........................................................................................................4
Figure 2: Level logger data for CC2.5CC from January 2019 through June 2019. The dashed
line from January 181h to February 28th, 2019 marks a period where logger values were 0, likely
due to an equipment error. In April, values began falling below 0, possibly indicating that the
logger was out of water. This trend extended through the remainder of 2019 .............................7
Figure 3: Logger depth data at CC2.5CC for the month of May 2019. Data tended to follow a
diurnal oscillating pattern, likely attributed to evapotranspiration variations between daytime and
nighttime....................................................................................................................................... 8
Figure 4: Logger depth against precipitation at site EL5.5GC. Logger depth increases during
precipitation events as expected...................................................................................................9
Figure 5: Blank field sheet displaying measurements taken at logger wells during data
downloads...................................................................................................................................10
Figure 6: Cross sections of site CC2.5CC in 2018 and 2019. The profile of 2019 suggests that
the channel eroded between surveys. The orange dashed line indicates the water level
measured during 2019 discharge measurements.......................................................................13
Figure 7: Cross sections of site EL5.5GC in 2018 and 2019. Differences in the channel shape
indicate channel aggregation, but this may be due to staff error. The left bank facing upstream
101 City Hall Plaza, Durham, NC 27701 919.560.1200 DurhamNC.gov 1
Follow Us @Ciittyo© rhamNC

gained approximately 2.5 feet of elevation between surveys, which is unlikely. The orange
dashed line indicates the water level measured during 2019 discharge measurements ............ 14
Tables
Table 1: Data timeline for CC2.5CC and EL5.5GC. Boxes marked with `X' indicate that the
majority of data collected for that month were deemed useable in the QA process.....................5
Table 2: 2019 field measurements for site CC2.5CC. Instances where "Membrane to Surface"
values were negative are highlighted in red. In January and February, the logger was damaged
byhigh flow.................................................................................................................................11
Table 3: 2019 field measurements for site EL5.5GC. Instances where "Membrane to Surface"
values were negative are highlighted in red................................................................................11
101 City Hall Plaza, Durham, NC 27701 919.560.1200 DurhamNC.gov 1
Follow Us @Ciittyo© rhamNC

Introduction
As part of ongoing monitoring efforts of streamflow within the City of Durham, the Monitoring
and Assessment Unit has deployed pressure transducers to continuously monitor stream stage
in the Crooked Creek and Goose Creek watersheds (Figure 1). These transducers record stage
every 15 minutes and support the evaluation and validation of hydrologic modeling projects in
the sub -watersheds where the data loggers are deployed. City staff collect data monthly and
perform yearly discharge measurements and cross section surveys at each site. Per the Long
Term Stream Flow Project Quality Assurance Project Plan (QAPP), a report is to be completed
for each year of data collection. This report analyzes data for January 1st to December
311t,2019. During that period, technical issues resulted in large periods of the data being
rendered unusable. Staff also identified inconsistencies in field collection methods.
mmdu r L=k
Camden Ave.
Jc
'end A LiWr lick C'_c
1414
TI' nr �.rck 1 , �ic�reck
J
reek Pwoc
1 `-''
iJ riTCmrk (WCI
51 I� SycamoieC ek{WC)
}
0 k/
-- - H060 logger Waler level Site
�('\t Q AV ..ph.- R.I rent. Logger
Scott King Rd. M.wr sc.n na
- VJaler Sheds
IMvn Smucc: City of 1 "I"
I ns Long Term
Mug PrcPnred by 5namwntrr nud (ilsrrvi Stream Flow
Puhlic Wnrks nn August 2, 2018_ In}orma i
d.pi�lzdh�renninf..errren��pnrpnaesn.I, .dia Monitoring Sites
CITY OF umpiled Gmn the best ae'ni3abla sources. The City of 2
.1M,h
DURHAM v onihn,nm C.-ty assumes na rcsw—bilily
t'or errors arising tm,n use ar misue urth,, map. O Miles
Figure 1: Study sites EL5.5GC (Camden Ave.), CC2.5CC (Scott King Rd.), and Public Works Operations Center
(PWOC).
101 City Hall Plaza, Durham, NC 27701 919.560.1200 DurhamNC.gov 1
Follow Us @Ciittyo© rhamNC

Precipitation
Precipitation data were downloaded for 2019 in its entirety from USGS station 0209725960
(Third Fork Creek at MILK Parkway). Precipitation amounts were recorded to the nearest 0.01
inch at 5-minute intervals. For this summary, storm events were defined as periods in which at
least 0.2' of rainfall had occurred within the last 12 hours. Based on this definition, there were a
total of 58 precipitation events during 2019 with the year's total accumulating to 42.24 inches.
Durham County also experienced drought conditions during September and October of 2019.
Conditions in Durham County were classified by the North Carolina Drought Management
Advisory Council as abnormally dry in the second week of September, and by October classified
as D1, a moderate drought. The D1 classification lasted until mid -October, by which point it
returned to abnormally dry. These conditions lasted through the last week of November.
Project Methods
Two Onset HOBO U20-001-01 pressure transducer level loggers were deployed midstream at
sites CC2.5CC and EL5.5GC. A third was deployed out of water at the Public Works Operations
Center (PWOC) to measure atmospheric pressure. These loggers measure barometric pressure
and temperature and were programmed to collect data points at 15-minute intervals. City staff
conduct data downloads monthly. Pressure data is then corrected to account for the difference
between atmospheric pressure and submerged pressure and corrected for temperature using
proprietary software from Onset. Data validation was completed in March and April of 2020 in
preparation of this memo. Discharge measurements were collected on March 25th, 2019 and
cross section profiles were measured on August 22nd, 2019.
QA/QC Results
Logger data
During the QA process, timeframes with questionable or unreliable logger level data were
flagged. Table 1 displays a timeline of 2019 and notates whether the majority of each month's
data passed the QA check, or if they were flagged as faulty. Overall, site CC2.5CC contained
roughly 1.5 months of useable data and EL5.5GC contained about 9 months of useable data.
Table 1: Data timeline for CC2.5CC and EL5.5GC. Boxes marked with Y indicate that the majority of data collected
for that month were deemed useable in the QA process.
Figure 2 displays logger depth values for CC2.5CC from January 2019 through June 2019.
Data are acceptable from January 1 st — January 18th, 2019, then from January 18th — February
28th logger values all read 0, likely indicating an equipment error. Data from the month of
March was considered reliable. Beginning in April, however, logger values began falling below
0, and with the exception of precipitation spikes, and remained negative for the rest of the year
(See Appendix I, data from October 23rd to December 1611, 2019). While a decrease in
streamflow levels is observed during the transition from late winter to spring, it is suspected that
the probe deployed at CC2.5CC drifted out of calibration based on comparisons made between
101 City Hall Plaza, Durham, NC 27701 919.560.1200 DurhamNC.gov Follow Us @CityofDurhamNC
00 0

all probes in a stable environment following the observation of negative values in data in
February, 2020. Figure 3 displays representative logger level data for the month of May. Depth
data tended to follow a diurnal cycle, likely due to normal evapotranspiration variation between
daytime and nighttime, and also captured storm events on May 4th-May 5th, May 131h, and May
26th. Graphs of available data are included in Appendix I.
Data for EL5.5GC failed QA checks for January, February, and March, and passed QA checks
for the months of April through December 2019. Additionally, the logger at this site was lost at
the end of 2018 and new equipment had to be ordered. The logger was reinstalled on January
18th, 2019 but became dislodged and was reinstalled a second time on February 20th, 2019. On
March 11th, 2019, the logger was installed again and remained functional for the rest of the year.
During this time there were extended periods in which logger recorded negative depth values,
indicating it was not submerged (Appendix 1).
Figure 4 displays logger depth data at EL5.5GC from July 25th to August 22nd, 2019 compared
to precipitation data from USGS station 0209725960. As would be expected, increases in level
logger depth occurred during precipitation events. An exception to this statement occurred on
July 29th, 2019 when an increase in logger depth to approximately 0.5 feet was recorded without
an accompanying precipitation event observed at USGS station 0209725960. It is possible that
a localized rainfall event occurred upstream of EL5.5GC, but not over the station in the Third
Fork Creek watershed.
101 City Hall Plaza, Durham, NC 27701 919.560.1200 DurhamNC.gov 1
Follow Us @Ciittyo© rhamNNCC

CC2.5CC 1/1/19 - 6/ 8/19
4
3
41
D-
oi 2
L
tM
1
0
-1
111/2019 1/21/2019 211012019 3J2f2019 3/27f2019 4111/2019 511/2019 5/2112019 6/10/2019
Figure 2: Level logger data for CC2.5CC from January 2019 through June 2019. The dashed line from January 18t" to February 28t", 2019 marks a period where
logger values were 0, likely due to an equipment error. In April, values began falling below 0, possibly indicating that the logger was out of water. This trend
extended through the remainder of 2019.

CC2.5CC 4 0/19 - 5/31/19
—Log;er depth PrLdpitation
0.8 0-4
0.6
0.4
0.2
0.2
0.15
0
0
❑
-0.2
o
*gyp
0.1 ca
ai
o -0-4
CL
J
IAA
-0.6
0.05
-0.9
-
-1 0
4f30f1 5f5f1 511�}1 5}15f1�J Sf Of1 5/25/19 5)?of19
Figure 3: Logger depth data at CC2.5CC for the month of May 2019. Data tended to follow a diurnal oscillating pattern, likely attributed to evapotranspiration
variations between daytime and nighttime.

4.5
4
3.5
1
0.5
0
7/25/19
EL5.5CC 7/ 5/19 - S f 2 /19
7/50/19 8f4f19
�Log;er depth Precipitation
BJSn 9 9/14/19 9/19/19
Figure 4: Logger depth against precipitation at site EL5.5GC. Logger depth increases during precipitation events as expected.
0.25
0.2
o.15
0
0.1
L
CL
0.05
0

Field Data
During monthly level logger data downloads, staff also recorded field measurements. Figure 5
displays a blank field sheet containing a sketch of these measurements.
ELS.5GC Dawnstream of Camden Avenue bridge
Date:
Time:
Field Qeo-r:
Well Condition:
Logger Condition:
Staff gage (ft):
Flow Sev: 1 2 3 4 5
Rain Last 24hrs?: Y N
Comments:
Top Of Casirlg;TOCI
A: TOC to Bed (ft}
6: TOC to Water ;ft)
C: TUC to Well bottom (I't)
bep& "m:bojmm of:rap rim Lc: mern&aree (ft) .
Figure 5: Blank field sheet displaying measurements taken at logger wells during data downloads.
Tables 2 and 3 display an abridged version of 2019 field measurements containing a calculated
field called "Membrane to Surface". The "Membrane to Surface" value is calculated by
subtracting measurement "B" from "Cap Bottom to Top Membrane" and represents the height of
water above the logger. This value serves as a quality assurance point, as it should equal the
sensor's logged depth at the time of collection. "Membrane to Surface" values are negative for
the majority of the year at both sites, which would imply that the loggers were above water
during these periods. Charts for EL5.5GC indicate that there were many periods where the
logger was not submerged.
101 City Hall Plaza, Durham, INC 27701 919.560.1200 DurhamNC.gov I it Follow Us @Cityo© rhamNC

Table 2: 2019 field measurements for site CC2.5CC. Instances where "Membrane to Surface" values were negative
are highlighted in red. In January and February, the logger was damaged by high flow.
CC2.5CC
Date
A
B
Cap Btm to
Top Mem
Mem to
Surface
Depth
Logger
Reading
1/18/2019
3.91
2.07
2.97
0.90
0*
2/28/2019
3.30
1.48
2.93
1.45
0*
3/25/2019
3.33
2.50
2.94
0.44
0.43
4/30/2019
3.92
3.20
2.96
-0.24
-0.36
5/31 /2019
3.95
3.32
2.96
-0.36
-0.78
6/28/2019
4.19
3.33
2.98
-0.35
-0.29
7/25/2019
3.94
3.16
2.96
-0.20
-0.13
8/22/2019
3.96
3.30
2.96
-0.34
-0.41
9/30/2019
3.92
3.40
2.96
-0.44
-0.40
10/23/2019
3.95
3.04
2.96
-0.08
-0.20
12/16/2019
4.00
2.89
2.98
0.09
-0.19
Table 3: 2019 field measurements for site EL5.5GC. Instances where "Membrane to Surface" values were negative
are highlighted in red.
EL5.5GC
Date
A
B
Cap Btm to
Top Mem
Mem to
Surface
Depth
Logger
Reading
1 /18/2019
5.18
3.38
3.30
-0.08
0.32
2/28/2019
5.33
3.30
3.42
0.12
0.55
3/25/2019
4.94
3.37
3.28
-0.09
0.23
4/30/2019
5.06
3.53
3.29
-0.24
0.10
6/28/2019
5.17
3.75
3.3
-0.45
-0.04
7/25/2019
4.85
3.5
3.3
-0.2
0.06
8/22/2019
5.1
3.64
3.32
-0.32
-0.05
9/30/2019
5.17
3.55
3.32
-0.23
0.05
10/23/2019
4.94
3.44
3.26
0.18
0.11
12/16/2019
5.17
3.38
3.2513
L--O.
0.32
Cross Section Profiles
Cross Section measurements were collected for each site on August 22nd, 2019 in accordance
with the QAPP guidelines. A tape measure was suspended across the channel, perpendicular
to the direction of flow, and each end tied to a piece of rebar. Beginning at stream right (the
bank on the right when facing downstream), a pocket rod or survey rod is used to measure the
vertical distance from the top of the monument to the measuring tape. Vertical distance
measurements were repeated at different points along the transect wherever there was a break
101 City Hall Plaza, Durham, NC 27701 919.560.1200 DurhamNC.gov 1
Follow Us @Ciittyo© rhamNC

in slope, as well as at these key features: top of bank (right and left), bankfull (right and left),
edge of water (right and left), thalweg, and left monument/rebar.
In 2018 and 2019, staff members began the surveys from the left bank facing downstream when
they should have begun on the left bank facing upstream. Therefore, data were corrected for
this report to align with QAPP protocol. Figures 6 and 7 show comparative cross sections of
CC2.5CC and EL5.5GC in 2018 and 2019 with measurements beginning on the left bank facing
upstream.
Changes in the cross section profiles of CC2.5CC indicate that erosional forces had modified
the channel's morphology between 2018 and 2019, while sedimentation deposition occurred at
EL5.5GC. Durham's Triassic Basin streams are generally subject to bank erosion and not
aggregation. But numerous hurricanes, notably Hurricanes Florence and Michael in September
and October of 2018, did occur, which could have resulted in major sedimentation in the
floodplain and stream beds. this may be the case with the left bank of EL5.5GC gaining roughly
2.5 feet of elevation between 2018 and 2019.
101 City Hall Plaza, Durham, NC 27701 919.560.1200 DurhamNC.gov 1
Follow Us @Ciittyo© rhamNC

0.
a
m
G
3
6
9
CC2.5CC Cross Sections 2015 and 2019
Width (ft.)
O Lf` -7 U) r3 Lr rj Ln O
—2Q19 Profile
—2Q18 Profile
Figure 6: Cross sections of site CC2.5CC in 2018 and 2019. The profile of 2019 suggests that the channel eroded between surveys. The orange dashed line
indicates the observed water level measured during 2019 discharge measurements.

EL5.5GC Cross Sections 2018 and 2019
Width (ft.)
C3 in Q L, a U1. CD in C3 in C� tn
O M ri ri rN r*! In In 'T Lf1 lf1 l0 l0
3
12
15
—2019 Profile
—2018 Profile
Figure 7: Cross sections of site EL5.5GC in 2018 and 2019. Differences in the channel shape indicate channel aggregation. The left bank facing upstream gained
approximately 2.5 feet of elevation between surveys. The orange dashed line indicates the observed water level measured during 2019 discharge measurements.

Discharge Measurements
Stream discharge measurements were taken on March 25t", 2019 following the QAPP protocol.
Using a SonTek/YSI FlowTracker ADV meter, staff measured discharge at a minimum of 20
subsections along the established cross sections. Once sampling was complete, the meter
added the discharge of each subsection to calculate total discharge of cubic feet per second
(cfs). Total discharge amounted to 0.77 cfs at CC2.5CC and 2.56 cfs at EL5.5GC.
Conclusions
The City of Durham Long Term Stream Flow QAPP states that "The purpose of the Long Term
Stream Flow Monitoring QAPP is to ensure the field data collected is of sufficient quality to
support the evaluation and validation of hydrologic modeling projects in the sub -watersheds
where the data loggers are deployed". During data review for this report, staff have identified
several areas that may improve data generated with minimal effort. These are further discussed
below.
Site Location issues
The majority of Durham's city limits are located within the Triassic Basin Ecoregion, whose
geology is characterized by conglomerates, sandstones, siltstones, and mudstones, with
diabase intrusions. These materials erode to form sandy and mobile stream beds, which makes
them a dominating factor in the region's hydrogeomorphology. Because the channel substrates
of Durham's streams are highly susceptible to erosional and depositional forces, stream
thalwegs often migrate. This makes it difficult to compare staff gage and depth logger level
readings over time without adequate controlling features to limit these conditions. Additionally,
field measurements (Tables 2&3) as well as corrected data indicate that both level loggers were
not submerged for extended periods of time. It may be prudent to look for alternative sites within
the same reach. More appropriate sites with morphology -controlling features may be located
near culverts or in natural areas with more stable substrates that are less subject to aggregation
and degradation.
Discharge Monitoring
The QAPP requires that discharge measurements are taken once a year at both sites, which
would amount to three points over the course of the 3-year plan. Three points may be too few
to develop an accurate stage -discharge curve or assess the impact of major storm events on
the hydrogeomorphology. Moreover, stage and discharge are primarily functions of
precipitation, not time. Collecting points one year apart may not guarantee a wide range in flow
conditions. To support the evaluation and validation of hydrologic modeling projects in Durham's
sub -watersheds, more robust stage -discharge curves would be helpful. To develop these
curves, it is recommended that additional discharge measurements be taken on a more frequent
basis. Moreover, discharge measurements should target different flow conditions to gather a
wider range of data points.
101 City Hall Plaza, Durham, NC 27701 919.560.1200 DurhamNC.gov 1
Follow Us @Ciittyo© rhamNC

Cross Section Documentation
Given the mobile nature of the stream bed and bank changes documented in cross sections
from 2018 and 2019, better documentation of stream banks would be recommended. To save
time, staff may photograph the cross-section site periodically, to monitor for changes that may
occur between cross section measurements. This study was originally intended to last three
years from the completion of the QAPP in 2018. This would set the project's end date to 2020.
However, the length will likely need to be extended to include the recommended improvements.
101 City Hall Plaza, Durham, NC 27701 919.560.1200 DurhamNC.gov 1
Follow Us @Ciittyo© rhamNC

References
City of Durham, 2018. City of Durham Long Term Stream Flow Monitoring (Project #09-010)
Quality Assurance Project Plan. Available on the COD SW server at F:\SW\Division Files\Water
Quality\Projects\09-010 LongTermStream Flow\Documents\QAPP\
101 City Hall Plaza, Durham, NC 27701 919.560.1200 DurhamNC.gov 1
Follow Us @Ciittyo© rhamNC

Appendix I - Recorded readings at CC2.5CC and EL5.5GC from January 1st -
December 31 st, 2019. Periods are defined by time between collection of field
measurements.
CC2.5CC January 2019
5
4
3 —
L Suspected equipment error
beginning on January 181n
0 1 "O�j
a
o�
o a
-1
-2
-3
1/1/2019 1/6/2019 1/11/2019 1/16/2019 1/21/2019 1/26/2019 1/31/2019
101 City Hall Plaza, Durham, NC 27701 919.560.1200 DurhamNC.gov 1
Follow Us @Ciittyo© rhamNC

5
4
3
2
r
a
0
W
on
tto
0 0
-1
-2
-3
2/1/2019
5
4
3
$ 2
r
a
(U 1
0
a�
M
0 0
-1
-2
3/V2019
CC2.5CC February 2019
Suspected equipment error
extending January 18t" through
February 28tn
2/6/2019 2/11/2019 2/16/2019
CC2.5CC March 2019
2/21/2019 2/26/2019
3/6/2019 3/11/2019 3/16/2019 3/21/2019 3/26/2019 3/31/2019
101 City Hall Plaza, Durham, NC 27701 919.560.1200 DurhamNC.gov Follow Us @CityofDurhamNC
00 10

5 1
4
3
$ 2
r
a
0
as
0 0
-1
-2
-3
4/1/2019
5
4
3
$ 2
r
a
0
a�
0
-1
-2
-3
5/1/2019
CC2.5CC April 2019
4/6/2019 4/11/2019 4/16/2019
CC2.5CC May 2019
4/21/2019 4/26/2019 5/V2019
5/6/2019 5/11/2019 5/16/2019 5/21/2019 5/26/2019 5/31/2019
101 City Hall Plaza, Durham, NC 27701 919.560.1200 DurhamNC.gov follow Us @CityofDurhamNC
00 a

5
4
3
r
a
0 1
au
0 0
1
-2
-3
6/1/2019
5
4
3
r
a
0
a�
0
-1
-2
-3
7/1/2019
CC2.5CC June 2019
6/6/2019 6/11/2019 6/16/2019
CC2.5CC July 2019
6/21/2019 6/26/2019 7/V2019
7/6/2019 7/11/2019 7/16/2019 7/21/2019 7/26/2019 7/31/2019
101 City Hall Plaza, Durham, NC 27701 919.560.1200 DurhamNC.gov follow Us @CityofDurhamNC
00 a

5
4
3
$ 2
r
a
0
as
0 0
-1
-2
-3
8/1/2019
5
4
3
$ 2
r
a
0
a�
0
OV
-1
-2
-3
9/1/2019
CC2.5CC August 2019
8/6/2019 8/11/2019 8/16/2019 8/21/2019
CC2.5CC September2019
8/26/2019 8/31/2019
9/6/2019 9/11/2019 9/16/2019 9/21/2019 9/26/2019 10/1/2019
101 City Hall Plaza, Durham, NC 27701 919.560.1200 DurhamNC.gov follow Us @CityofDurhamNC
00 a

5
4
3
$ 2
r
a
0
as
0
-1
-2
-3
10/1/2019
5
4
3
$ 2
r
a
0
a�
0 0
-1
-2
-3
1 V112019
CC2.5CC October 2019
10/6/2019 10/ 11/2019 10/ 16/2019 10/2 V2019
CC2.5CC November2019
10/26/2019 10/3 V2019
11/6/2019 11/11/2019 11/ 16/2019 11/21/2019 11/26/2019 12/ 1/2019
101 City Hall Plaza, Durham, NC 27701 919.560.1200 DurhamNC.gov follow Us @CityofDurhamNC
00 a

P.
-3
12/1/2019 12/6/2019
CC2.5CC December 2019
12/11/2019 12/16/2019
12/21/2019
12/26/2019 12/31/2019
101 City Hall Plaza, Durham, NC 27701 1 919.560.1200 1 DurhamNC.gov
Follow Us @CityofDurhamNC
0© 10

8
7
6
5
s 4
a
d
O
NO3
NO
0
J
2
1
0
-1
1/18/2019
8
7
6
5
s 4
a
O
NO
3
NO
0
J
2
1
0
1
2/1/2019
EL5.5GC January 2019
1/20/2019 1/22/2019 1/24/2019 1/26/2019 1/28/2019 1/30/2019
EL5.5GC February 2019
2/6/2019 2/11/2019 2/16/2019 2/21/2019 2/26/2019
101 City Hall Plaza, Durham, NC 27701 919.560.1200 DurhamNC.gov follow Us @CityofDurhamNC
00 a

e
7
6
5
s 4
a
d
O
NO
3
NO
0
J
2
1
0
-1
3/1/2019
a
7
6
5
s 4
a
O
NO
3
NO
0
J
2
1
0
-1
4/1/2019
3/6/2019 3/11/2019
EL5.5GC March 2019
3/16/2019
EL5.5GC April 2019
3/21/2019 3/26/2019 3/31/2019
4/6/2019 4/11/2019 4/16/2019 4/21/2019 4/26/2019 5/1/2019
101 City Hall Plaza, Durham, NC 27701 919.560.1200 DurhamNC.gov follow Us @CityofDurhamNC
00 a

e
7
6
5
s 4
a
d
O
NO
3
NO
0
J
2
1
0
-1
5/1/2019
a
7
6
5
s 4
a
O
NO
3
NO
0
J
1
0
-1
6/1/2019
EL5.5GC May 2019
5/6/2019 5/11/2019 5/16/2019 5/21/2019 5/26/2019 5/31/2019
EL5.5GC June 2019
6/6/2019 6/11/2019 6/16/2019 6/21/2019 6/26/2019 7/V2019
101 City Hall Plaza, Durham, NC 27701 919.560.1200 DurhamNC.gov follow Us @CityofDurhamNC
00 10

e
7
6
5
s 4
a
d
O
NO3
NO
0
J
2
1
0
1
7/1/2019
8
7
6
5
s 4
a
d
O
NO3
NO
0
J
2
1
0
1
8/1/2019
EL5.5GC July2019
7/6/2019 7/11/2019 7/16/2019 7/21/2019 7/26/2019 7/31/2019
EL5.5GC August 2019
8/6/2019 8/11/2019 8/16/2019 8/21/2019 8/26/2019 8/31/2019
101 City Hall Plaza, Durham, NC 27701 919.560.1200 DurhamNC.gov follow Us @CityofDurhamNC
00 a

e
6
5
s 4
a
d
O
NO
3
NO
0
J
2
1
0
1
9/1/2019
a
6
5
s 4
a
O
NO
3
NO
0
J
2
1
0
-1
10/1/2019
EL5.5GC Se pte m be r 20 19
9/6/2019 9/11/2019 9/16/2019
EL5.5GC October 2019
9/21/2019 9/26/2019 10/1/2019
10/6/2019 10/11/2019 10/16/2019 10/21/2019 10/26/2019 10/31/2019
101 City Hall Plaza, Durham, NC 27701 919.560.1200 DurhamNC.gov follow Us @CityofDurhamNC
00 a

e
7
6
5
s 4
a
d
O
NO
3
NO
0
J
2
1
0
-1
11/1/2019
a
7
6
5
s 4
a
d
O
NO3
NO
0
J
2
1
0
-1
12/1/2019
EL5.5GC November 2019
11/6/2019 11/11/2019 11/ 16/2019 11/21/2019
EL5.5GC December 2019
11/26/2019 12/1/2019
12/6/2019 12/11/2019 12/16/2019 12/21/2019 12/26/2019 12/31/2019
101 City Hall Plaza, Durham, NC 27701 919.560.1200 DurhamNC.gov follow Us @CityofDurhamNC
00 a