I-16_FieldMeasurementsAndObservationsSOP_FINAL_20200720 signed

CITY OF
DURHAM
City of Durham, North Carolina
Department of Public Works
Stormwater and GIS Services
Water Quality Unit
Title: Standard Operating Procedures for Field Measurements and
Observations
Version: 1.1
Date: July 20, 2020
Approvals
Approved by: l�i/�� e/� Date:
Michelle Woolfolk, Water Quality Manager
July 20, 2020
Approved by: loazd Date: July 20, 2020
Paul Wiebke, Assistant Director for Stormwater & GIS Services

Revision Record
Revision
Date
Updated by
Description of change
1.0
03/21/2019
Shannon Hauschild,
Initial draft
Dave Milkereit
1.1
04/17/2020
Joseph Smith
Minor Edits
Christine Cailleret
Distribution
Current copies of this approved SOP should be provided to the following positions with the City of
Durham Stormwater and GIS Services:
• Water Quality Manager
• Assistant Water Quality Manager
• Environmental Planning and Compliance Senior Analysts
• Environmental Planning and Compliance Analysts
• Environmental Planning and Compliance Coordinators
• Environmental Planning and Compliance Specialists
• Temporary Environmental Planning and Compliance Specialists or other staff assigned to the
project
The current SOP should also be provided to any contractors performing these procedures on behalf of
the City of Durham Stormwater & GIS Services.
Abbreviations
[IS/Cm
Microsiemens per centimeter
DO
Dissolved Oxygen
COD
City of Durham
mg/L
Milligrams per liter
NTU
Nephelometric Turbidity Unit
PPE
Personal Protective Equipment
PW
Public Works
QA/QC
Quality assurance/quality control
QAPP
Quality Assurance Project Plan
SIDS
Material Safety Data Sheet
SOP
Standard Operating Procedure
S.U.
Standard Units
SW
Stormwater
WQ
Water Quality
WQU
Water Quality Unit
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Contents
Title: Standard Operating Procedures for Field Measurements and Observations...............................1
Approvals..................................................................................................................................................1
RevisionRecord........................................................................................................................................
2
Distribution...............................................................................................................................................
2
Abbreviations............................................................................................................................................
2
Procedures....................................................................................................................................................
5
Purposeand scope...................................................................................................................................5
Methodsummary.....................................................................................................................................5
Healthand safety warnings......................................................................................................................5
General safety considerations..............................................................................................................5
Personal protective equipment............................................................................................................6
Chemicalsafety....................................................................................................................................7
Cautionsand interferences......................................................................................................................8
Personnel qualifications and responsibilities...........................................................................................8
Equipmentand supplies...........................................................................................................................9
Methods...................................................................................................................................................
9
CloudCover........................................................................................................................................10
FlowSeverity......................................................................................................................................10
StaffGauge Readings..........................................................................................................................10
AirTemperature.................................................................................................................................11
WaterTemperature...........................................................................................................................11
pH 12
SpecificConductance.........................................................................................................................12
DO Saturation and Concentration......................................................................................................12
Turbidity 13
Water Transparency (Secchi Depth)...................................................................................................14
OtherData..........................................................................................................................................15
Data and records management..............................................................................................................16
Quality assurance and quality control(QA/QC)..........................................................................................16
References..................................................................................................................................................16
Appendix1. Field Sheet Example................................................................................................................17
Tables
Table 1 Significant Figures Conventions .................
7
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Figures
Figure 1 Reading a staff gauge ..................................
Figure 2 HACH 2100Q Portable Turbidimeter...........
Figure 3 Secchi disk submerged in water using rope
11
13
15
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Procedures
Purpose and scope
The purpose of this Standard Operating Procedure (SOP) is to establish uniform procedures for the
Water Quality Unit (WQU) staff to follow while collecting field measurements and observations
associated with water quality monitoring. The procedures outlined in this document apply to all WQU
monitoring activities that involve collecting field measurements and observations, such as ambient
monitoring, special studies, outfall screening, and illicit discharge investigations. This SOP is designed to
describe procedures for staff to follow to obtain accurate and reliable measurements and observations
while in the field.
Method summary
Field measurements and observations are performed in conjunction with various sampling activities.
This SOP summarizes general procedures for collecting field measurements and observations, but staff
should refer to project -specific documentation (such as Quality Assurance Project Plans, additional SOPS,
or study plans) for additional guidance before the collection of field data. Electronic field meters (either
multi -parameter or single parameter) are used to measure in -situ water quality parameters of air
temperature, water temperature, dissolved oxygen saturation, dissolved oxygen concentration, specific
conductance, and pH. A Portable Turbidimeter is used to measure turbidity. Staff gauges are used to
measure stream stage height. A Secchi disk is used to measure Secchi depth, a measurement of water
transparency. Other field conditions that are evaluated by observation include cloud cover, flow
severity, sampling proximity to thalweg, precipitation in the previous 24 hours, and any other notable
condition that may influence results for field measurements or lab analyses. Additionally, photos and
GPS coordinates are taken as needed. All measurements and observations are documented on field
forms at the time of collection.
Health and safety warnings
General safety considerations
The WQU conducts sampling throughout the City of Durham and surrounding areas at times and places
where medical facilities may not be readily available. All employees must receive detailed instruction
and follow safety precautions when using equipment and hazardous materials to prevent injury. "Safety
first" must always be the rule.
All employees should receive a copy of the Department of Public Work's Safety Operating Procedures
(City of Durham 2017) and current Safety Policies (City of Durham Employee Policies S-201— S-208)
upon hire. Any injuries or incidents should be documented and recorded following City and Department
policies. The priority should be to provide appropriate care (First Aid or emergency treatment) to the
injured employee; the second priority is to notify the appropriate supervisor.
While the remainder of this section summarizes some of the more common hazards encountered during
fieldwork, all employees are expected to review and comply with all City procedures and policies.
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One of the most prevalent situations encountered by field staff is walking over uneven and often wet or
muddy terrain while carrying heavy or bulky equipment. Streams in Durham are also often deeply
incised, with steep banks and soils that are clay -based and slick when wet. These conditions increase
risks for slips, trips, and falls. Many sites require working in urban areas where hazards such as roadway
traffic, domestic animals, and possibly wild animals can make access dangerous. In -stream hazards such
as glass shards, construction debris, medical waste, and miscellaneous trash are commonly present.
Staff must be vigilant to take proper precautions to decrease the chance of injury. Working in streams
also exposes staff to uneven, slick, or unstable substrates and potentially high flows, all of which can
challenge balance and lead to falls and even potential risk of drowning. Water depth and velocity should
always be considered during site reconnaissance and fieldwork.
Weather forecasts should be consulted before field sampling activities. Weather (such as heavy rain,
thunderstorms, tornados, lightning, high winds, and excessive heat or cold) can create unsafe
conditions. In certain cases, such as heavy rain or excessive heat or cold; additional personal protective
equipment (PPE) may be required. Fieldwork may need to be modified to minimize risks, such as falls,
heat stress, or hypothermia due to weather conditions. Staff should immediately seek shelter or
reschedule fieldwork if there are active thunderstorms with lightning or other severe weather. Weather
conditions are particularly critical if staff will be accessing sampling sites by boat when high winds or
water levels can make boating unsafe.
Personal protective equipment
The following PPE is required for field staff under most conditions encountered during sampling, though
they may be modified based on current weather conditions, project requirements, and site -specific
conditions.
• Appropriate footwear - chest waders, hip boots, knee boots, or steel toe work boots. The
primary purpose of protective footwear is to protect feet from abrasions and crushing injuries.
Field staff should not sample in shoes that do not cover the entire foot (such as sandals) or
shorts, neither of which offer full coverage of feet and lower legs. If monitoring activities require
wading in a stream or other water bodies, then waders, hip boots, or rubber knee boots should
be worn to keep staff dry to reduce risks of cold -related stress and to reduce the potential
exposure of staff to pathogenic organisms and other contaminants that are commonly found in
urban water bodies. During the winter and spring, neoprene waders can provide additional
protection from cold temperatures and reduce risks associated with hypothermia. However,
during warmer periods, waders can increase the risk of heat -related illnesses. These additional
risks can be reduced by staff by minimizing the time spent in direct sunlight, ensuring they stay
hydrated, and taking frequent breaks (including removing waders) as needed to ensure their
safety.
• Long pants protect the lower legs from abrasions and reduce the potential for bites from ticks,
insects, and snakes.
• First aid kits should be carried by all field staff during all fieldwork. Staff should also be familiar
with the location of additional first aid kits in vehicles and labs.
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• High visibility vests or other clothing must be worn when working alongside roads, bridges, and
in the right-of-way.
• Appropriate eye protection should be worn as required by the SDS when using chemicals, or
when performing activities that may present a danger of a foreign object entering the eye (e.g.,
use of power tools).
• Long gloves/gauntlets may be helpful under certain situations, such as during cold weather
work to reduce cold -related stress, when sampling below a known discharge to minimize
exposure to pathogens, or to reduce the risk of cuts in the presence of hazards (glass shards,
etc.) within the stream.
• A hat, such as a baseball cap or wide -brimmed hat, helps to shade the head and face, which
helps reduce the potential for sunburn and heat -related illnesses.
• Sunblock/sunscreen reduces the risk of sunburn.
• Insect repellent is important for preventing vector -borne diseases and reactions (including
allergic reactions). Mosquitoes and ticks are very prevalent in Durham and can be active at any
time of the year, and therefore insect repellent containing DEET or another proven chemical
repellent should be worn during all field activities. Staff should check themselves for ticks at the
end of each field day and document any embedded ticks found.
• Poison ivy pre- or post -exposure treatment is necessary for staff that are prone to allergic
reactions to poison ivy or other plants. Affected employees should minimize exposure whenever
possible and take steps to remove irritating plant oils from their skin and clothes as soon as
possible after exposure to reduce the risk of allergic reactions. Soap -and -water is often effective
for removal, though may not feasible under field conditions. There are commercial products
(such as Tecnu) that are more easily used under field conditions. All staff should be mindful of
transferring oils from their clothing to vehicle seats, etc., which can be a potential source of
exposure for other staff.
• Orange safety cones should be used behind vehicles that are parked on the road or in the right-
of-way and the flashing warning lights on the City vehicle should be on to alert other traffic.
• Rain gear (jacket and pants) should be worn to keep staff dry and reduce risks of cold -related
illnesses.
• Personal flotation device (PFD) is required to be worn and fastened during boating activities or
when working over water (such as sampling from a bridge or top of culvert). For boat work,
additional safety equipment (flares, fire extinguisher, horn, etc.) may be required and will be
described in the project QAPP or study plan.
Chemical safety
City staff must follow any applicable City guidance and/or policies for activities such as chemical storage
and handling and the storage of preserved specimens. Chemical handling, storage, and disposal should
comply with requirements in associated Safety Data Sheets (SDS). When sampling unknown substances
in the field, staff should assume they are hazardous and wear appropriate PPE, such as disposable nitrile
gloves. The Stormwater Laboratory (SW Lab) is located in the Annex Building in City Hall and is equipped
with safety equipment such as eyewash stations and fully stocked first aid kits in case of emergency.
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Currently, laboratory sample processing and analyses (including chemical and biological samples) are
not performed by City staff, but rather by private Contractors. Contractors are responsible for following
all appropriate laws and regulations as well as any internal safety procedures.
Cautions and interferences
To support a high level of confidence in field readings, meters must be properly calibrated before use.
Additionally, proper post -sampling checks provide additional assurances of accuracy. Because
temperature extremes can influence meter post -checks, meters should not be transported in open truck
beds. Users should consult the following documents for further guidance on meter usage and
maintenance:
• Standard Operating Procedures for Water Quality Field Meter Calibration and Maintenance
• User manuals for handheld meters and turbidimeters
Care must be taken to avoid damaging meter sensors. Always use YSI handheld meters with probe
guards in place. When not in use, probes (with probe guard in place) must be covered with a moistened
plastic cover when in the field.
When using galvanic DO probes, field staff should ensure sufficient streamflow is present but should
also avoid flow with excess sediment and debris that could damage the meter. The DO sensors used by
the WQU typically use either optical or polarographic technology. To assure the accuracy of
measurements taken with polarographic probes, a minimum flow of 6 inches per second must pass over
the probe. Optical sensors do not require a minimum flow.
Turbidity sample vials must be rinsed three times with native water before collecting the sample for
analysis with the Portable Turbidimeter. Sampling should avoid any suspended sediment or surface
debris. Invert the vial multiple times to homogenize the sample, but take care to not create air bubbles,
which may result in an erroneous reading. Vials with samples must be wiped clean and dry with a lab
wipe (Kimwipe) before being placed in the turbidimeter. Sample vials must also be clean and free of
scratches or other defects.
While using the Secchi disk, the user should remove their sunglasses and/or hat. The Secchi depth
measurement should always be taken from the shaded side of the boat in an area with minimal waves
or ripples. If any of these conditions are not met, it should be documented on the field sheet or in the
field notes.
Personnel qualifications and responsibilities
All WQU staff conducting water quality monitoring should be familiar with and follow the procedures
described in this document and related SOPS. Field data collections are conducted by at least one
experienced Water Quality staff member. Staff members unfamiliar with sampling procedures should be
accompanied by at least one experienced WQU staff member until they are competent in the
procedures described in this document and other related WQU SOPS. Responsibilities for QA/QC of field
measurements and observations can vary by project, but should be described in the project study plan,
Quality Assurance Project Plan (QAPP), or other project documentation.
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Equipment and supplies
Specific equipment needed for field measurements and observations will vary based on project needs,
but may include:
• Field sheets and waterproof pen
• Standard Operating Procedures for Field Measurements and Observations SOP
• Other relevant SOPs and documentation
o Meter maintenance and calibration
o Department of Public Works Safety SOP (City of Durham, 2017)
o Project study plan, QAPP, or other SOPs
• Portable Turbidimeter with:
o Sample cells
o Spare batteries
o Kimwipes (lens wipes)
• Appropriate field meter(s) (multi -parameter or single parameter)
• Spare batteries
• Tools needed for in -field maintenance (screwdriver, etc.)
• Weighted Secchi disk with rope
• Measuring tape or pocket rod (measures to nearest 0.01 ft.)
• GPS unit with batteries
• Camera
• Clock or watch for telling time
Methods
Complete all required pre -field activities, such as meter calibrations, immediately before beginning
fieldwork. All observations and measurements should be recorded immediately after collection on
project field sheets or in a field notebook. In recording field data, samplers must follow the significant
figures convention listed in Table 1, unless otherwise directed.
Table 1 Significant Figures Conventions
Parameter
Reporting precision (# decimal places)
Turbidity
Nearest 1 NTU
Temperature
Nearest 0.1 °C
DO saturation
Nearest 1
DO concentration
Nearest 0.1 mg/L
Specific conductance
Nearest 1 µS/cm at 2S'C
pH
Nearest 0.1 SU
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Cloud Cover
Cloud cover is a visual estimate of the extent of cloud cover.
1. Sampling staff must determine if cloud cover at the moment of field measurements falls into one of
the following categories:
• Sunny (less than 25% cloud cover)
• Partly Cloudy (between 26 to 75% cloud cover)
• Overcast (greater than 75% cloud cover)
Flow Severity
Flow severity is an observation of relative flow intensity and stage height at a sampling site. Use prior
knowledge or field indicators (such as bankfull height or debris lines), current stream stage, and current
stream velocity to determine relative flow conditions based on the following 5-point scale:
1. Channel is dry and/or has disconnected pools
2. Flow is lower than normal
3. Flow is normal
4. Flow is higher than normal
5. Channel is at (or above) flood stage or bankfull condition
"Normal" streamflow may vary throughout the year, so consider seasonal variability when determining
Flow Severity.
Staff Gauge Readings
Staff gauges are used for relatively long-term monitoring of water height (stream stage). They are
securely attached to a stable support, such as rebar, a post, or a culvert. The WQU generally uses "Type
C" staff gauges, which allow measurement of water level (stage) to the nearest 0.01 ft. To read a staff
gauge:
1. The graduated face of the staff gauge must be cleared of all debris, algae, or other obstruction
impeding a clear view of gauge marks.
2. The observer must be positioned directly in front of the graduated face of the gauge, with the
observer's view close to the level of the stream surface.
3. The observer must remain still long enough for the water surface to settle.
4. The gauge is read where the water surface touches the nearest graduated mark.
5. Each top or bottom edge of the graduation mark represents 0.01 ft.
6. Gauge readings are taken to the nearest 0.01 ft. (see Figure 1).
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7
5 -
----- water bevel------------ -_
4
3 _
Each top or
bottom edge of a
graduation mark
=
represents .01ft.
I
In this case, the
staff gage
.�
measurement is
1.44 ft.
Figure 1 Reading a staff gauge
7. In some cases, the water level may drop below the bottom or rise above the top of the staff
gauge. Use a pocket rod or rigid ruler marked in 0.01 ft. to measure the elevation of the water
above or below the staff gauge. Record water levels that are below the bottom of the gauge as a
negative value. If the water level is above the top of the stream gauge, add the reading from the
pocket rod to the maximum value on the staff gauge and record the sum.
8. Note any damage or changes to the installation of the gauge, such as being knocked off vertical,
dented, bent, etc., in field notes.
Air Temperature
Air temperature is measured with an electronic meter or bulb -type thermometer in degrees centigrade
(C°). To measure air temperature:
1. Turn the meter on (if using).
2. If using a meter, remove the probe's rubber cover to allow airflow over the temperature sensor.
If using a bulb thermometer, hold or hang it to allow air to flow around the bulb.
3. Wait for the temperature value to stabilize.
4. Record the air temperature on the field sheet to the nearest 0.1 degrees Centigrade.
5. Between sites, store the electronic meter in the appropriate manner, and out of direct sun.
Water Temperature
Water temperature is measured with an electronic meter in degrees centigrade (C°). To measure water
temperature:
1. If not already on, turn the meter on.
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2. Place the probe in the waterbody at a point that is representative of the sampling location and
at an appropriate depth.
3. Wait for the temperature value to stabilize.
4. Record water temperature on the field sheet to the nearest 0.1 degrees Centigrade unless
project documentation specifies otherwise.
pH
pH is a logarithmic measure of hydrogen ion (H +) concentration in a solution and is a measure of how
acidic or basic the sample is on a scale of 0 to 14 with 7 as neutral. pH is reported in standard units (s.u.).
An electronic field meter is used to measure pH. The pH sensor is comprised of a glass electrode that
measures electrical potential to calculate proton concentration. The glass electrode is very delicate, and
care must be taken when deploying the sensor to avoid damaging it. To measure pH:
1. If not already on, turn the meter on.
2. Place the probe in the stream at a point that is representative of the sampling location and at an
appropriate depth.
3. Wait for the pH value to stabilize.
4. Record pH on the field sheet to the nearest 0.1 standard unit unless project documentation
specifies otherwise.
Specific Conductance
Conductivity is defined as the ability to carry an electrical current. In water this electrical flow is the
result of electrolytic conductance most commonly caused by salts in the solid, liquid, and dissolved
states. More specifically, specific conductance (SC) is conductance corrected to a standard temperature
of 25°C. Specific conductance is measured in micro -Siemens per centimeter at 25°C (µS/cm @25°C).
Standardized temperature allows for meaningful comparisons of conductivity data. Specific conductance
is commonly used as a measure of total dissolved solids (TDS) in a solution.
To measure specific conductance:
1. If not already on, turn the meter on and allow it to stabilize.
2. Many field meters report both uncorrected conductivity and SC. If the meter being used can
report specific conductance, confirm that the meter has been set up to report SC at 25°C.
3. Place the probe in the stream, at a point that is representative of the sampling location and at
an appropriate depth.
4. Wait for the specific conductance value to stabilize.
5. Specific conductance should be recorded on the field sheet to the nearest 1 µS/cm unless
project documentation specifies otherwise.
DO Saturation and Concentration
Dissolved oxygen (DO) measures the amount of gaseous oxygen dissolved in an aqueous solution. DO is
measured as a concentration in milligrams per liter (mg/L) and as percent saturation (%).
Water Quality Unit Staff use electronic field meters that can measure DO using either optical or
polarographic DO probes. Polarographic probe technology employs a process that consumes local DO.
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Therefore, the use of polarographic units requires a continuous minimum flow of 6 inches per second
over the DO probe. The optical probe does not require flow and can be placed in stagnant water.
DO should be measured as follows:
1. If not already on, turn the meter on. Depending on the meter type and manufacturer, the meter
may need several minutes to repolarize the probe.
2. Place the probe in the stream.
3. If a polarographic probe is being used, ensure there is a minimum flow over the probe of 6
inches per second. This can be achieved by:
a. Placing probe in a representative area of the waterbody at an appropriate depth with
adequate flow.
b. Move probe back and forth perpendicular to the direction of flow. Movement must be
fast enough to create an artificial flowof 6 inches per second, but not so fast as to
introduce air into the water being measured.
4. Wait for the DO readings to stabilize.
5. DO saturation must be recorded on the field sheet to the nearest 1 percent unless project
documentation specifies otherwise.
6. DO concentration must be recorded on the field sheet to the nearest 0.1 mg/L unless project
documentation specifies otherwise.
Turbidity
Turbidity is a measure of light scattered by suspended particulates in the water. This is a proxy measure
of water's relative cloudiness or clarity. Water Quality staff use a portable turbidimeter (see Figure 2 for
an example) to measure turbidity.
Figure 2 HACH 2100Q Portable Turbidimeter
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The turbidimeter measures light transmission through a glass vial of sample water.
To measure turbidity:
1. Open the turbidimeter kit and remove a sample vial. Ensure the vial is free of scratches or other
defects. The turbidimeter kit can remain in the vehicle while a sample is retrieved from the
sample site.
2. At the sample site, select a sample point that is representative of the sampling location.
3. Rinse the vial three times with native water.
4. Fill the vial with a sample at the depth specified in the project documentation. Avoid introducing
debris or suspended sediment that is not representative of the sample site.
5. Turn on the turbidimeter by pressing the "On/Off" button. Ensure that there are no error
messages and that the empty turbidimeter is reading 0 NTU.
6. Before inserting the sample vial into the turbidimeter's sample chamber, first wipe the sample
vial using a Kimwipe to remove any water droplets. Next wipe the vial with the felt cloth and 1-
2 drops of silicone oil. The outside of the vial must be free of water droplets, fingerprints, and
other interferences.
7. Immediately before measurement, invert the sample vial three times to ensure sample
homogeneity. Avoid generating bubbles in the sample, as these will interfere with the
measurement.
8. Insert the sample vial into the turbidimeter's sample chamber. The arrow on the sample vial
must line up with the arrow on the body of the turbidimeter. Close the sample chamber lid.
9. Press the "Read" button.
10. A measure will be indicated on the turbidimeter screen once the sample has been measured.
11. Turbidity is recorded to the nearest 1 NTU.
12. Turn off the turbidimeter
13. Remove the sample vial from the sample chamber and close the sample chamber lid.
14. Dump the sample vial and return it to the turbidimeter kit.
15. Close the lid to the turbidimeter kit and safely store it in the vehicle.
Water Transparency (Secchi Depth)
A Secchi disk is used during lake sampling to collect a measurement of water transparency (see Figure 3
for an example). The Secchi depth measurement can also be used to estimate the depth of the photic
zone.
To collect the Secchi depth:
1. The rope attached to the Secchi disk should be accurately marked in graduated meters. The first
meter should have 0.1 m graduations, while subsequent meters should have 0.5 m graduations.
Check that the rope is firmly attached to the disk and that there are no signs of stretching or
knotting that may affect the accuracy of the marked graduations.
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2. The observer's eye level should be one meter above the surface of the water, making sure that
sunglasses are removed and that the Secchi depth is being recorded from the shaded side of the
boat.
3. Slowly lower the Secchi disk into the water until the disk is no longer visible. Record the depth at
which the disk becomes no longer visible.
4. Lower the disk just below the previous depth, then slowly begin to raise it toward the surface of
the water.
5. Record the depth at which the disk becomes visible.
6. Calculate the average Secchi depth measurement from the two previous readings and record it
on the field sheet to the nearest 0.5 m, unless project documentation specifies otherwise.
Figure 3 Secchi disk submerged in water using rope
Other Data
Site photos and GPS coordinates are gathered depending on the requirements of specific sampling
projects.
1. For photos, give adequate contextual references to indicate the approximate location from
which the photo was taken. Name files with date, site name and an indication of an upstream or
downstream view (e.g. "US" or "DS") or other descriptors.
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2. Geographical coordinates (latitude and longitude) are typically collected with a recreational
grade GPS receiver, such as a Garmin eTrex. Coordinates are collected using the NAD 1983
Coordinate System in decimal degrees. In general, coordinates should be recorded to 4 decimal
places, unless project documentation specifies otherwise. Waypoint names must include the
sampling site name. Refer to the GPS receiver's manual for usage instructions.
Data and records management
Field data are recorded on field sheets. See Appendix 1 for an example of a typical field sheet, though
the exact format will vary by project. In the office, data from field sheets are entered into a spreadsheet
template and uploaded to the data Web Portal. See Standard Operating Procedures for Use of the Water
Quality Web Portal (City of Durham, 2018a). Photos are saved in the appropriate location in the Water
Quality server folder. Refer to project documentation (particularly QAPPs) for additional requirements
for data and record management.
Data logged electronically should be maintained in an unaltered format in the project folder, this file will
be labeled according to the following format: "yyyymmdd_SiteName_TypeOfResults_Project.csv". Any
modifications of this data should only be made to a copy of the original file, labeled:
"yyyymmdd_SiteName_TypeOfRes ults_Project.csv _edited".
Quality assurance and quality control (QA/QC)
Care must be taken to accurately record field data. When field sampling is conducted by a team, field
sheets must be reviewed in the field by all sampling team members to verify accuracy and
completeness. Proper meter calibration, post -check, and maintenance are important QA/QC activities.
The Standard Operating Procedures for Water Quality Field Meter Calibration and Maintenance should
be consulted for proper calibration, post -check, and maintenance procedures. Additional QA/QC
requirements, such as field audits, will be described in project specific QAPPs.
References
City of Durham. 2017. Safety Operating Procedures. City of Durham, Department of Public Works.
City of Durham. 2018a. Standard Operating Procedures for Use of the Water Quality Web Portal.
Stormwater and GIS Services, Water Quality Unit.
City of Durham. 2018b. Standard Operating Procedures for Water Quality Field Meter Calibration and
Maintenance. Water Quality Unit.
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Appendix 1. Field Sheet Example
Month: February Day: 1 Date: 2/6/2018 Field staff:
Rain cast 24 hrs? y N
Dist
Site# Lab# Air H2O
SC
from
Samp Cloud Flow temp temp DO
DO pH [us/cm Turb
Thwg
Location Time method cover sev i°Cj [°C] %
[mg/L] (s.u.) @ 25°C] (NTU)
Thy?
fftl
EL8.6SECUT 193
S. Ellerbe Cr Tri buta ry at
Y N
Foster St and Hurrt St
Comment:
EL7.1EC 230
Eller be Cr at W ClubBlvd
Y N
and Acadia St
Comment:
EL13EC 41 QC
EllerbeCr at Glenn Rd
Y N
Comment:
LR9.6LR 180
Little R at Patrick and
Y N
Johnson Mill Rds
Comment:
Samp method: DD=Direct dip; S - Scoop; P - Pump; 0- Other
Cloud cover: Sun - Sunny (�5%); PC - Partly cloudy (26r75%); O - Overcast (>75%)
Flow sev: Enter value from 1 [dry] to 5 (flood)
City of Durham, WQ Unit, Field Measurements and Observations SOP, v. 1.1 DRAFT Page 17 of 17
06/05/2020