Field Procedure Guide for Tier 1 Monitoring - 2015

NATIONAL ESTUARIES
MONITORING PROGRAMME
Field Procedure Guide for Tier 1
Monitoring
2015
Prepared by: Jafta, N., Van Niekerk, H., Cilliers, G. and Majola, S.
For Resource Quality Information Services
Department of Water and Sanitation
for use during field work
TABLE OF CONTENTS
1.
2.
OVERVIEW AND INTRODUCTION ........................................................................... 1
PART 1: PREPARATIONS PRIOR FIELD SAMPLING ............................................. 2
2.1. THE SAMPLING SITES .......................................................................................... 2
2.2.
THE EQUIPMENT AND CONSUMABLES .............................................................. 2
2.3.
CHECKING AND MAINTENANCE OF EQUIPMENT FOR FIELDWORK ............... 6
2.3.1.
Operation of Equipment ................................................................................... 6
2.3.2.
General calibration precautions and maintenance ........................................... 7
2.3.3.
Dissolved Oxygen (membrane sensors and optical sensors) ........................... 8
2.3.4.
pH .................................................................................................................... 9
2.3.5.
Electrical Conductivity .................................................................................... 10
2.4.
FINAL PREPARATIONS FOR THE FIELD ........................................................... 11
3.1.
PART 2: FIELD SAMPLING .................................................................................... 12
FIELD READINGS AND MEASUREMENTS ......................................................... 12
3.
3.1.1.
Visual Observations ....................................................................................... 12
3.1.2.
Transparency or Secchi Depth Measurement ................................................ 12
3.1.3.
Other Physico-chemical Variables ................................................................. 13
3.2.
4.
SAMPLE COLLECTION, PREPARATION AND STORAGE PROCEDURE .......... 13
3.2.1.
Nutrients ........................................................................................................ 13
3.2.2.
Phytoplankton Biomass ................................................................................. 14
3.2.3.
Microbial Counts ............................................................................................ 15
PART 3: POST FIELD ACTIONS AND SAMPLE ANALYSES ................................ 16
4.1. TRANSPORTATION OF SAMPLES ..................................................................... 16
4.2.
DATA MANAGEMENT .......................................................................................... 16
ANNEXURE A: CALIBRATION RECORD SHEET ............................................................. 18
ANNEXURE B: SAMPLING EQUIPMENT AND PROCEDURE CHECK LIST ................... 19
ANNEXURE C: RECORD SHEET FOR FIELD OBSERVATIONS ..................................... 20
ANNEXURE D: LIST OF LABORATORIES TO BE CONTACTED FOR THE ANALYSIS OF
SAMPLES .......................................................................................................................... 21
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1. OVERVIEW AND INTRODUCTION
This is a procedure guide for field sampling associated with the National Estuaries
Monitoring Programme (NESMP).
The NESMP monitoring is based on a 3 tiered approach, starting from the most basic
national sampling to estuary specific protocols.
 Tier 1 will address the most basic water quality measurements, with the lowest
production level of the biota (phytoplankton and microbes). The monitoring will be
based on a build up of baseline data and for the understanding of long-term trends of
the different types of estuaries. Monthly field sampling is a requirement for this
Tier, unless at a later stage it is deemed to not yield significant differences in
results (data) and has been proved to not be feasible.
 Tier 2 is the Resource Directed Measures’ (RDM) Ecological Water Requirements
(EWR) determination protocol. It looks at the estuarine ecosystem’s abiotic and biotic
relationship in more detail, to holistically understand the ecological health of each
system. This type of monitoring is to be done every 3 to 5 years depending on
estuary specific conditions and preferably to establish a long term trend analysis of
ecosystem health in a specific estuary, to report on regional and national estuarine
health; to feed into preliminary and comprehensive Reserve determinations; and to
audit the success of Reserve implementation. This monitoring should make use of
the RDM Monitoring protocol (WRC, 2003).
 In tier 3, situation specific information is collected with the following objectives in
mind: proactive conservation planning; surveys for comprehensive Reserve
determination purposes; reactive investigation of specific anthropogenic impacts e.g.
artificial mouth breaching, pollution incidents, fish kills etc.; reactive audit of the
success of remediation actions; and reactive investigations of natural phenomena
e.g. floods, droughts etc. A monitoring or sampling protocol for this Tier has not been
developed as it will be dependent on the objectives of the initiation of this Tier of
estuary monitoring.
This guide covers the sampling/monitoring of the Tier 1 parameters of the programme. There
is already a guide that has been compiled for the RDM monitoring protocol (CSIR, 2003),
which would be Tier 2 of the NESMP. As Tier 3 monitoring is a combination of variables from
Tiers 1 and 2, this and the RDM guide should be used
There are various steps to be followed when executing field sampling procedures. It is
important to ensure that everything is in order before going to the field; i.e. all the required
equipment is available and packed, you are familiar with the operation of all the equipment
and you have checked that they are in good working condition.
There are certain steps to be followed before going to the field, at the sampling sites (in the
field), and after the sampling has been conducted. These steps and sampling procedures
are explained in the subsequent sections under the following headings, of which Part 1 is a
preparation for fieldwork, Part 2 is for during fieldwork and Parts 3 and 4 after the fieldwork:
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Part 1: Preparation for fieldwork
Part 2: Sampling and Sample Preparation
o Sample collection, preparation and storage for/or until analysis
o On-site Measurements
o Permanent Loggers
Part 3: Post field Actions and Analyses
Part 4: Data Management
2. PART 1: PREPARATIONS PRIOR FIELD SAMPLING
2.1. THE SAMPLING SITES
Before the first sampling trip, it is advised that the sampling team familiarise themselves with
the location of the sampling sites along the estuary. The team must have gone to the estuary
before or have familiarised themselves with the estuary and the chosen sites on a map,
image (i.e. using Google Earth) or loaded the coordinates on a GPS. For the first few
fieldtrips, it is advised that a laminated image or map, on which the sites are marked, is
taken with, if no GPS coordinates exist yet. It is, however, strongly advised that a GPS is
used to reach the points to ensure consistency.
2.2. THE EQUIPMENT AND CONSUMABLES
The tools needed are summarised in Table 1 below, depending on the estuary requirements.
Table 1: Materials, Equipment, Consumables
Description
Materials, Equipment, Consumables
Calibration
Standards
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Portable hand
filter apparatus
for Chlorophyll-a
and Box of GF/C
Filter papers
Hydrophilic PVDF
0.45 μm pore-size
syringe filters on
a Syringe
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AquaRead’s
meter and probe,
with electrodes
on right. A
different but
similar
instrument can
also be used.
In-situ water level
and conductivity
probe (AquaTroll)
with USB cable
(Troll COM)
connected, with,
on the side, the
Cal Cup
(calibration
bottle) and the
Twist-Lock
Hanger for
sealing the top
part of the probe
and to suspend
the probe with a
cord/rope/wire. A
different but
similar
instrument can
also be used.
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Secchi Disc with
marked rope
Sampling Bottles
and Tag for
labelling
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2.3. CHECKING AND MAINTENANCE OF EQUIPMENT FOR FIELDWORK
Most of the equipment needed for the sampling will be supplied by the Department of Water
and Sanitation (DWS), the Resource Quality Information Services (RQIS) unit. The
continuously needed materials will be couriered or delivered to the relevant persons or
organisations on a monthly basis or as a large stock to last a few months.
2.3.1. Operation of Equipment
In most cases, the equipment that will be supplied for the field measurements is
Aquameter’s meter and probe (the handheld instrument) and In-situ Inc.’s Aquatroll, Rugged
Troll, Barotroll (the in-situ instruments), or CTD. Most of the guidelines for the operation,
maintenance and calibration of the handheld and in-situ instruments form part of the
packaging of the instruments as hard copies or are easily available from the manufacturers’
software or program discs as user guides. It is therefore crucial for the samplers to
familiarise themselves with these guidelines, especially in the case of a different instrument
being used.
2.3.1.1.
Initial Set Up and Preparation of the Handheld
AquaRead’s meter and probe, or a similar instrument, i.e. YSI, is used to take
measurements of physico-chemical variables in the estuary water column. The Aquaprobe
AP-700 and meter will be used mostly in the National Estuaries Monitoring Programme. The
different electrodes in the probe that will be used to measure the variables are shown in
Table 1 above.
On the first occasion of using any instrument, it must be initially set up for use in the field and
the first step is usually to install the software before plugging the meter to your computer.
Once the installation is done, connect the probe to the meter and switch on the meter and
give it time to stabilise. In the case of the AquaRead’s meter being used, the built-in GPS will
first look for satellites while the variables will be stabilising. Once stabilised, use the side
arrows to browse the recordings and settings of the instrument, press the OK button to
select and ESC to go to a previous screen. MENU is for calibration, settings and data
logging. The M+ is for taking or logging a measurement once the probe is in a solution or in
the water. To recall previously logged data, press MR.
It is also important to have a look at the settings, especially the date and time, units of
measurement, and the language and to set these properly before taking any measurements.
For the units settings, make sure that the units for DO (dissolved oxygen) are in mg/L, for EC
(electrical conductivity) on Ref 25oC, for Temp (temperature) in oC, for SAL (salinity) in PSU,
as well as ensuring that the pH is selected instead of ORP (Oxidative Redox Potential).
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2.3.1.2. Initial Set Up and Preparation of the in-situ/permanent
loggers
In-situ measurement instruments have a probe that gets permanently housed at certain sites
along an estuary to take real time measurements of the water level, temperature and
conductivity, set at preferred intervals.
Since there are several different types of in-situ measurement instruments, even with the
NESMP, there are more than two types used. It is thus recommended that the
manufacturer’s guide be consulted for the instructions on setting up, calibration,
maintenance and data retrieval.
It is however, very important to ensure that the instrument gets calibrated and
maintained regularly. It is properly installed at a suitable site to avoid theft and
exposure. The site must be suitable for continuous data logging, i.e. does not dry up,
whilst also not vulnerable to being swept away in periods of high rainfalls.
2.3.2. General calibration precautions and maintenance
These are just general calibration precautions and maintenance that applies to all water
quality loggers or probes installed or used in estuarine systems, outlined by Harold van
Niekerk (RQIS). Please note that you should always refer to the instrument’s manual for
product specific requirements.
2.3.2.1.




You need to always use fresh buffers (DO NOT pour the buffer back into the bottle
after use). Therefore, after calibrating in a buffer it must be thrown out!
Note the date on which the buffer was opened and check the bottle expiration date.
During use, close the buffer bottle immediately after pouring out the amount that you
need (to prevent carbon dioxide exchange).
Generally pH 4 and 7 buffers expire within 3 months of being opened and pH 10
buffer within 1 month of opening. The reason for this is that they get bacterial
contamination and they absorb carbon dioxide once opened.
2.3.2.2.



Buffers and solutions
Probes
When not in use, the probes should be stored in a moist condition but NOT in
distilled water, make use of tap water or the water from the river that you are
sampling. It is important that the glass membrane is stored moist in order to
maintain hydration; however, the probes should not be submerged in water.
If the pH probe is stored for more than 3 months, it should be removed from the YSI
instrument and stored in the solution supplied with the probe (KCl solution).
Always have spare pH probes, oxygen membranes, etc. available. Loggers can be
out of order for months if spares are not available.
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2.3.2.3.



The pH, oxygen and conductivity probes should be calibrated at least once a month if
they are permanently deployed.
Alternatively, if they are used less frequently then they should be calibrated every
time before use in the field or in the lab, depending on the circumstances.
A chlorophyll probe will not reflect accurate concentrations if it is not calibrated for the
specific water type, algal composition and algal distribution. If close to actual
concentrations are required, the probe should be calibrated each time before use and
when algal composition or distribution changes.
2.3.2.4.

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




Things to avoid!
Storing the electrode/probe dry or in de-ionized water.
Stirring the sample or buffers using the electrode (to prevent damage to the probe).
Re-using buffers.
Polishing a pH bulb (it could BREAK) - if need be you should clean it gently with
tissues.
Assuming that the pH, oxygen and conductivity calibration procedures are simple.
They are in fact complex and need to be done properly.
Leaving LCD screens in direct sunlight or exposed to excessive heat.
2.3.2.5.

Calibration frequency
Other
Ensure that the battery life of the instrument is sufficient for the period of intended
use and that the batteries are replaced when they’re depleted.
If needed, try and keep spare batteries in the instrument bag.
WQ probes are highly affected by mud or silt build up. If sufficient recourses are not
available to keep logger housings and boxes clean, it is better not to install WQ
loggers. An incorrect result can be more problematic than no result at all.
2.3.3. Dissolved Oxygen (membrane sensors and optical sensors)
2.3.3.1.




Calibration precautions
Before calibration, the oxygen membrane should be visually inspected to make sure
that the oxygen membrane has been installed correctly (refer to the User Manual), as
well as to make sure that the membrane is not damaged. If the membrane has been
damaged, it must be replaced.
If the fluid under the membrane has air bubbles, then the fluid and membrane should
be replaced. This does not apply to optical sensors!
Oxygen is calibrated in moist air. Only approximately 5mm of water should be at the
bottom of the calibration cup (NB: the probe should not touch the water).
If the copper coloured metal of the probe beneath the membrane seems dirty it
should be lightly sanded using the sandpaper that comes with the oxygen membrane
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
kit BUT you must be careful not to touch the membrane surface. This does not apply
to optical sensors!
Always ensure that the rotating cleaners on the optical sensors are not parked on the
membrane.
Always ensure that the calibration cup is loosely attached when used during
calibration.
During calibration, the DO sensors should not be in contact with the water.
2.3.3.2.


Maintenance
If you get an ‘out of range’ auto response during calibration, check that the
membrane is not in contact with the water in the calibration cup. For models using
membranes, also check for bubbles, sufficient KCL solution or a torn membrane.
As a general rule the membrane disk on the optical sensors should be replaced
annually to ensure optimum performance.
2.3.4. pH
2.3.4.1.








Calibration precautions
Always calibrate with at least two buffers, preferably pH 4 and 7.
Calibration in the pH 7 buffer should be performed first.
pH 10 buffers absorb carbon dioxide and are, therefore, unstable and not
recommended for use in field calibration.
It is recommended that calibration be done with a buffer that is at the same
temperature as the water that is to be measured hence field calibration is
recommended. Buffer can be put in a plastic bag and submerged for ten minutes in
the water to be tested.
If calibration is carried out in laboratory or enclosed environment, please ensure that
temperature is kept constant at all times.
Ensure that you rinse calibration bottle and probes with water before and after
calibration to avoid contamination.
If you get an ‘out of range reading’, do not accept it. First check for obvious reasons
e.g. that the correct value was entered for the pH buffer solution currently being
used.
You can use the pH millivolt readings to determine the health of the probe. Consult
the user manual for guidance. For YSI pH probes the acceptable millivolt readings for
each buffer is as follows:
pH 4 = +180 (±50mv)
pH 7 = 0 (±-50mv)
pH 10 = + - 180 (±50mv)
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The difference between the two millivolt readings should be between 165 and 180. The
probe should be discarded once below 160.
2.3.4.2.

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


Maintenance
The probes should be stored in a moist condition. Therefore, after use you should
pour some water in the calibration cup (no more then 5-10mm) - NOT distilled water
though.
Used calibration fluids should be discarded.
If the probe is to be stored on the instrument for longer than 3 months without being
used, it should be removed from the instrument and stored in the KCl storage
solution provided with the probe.
The calibration cup and the probes should be rinsed and cleaned after using them.
Probes generally have a lifespan of two years if used in environmental conditions.
After installation of a new probe the “out of range” reading can be accepted during
the first calibration.
2.3.5. Electrical Conductivity
2.3.5.1.






Calibration precautions
Do not get confused with the EC units. During calibration the specific instrument
might require that a different EC unit be used than what is indicated on the calibration
solution bottle.
o Example: YSI requires that the EC value for calibration is in mS/cm although
the calibration standards we use are mostly in µS/cm. This means that if the
bottle indicates 12 880 µS/cm or 1413 µS/cm you will have to divide it by
1000 and use 12.88 mS/cm or 1.413 mS/cm respectively for calibration. On
the other hand, DWA WQ guidelines use mS/m which requires an additional
conversion.
When filling the calibration vessel before calibration, make sure that there is enough
buffer solution in the calibration cup to cover the entire conductivity cell.
After placing the probe in the calibration solution, agitate the probe to remove any
bubbles in the conductivity cell – NB: remember the warning about not stirring with
the probe.
During calibration, the sensors must be allowed time to stabilize - approximately 60
seconds is usually adequate.
Low concentration conductivity standards are susceptible to contamination and their
use is not recommended unless extra care is taken to rinse the calibration vessel and
probe compartment with the standard solution to be used prior to calibrating. YSI
mostly recommends using a mid-range calibration standard of approximately 10 000
µS/cm.
The two standards that are used in RQS are: 1413µS/cm and 12880µS/cm.
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2.3.5.2.

Maintenance
Clean regularly with a small brush or cloth to avoid fouling. There are no special
requirements since EC probes are fairly robust.
Even though different instruments may be used, the most important thing is to ensure that
the electrical conductivity gets calibrated at 12880 µS/cm, the pH at 7 first then 4.01, and the
dissolved oxygen at 100% moisture. Ensure that you rinse the probes thoroughly with water
(not de-ionised) after each calibration so as to not contaminate the next calibration. Discard
any calibration fluid after use.
Please follow below links for specific product requirements and calibration manual:

AquaRead AP-700: http://www.aquaread.com/portofolio/ap-700-ap-800/

YSI 556: https://www.ysi.com/File%20Library/Documents/Manuals/655279-YSI-556Operations-Manual-RevD.pdf

Aqua Troll 200: https://in-situ.com/wp-content/uploads/2014/11/Aqua-TROLL-100200_Manual.pdf
2.4. FINAL PREPARATIONS FOR THE FIELD
Ensure that the following are ready before going to the field:
 A cooler box with ice bricks, for the chlorophyll-a (phytoplankton biomass), nutrient
and microbial samples
 Enough clean sample bottles are available, labelled and ready for the collection of
samples for nutrients (minimum 200mL), and chlorophyll-a (500mL), per site. These
bottles can be supplied by DWS: RQIS
 Enough sterilised bottles are available for the collection of microbial samples. These
bottles will be supplied by the laboratory that does the microbial analysis and thus
need to be collected every time samples are submitted to the lab.
 The following are important to have on the final labels – the name of the
estuary/system, site numbers, the sampling date and time, and the volume of filtered
water in the case of the chlorophyll-a samples
 The Whatman glass fibre (GF/C) filter papers for chlorophyll-a
 The filter unit and pump for chlorophyll-a
 Enough foil is available to cover the GF/C filter papers, with the chlorophyll-a
samples. Or, the 25mL glass tubes filled with 10mL ethanol have been provided by
DWS to store and preserve the chlorophyll-a filter paper samples (stored and
transported in a dark and cool container).
 The syringe and enough syringe filters for the nutrient samples, to be used after the
field collection. The syringe filters must be hydrophilic, 0.45 μm pore-size, and have a
25mm diameter.
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The Aquameter’s probes have been calibrated (see section 2.3 above for set-up and
calibration) and its cord has been marked at 0.25m distance intervals. The intervals
may be 0.5m as well, depending on the depth of the estuaries in your area
The Aquameter’s batteries have been checked and replaced if required
A record sheet has been filled in, with the date of the calibration of the probes and
the readings that were recorded before calibration. An example of a record sheet can
be found in Annexure A.
The Secchi Disk is available and the 10cm and 1m distance intervals have been
properly marked and are visible on the rope
Writing material (pencil and paper or waterproof writing board) is available
An equipment and procedure checklist has been compiled for before, during and after a field
sampling trip, see Annexure B.
3. PART 2: FIELD SAMPLING
3.1. FIELD READINGS AND MEASUREMENTS
3.1.1. Visual Observations
Record your observation of the surrounding environment on a record sheet, which should
also be sent to DWS with the other data. An example of the features to consider and to look
out can be found in Annexure C, which can be printed out and used in the field.
3.1.2. Transparency or Secchi Depth Measurement
A secchi disc measurement determines the clarity/transparency of the water, which then
inversely relates to the turbidity (DWAF: NEMP, 2002). Do the following to measure it:






Use a secchi disc with an attached rope that has marked distances of 10 cm and 1m
intervals
Slowly lower the disc into the water column, with the painted, black and white, side of
the disc facing up.
Lower the disc while holding and slowly releasing the rope with the sun behind you
as reflections off the surface can influence the visibility of the disc.
Watch the disc slowly disappear into the water.
Record the distance on the rope at which the black and white paint of the disc is just
visible in the water column.
Can also be used to determine the end depth at each site.
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3.1.3. Other Physico-chemical Variables
The AquaMeter/probe is used in most estuaries in the NESMP, but other instruments are
also acceptable, i.e. the YSI multiprobe. The most critical measurements are Temperate,
Electrical Conductivity, Dissolved Oxygen (mg/l), and pH and the instrument must be
calibrated before use in the field.
The procedure for using the probe is as follows:













If using AquaRead’s aquameter, switch on the by pressing the red button,
Wait for the GPS to search for the satellites and for the variables to stabilise,
Remove the pH/ORP storage cap from the pH/ORP electrode
Once stabilised, lower the probe end of the instrument into the water column,
Start taking measurements, starting with the surface (0 m) measurement,
Once in the water, give the probe time to stabilise its taking of readings of the
environment,
When the readings have stabilised record the readings on a record sheet or field
measurement sheet, and then press the M+ button to take a reading at this depth
with the instrument,
Lower the probe to the next depth of measurement and record another reading (both
manually on paper and with the instrument),
The depths of measurement depend on the systems overall depth. Very shallow
systems could be measured at 0.25m depth intervals, medium depth systems could
be at 0.5m intervals and deep to very deep systems could be at 1m to 2m intervals.
the decision is estuary specific, as long as it is consistent per site,
Then, follow the above procedure to take readings at every set interval to the bottom
of the water column,
Follow the above steps for each site.
In between sites, the Aquameter and probe must be kept in its box, for protection
purposes and ALWAYS ENSURE THAT WHENEVER THE PROBE IS NOT IN USE,
THE DAMP PH/ORP STORAGE IS FITTED ON THE PH/ORP ELECTRODE.
After use, the probe and cord must be rinsed thoroughly with freshwater, kept in its
box and stored away properly.
3.2. SAMPLE COLLECTION, PREPARATION AND STORAGE PROCEDURE
3.2.1. Nutrients
For nutrient samples, the following must be conducted at each site:
3.2.1.1. Sample collection



Rinse the collection bottle, two times, with estuary water.
Collect a sub-surface sample by lowering a labelled collection bottle into the water,
covering your arm as far as the elbow.
Fill up the bottle with sample.
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
Keep bottle with the unfiltered water sample in a cooler box with ice until the samples
can be filtered.
3.2.1.2. Preparation and Storage







On the same day after the field sampling, when at the lab or work station, filter the
collected samples through the hydrophilic PVDF 0.45 μm pore-size syringe filters,
using a syringe.
Filter by first drawing the sample from the bottle with the syringe, attach the filter disc
(syringe filter), press out the sample in the syringe, through the filter, into a new
labelled 350 mL bottle, and keep repeating this until the filtered sample is enough in
the new bottle. Close the bottle with its cap.
Leave some space in the new bottle to allow for expansion.
Make sure there is a labelled tag tied around the bottle, indicating the monitor
(organisation), the date and time of collection, that it is a sub-surface sample (0m
depth), that it is a nutrient sample, and the site number/name.
Repeat the above steps for each site, taking care to use a new filter disc with each
site’s sample and to label each sample properly.
Store the filtered samples in the freezer, until they can be sent to a lab for analysis.
The filtered and frozen water samples will be analysed for DIN (Dissolved Inorganic
Nitrogen) (- NO3, NO2, NH4) and soluble reactive phosphorus (SRP) (- PO4).
3.2.2. Phytoplankton Biomass
The measurement of chlorophyll-a will be used as a measure of phytoplankton biomass in
the estuary/water column. Follow this procedure for the sampling:
3.2.2.1. Sample collection


At each site, rinse the sample collection bottle twice (500mL or above) with site water
and collect a sub-surface sample by filling up the bottle.
Ensure the bottle is labelled, or has a labelled tag, indicating the system name, site
number, date and time of collection. Keep the water sample in the dark in a cooler
box with ice (if the filtering will be done at a later stage).
3.2.2.2. Preparation and Storage





Either at the field, if feasible, or back at the work station, filter the water sample.
Get the filter unit ready by placing a GF/C filter paper in the middle unit, in between
the top and bottom halves of the unit and then gently screw together the two halves
of the unit.
Fill the top part of the filter unit to the 250 mL mark.
Connect the pump and gently create a vacuum, by slowly pressing on the pump, not
exceeding the 15 cm mark of the pressure gauge of the pump.
The water will be slowly sucked through the filter paper.
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Once the entire sample has filtered though, remove the bottom part of the filter unit. It
is advisable to keep this water aside for the nutrient sample, the pre-filtration eases
the strain on the syringe filters.
If the water is not too turbid, place back the bottom unit connecting it with the top part
and filter another 250 mL of water, for a 500 mL sample.
If the sample is too turbid for another 250 mL or after the full 500 mL has been
filtered, carefully remove the top section of the filter unit, then the filter paper, without
touching the sample on top. Fold the filter paper in half and roll it, with the sample
side inward.
Either, place the filter paper in the glass bottle containing ethanol, screw the lead
tight (ensuring the undeliner is in place), and seal around the lead with Parafilm.
Or, cover the filter paper with a piece of tinfoil.
Ensure the volume of water filtered (250 or 500 mL) is now written on the labels,
together with the site name and number, monitor, date and time of collection, and 0m
for sub-surface grab.
Store the tinfoil, samples in the freezer until analysis.
The samples in ethanol must also be stored in the dark, in a cool environment, until
analysis.
It is important that the samples do not interact with light and warm conditions as the
chlorophyll will degrade and not be representative.
3.2.3. Microbial Counts
Water samples need to be collected for the analysis of microbes in the water column. The
microbes are Enterococci and Escherichia coli (E. coli).









One sample will be collected per site, at the sub-surface level (depth).
Do not rinse the sterile microbial collection bottle.
Keep the sample bottle closed until it is to be filled.
Immediately prior to filling, remove the cap. Ensure that the inner surface of the cap
and neck of the bottle do not come in contact with any non-sterile surfaces, including
your hands.
Submerge the labelled sample bottle into the water column and collect approximately
500 mL of sample for the Enterococci and E. coli counts, leaving at least 2.5cm of
headspace to facilitate mixing by shaking prior to analysis.
When collecting the sample, drag the bottle away from you.
Cap the sample bottle immediately.
Indicate the date and time of sample collection, the site name/number on the tag.
Place the bottle with the sample in an iced cooler box until it can be couriered for lab
analysis, preferably on the same day.
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4. PART 3: POST FIELD ACTIONS AND SAMPLE ANALYSES
4.1. TRANSPORTATION OF SAMPLES
The collected water samples for chlorophyll-a, microbial and nutrient analysis will have to be
sent to an approved laboratory. The microbial samples need to be sent to the laboratory
within the same day of collection. There are a number of laboratories across the country in
the different regions which have been contracted to do the analysis for the microbial
samples. A list of these laboratories is in Annexure C. When transporting the samples, they
have to be kept in a cooler box with ice.
As for the nutrient samples, they can be frozen until they are forwarded to a laboratory for
analysis. This freezing time should be as minimal as possible. If there is a contracted
laboratory in your region rather send the samples to the laboratory as soon as possible.
Keep the samples in a cooler box with ice during the transportation to the laboratory.
The chlorophyll-a samples can be sent to the Resource Quality Information Services (RQIS)
laboratory in Pretoria. A courier service has been contracted by the Department of Water
and Sanitation for the transportation of these samples. Place the foiled-wrapped sample filter
papers in a cooler box with ice and get the courier company to deliver the samples to RQIS.
The samples should preferably not be sent from Thursday onwards. If the sampling was
done on a Thursday or Friday, rather keep the samples in the freezer, away from any light,
until the following Monday to courier.
To find out more about the courier services to use in your region, contact RQIS for further
details.
4.2. DATA MANAGEMENT
To download data from the handheld instrument, e.g. Aquaread’s Aquameter, connect the
USB cable to the meter, connect the instrument to a computer with the instrument’s
software, switch on the instrument and ensure USB Connected is displayed on the
instrument. Open up the software and, in the case of use of the AquaRead, follow as
displayed in Figure 3 below of the AquaLink programme/software. Click Upload data from
Aquameter, choose the data you would like to upload and then export data as excel file.
Choose a folder to save the exported data in your computer. When saved, the data can then
be view on excel.
On excel, the data will need to be cleaned up a bit. Insert columns for the estuary name, site
name/number (e.g. ZI-1), depth of measurement, and Secchi depth. The sampler will know
the sites sampled based on the displayed dates and times of measurements. This is crucial
to do before sending the data to RQIS as the sampler knows best the sites and depths they
measured.
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Figure 3: Representation of steps to follow in AquaLink for the data download
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ANNEXURE A: CALIBRATION RECORD SHEET
Organisation Name: ____________________________ Calibration Date: _________________
Calibration Time: ___________________________
Variable
Measured
Value
Before
Calibration
Measured
Value After
Calibration
Instrument Model: ________________
First Measured
Field Value After
Calibration
Comments about Calibration
EC (µS/cm)
pH 7
pH 4
DO (mg/L)
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ANNEXURE B: SAMPLING EQUIPMENT AND PROCEDURE CHECK LIST
TO DO BEFORE GOING TO THE
FIELD
Checked
TO TAKE WITH (PACK) AND TO USE AT THE FIELD
Setting up of AquaMeter
GPS, or marked Map, landmarks, for location of sites
Calibration Standards and
calibration of for AquaMeter
Calibrated and set up AquaMeter with clear distance interval
marks on cord
Record sheet of the AquaMeter
calibration results and date (see
Annexure A)
Label (on tag) bottles for nutrient
and microbial samples
Cut and label foil pieces for the
chlorophyll-a filter papers
Calibration standards and calibration of Aqua Troll (the in-situ
instrument)
Checked
TO DO AFTER FIELD SAMPLING AND
SAMPLE COLLECTION
One or two syringes and one hydrophilic PVDF
0.45 μm pore-size syringe filters (yellow discs)
Clean labelled 350mL bottles for filtered nutrient
water samples. One per site and separate from
the
Unfiltered labelled 350mL sample bottles
collected for nutrients for filtration into new
labelled 350mL bottles.
Record sheet of the AquaTroll calibration results and date
Laptop or notebook for Aqua Troll data download
Secchi disc with marked rope
One 500mL, or above, bottle for collection of water samples for
filtration for chlorophyll-a
One Filter Unit and one Pump for water filtration for
chlorophyll-a
Fridge for the storage of the microbial sample
bottles.
Freezer for the storage of the foil-wrapped filter
papers for chlorophyll-a and the filtered sample
bottles for nutrients
Rinsing of the AquaMeter’s rope and probe with
freshwater
Computer for the AquaMeter data download and
management
GF/C filter papers for chlorophyll-a. One filter paper per site
Labelled foil for covering filter paper with sample. One per site
Cleaned Labelled 350mL bottles for collection of unfiltered
water samples for nutrients. One bottle per site
Labelled collection bottles for microbial samples (E. Coli and
Enterococci).
Covered cooler box with ice, big enough to store the
chlorophyll-a samples in foil, the unfiltered nutrient sample
bottles, and bottles of the collected microbial samples
Paper and a pencil for recording of observations and readings
from the AquaMeter
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Checked
ANNEXURE C: RECORD SHEET FOR FIELD OBSERVATIONS
SYSTEM NAME:
Sampling Date:
Mouth Status (if not
permanently open
system)
Start Sampling Time:
Open
Sampler:
□
□
□
□
□
□
□
Closed
□
Tide
In
River Flow
None
Trickle
Rain 24hrs
Yes
No
Rain 7Days
Yes
No
Cloud cover
100%
≥70%
Wind Strength
None
Breeze
Wind Direction (N,
NE, E, SW, etc.)
Water Colour
Clear
Water Level
High
Out
Greenish
□
Overtop
□
□
Moderate
□
Overtop
□
□
Neap
Medium
Spring
Strong
□
□
□
□
□
≤70-40%≥
Slightly Turbid
Medium
□
□
□
□
□
Turbid
≤40%
Strong
□
□
0%
Gale
□
□
Very turbid
Low
□
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ANNEXURE D: LABORATORIES TO BE CONTACTED FOR THE ANALYSIS OF SAMPLES
AREA
LABORATORY
FOR ANALYSIS
OF
Pretoria
Resource Quality Information
Services
Chlorophyll-a from
all estuaries
Stellenbosch
Water Analytical Laboratory cc
(LAB NOT
ESTABLISHED/CONTRACTED)
George
Pathcare George
Port
Elizabeth
Pathcare PE
Enterococci and
E. Coli from west
coast
Enterococci and
E. Coli from
southern cape
Enterococci and
E. coli from
eastern cape
Enterococci and
E. coli from
eastern cape
Enterococci and
E. coli from
northern KZN
Kei Water
CONTACT PERSON
CONTACT
NUMBER
FAX NUMBER
E-MAIL ADDRESS
Nolusindiso Jafta
012 808 9511 or
082 875 9015
Marianne Franck
021 883 8905 or
083 607 8159
Karen Cronje or Carike Woest
044 803 8222
kcronje@pathcare.co.za
carike.woest@pathcare.co.za
Karen Cronje or Carike Woest
041 391 5700/22
kcronje@pathcare.co.za
carike.woest@pathcare.co.za
Malgas Booi
047 531 3973
keiwater@interkom.co.za
Swaswa Ntlhoro
035 902 1049
035 902 1107
sntlhoro@mhlathuze.co.za
TO BE
ESTABLISHE
D/CONTRACT
ED
TO BE
ESTABLISHED/CONTRACTED
jaftan@dwa.gov.za
021 883 8905
mfranck@walab.co.za
Richards
Bay
Mhlathuze water
Durban
EThekwini Municipality or
Umngeni Water
Enterococci and
E. coli from
southern KZN
TO BE
ESTABLISHED/CONTRACTED
TO BE
ESTABLISHED/C
ONTRACTED
Western
Cape
Centre For Scientific and
Industrial Research (DURBAN)
Nutrients from
south to west
coast estuaries
Loyiso Magqi
031 242 2398
LMagqi@csir.co.za
Eastern
Cape and
KwaZulu
Natal
Centre For Scientific and
Industrial Research (DURBAN)
Nutrients from
south to east
coast estuaries
Loyiso Magqi
031 242 2398
LMagqi@csir.co.za
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Contact details
For more information with regards to sampling manual and technical aspects of water quality
probes, please contact any of the following people:
Department of Water and Sanitation
Resource Quality Information Services
Moloto Road
Roodeplaat Dam
Pretoria
0001
VanNiekerkH2@dws.gov.za
Cell: 082 808 9843
Harold van Niekerk
Gerhard Cilliers
CilliersG@dws.gov.za
Cell: 082 880 3964
Nolusindiso Jafta
Sibusiso N. Majola
JaftaN@dws.gov.za
Cell: 082 875 9015
MajolaS@dws.gov.za
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