WATER QUALITY MONITORING


What is water quality monitoring?

Getting organised

The monitoring plan

Five kinds of surveys

Setting goals

Quality of data

Fixing water quality problems

Staying credible

What to measure

Activities for schools


What is water quality monitoring?


Water quality monitoring means examining the physical, chemical and biological characteristics of water - observing how these factors change over time, and over different positions along a water body.

Physical characteristics include, colour, smell, water velocity, temperature, acidity and turbidity (ie the quantity of suspended solids in the water giving it a murky or cloudy appearance). Important chemical characteristics are the levels of nitrates, phosphates and salt in the water.

The physical characteristics of rivers can change rapidly and over a wide range. Seasonal changesin rainfall make rivers run fast or slow, pollution can be a shockwave of chemicals let loose in the night, gone the next day. The kinds of plants and animals living in the water are a better long term index of the health of the water. Some creatures are easier to measure than others and are useful biological indicators. One useful index of river water condition is derived from the presence or absence of macroinvertebrates (animals, not including fish and frogs, larger than 5-mm in length). In New Zealand rivers, water bugs such as dragonflies, beetles, and other insects, have different tolerances to pollution. By identifying which ones are present, and which ones are absent, it is possible to determine how much pollution has been in the water during the length of time it took the creatures to become established and grow up there.

By making records of these, and other factors, at a number of points along local waterways community groups build up a picture of local water quality and pinpoint problem areas. Collected data may then be exchanged through electronic networks with neighbouring groups to create a picture of water quality through an entire catchment - and beyond.

Water quality monitoring programs are set up as a means of identifying problems and working out ways to improve conditions in the waterways. Depending on the problem, enhancement of waterways might be accomplished by tree planting and fencing of some areas of river banks to exclude stock, reducing the community's use of fertilisers and pesticides, or constructing artificial wetlands downstream of agricultural settlement ponds.


The monitoring plan


After you have organised your Water Watch group and discovered what is already known about your river, the next step is to devise a monitoring plan.

The monitoring plan determines where, what, how, and how often you will take measurements or observations of the waterway. It depends on the concerns of people in your community, what monitoring is already being done, and observations made during your baseline survey.

Like all plans, the monitoring plan must be reviewed and revised as new discoveries are made. In the beginning, it is best to start with easily obtained observations and measurements.


Five Kinds of Survey


1. The preliminary survey is a critical first step. Working out where you will take your measurementsmakes all the difference in the world to the ease and validity of your efforts. It's a question of checking out the river for the best and most meaningful sites, ones that are easy to get to, can be found again with little effort, and safe. The preliminary survey is done in two parts, first using maps and asking questions of people and councils in the catchment area to find out what is already known, and second, visiting likely places to survey and recording general information about them.

2. A baseline survey establishes what the health of the river is now so later surveys can tell if water quality is improving, or getting worse. It's important to take measurements that can be replicated in later surveys. Since the data is the foundation (baseline) for future comparisons, sampling sites should be selected to represent the complete range of conditions in the catchment.

3. A water quality standards survey determines whether the water meets water quality standards for designated uses (such as swimming) and values (such as aquatic habitat or aesthetics). Obtain copies of the Ministry for the Environment's Water Quality Standards for information on the standards that apply to the waters you are monitoring.

4. A pollution sources survey measures the affects of people on the waterway. Generally, three sites should be chosen. Immediately upstream of the impact. Immediately downstream of the impact where the water has mixed, and even further downstream, where the water has at least partially recovered from the impact.

5. An event survey measures the amount of sediment, nutrients, salt or litter that is washed into a waterway during heavy rain. Measurements are taken before, during and after a storm.


Setting monitoring goals


Hold a meeting of your whole community group and, using maps and information from the preliminary survey, consider questions such as:

what do we know about the water body's uses and values?

is it safe to swim in?

does it meet state water quality standards?

does it support aquatic life?

what human impacts threaten the health of the water?

where are the information gaps that our monitoring could fill in?

what should be our long and short-term goals?

what types of samples should we take?

where and how often should we sample?

who will use the information we collect?

how, and how often, should we report?

how can we get a good training program run by skilled and experienced people?

Quality control


How accurate do your measurements need to be? Organisation of a Quality Control Program will be very important to the usefulness of your information. The quality of data is described in terms of:

Sensitivity (the smallest unit measured). This is obtained from the manufacturer of any special equipment used.

Precision (the ability to repeat the same measurement). Check this by taking more than one sample and comparing the results.

Accuracy (how close your measurement is to a known reference). Systematically check on the accuracy of your results by testing standard solutions of known concentrations from scientific supply companies or by monitoring alongside professional staff working in your area.

Comparability (how well samples taken from one location can be compared to those taken at another). Select your sampling sites so they can be easily compared. This is especially important when doing a pollution sources survey or recording the impact of an outfall.

Completeness (the number and variety of samples needed to meet your objectives). The key here is to take enough samples but not more than you need to find out what you really want to know. Taking too many samples or measurements can be as much of a problem as taking too few. A good detective goes after the important clues.

Compatibility (the way you enter data onto forms or into a database so it can be used by others). This can be critical. Work with professionals to find out how they record data in your catchment area. Set up your database to match theirs so they can use your data and you can use theirs. It is best to actually use the same software programme and get a copy of their spreadsheet or database files to use as a template.

Go over your work

Check your results against those obtained by council or NIWAR professionals for a similar waterway or at other locations in your waterway. If the results are similar to the professionals, you are probably doing OK.

If your data shows a water quality problem, or is well outside the limits of other data, check over your work carefully. Go back to the site and take replicate samples. Do you get the same results again?

Check to be sure the results are not a result of incorrect recording (such as an impossible reading like pH 15 or 125 degrees C.)

Could the samples have been contaminated in some way?

Could you be measuring some unusual natural weather or water flow conditions?

Show your work to at least two experts and clarify any seeming contradictions or confusing facts. If you have made a mistake, be the first to admit it, then correct it. If the result is valid, find out what is causing the problem. You may need help here from your city, district, or regional councils.


When there is a problem - negotiate


There may be occasions when a problem can be traced to a particular source such as high nutrients from a piggery, a sewage overflow, or an unauthorised industrial emission. In these situations it is important that a non-confrontational approach is adopted. Select a capable person to coordinate contact between your group and those responsible for pollution. The following procedure should be followed:

The monitor who identifies a problem, contacts the coordinator.

The coordinator confirms the monitor's observations (perhaps by re-testing)

If the coordinator determines that a problem does exist, he or she either makes personal contact with the person responsible, or presents a written report to the responsible agency - whichever seems most likely to result in positive long term change.

Whatever decision is made, the aim is always to achieve a 'win-win' outcome for the waterbody and the person responsible for the pollution.

Where the cause of the problem can be traced to the activities of a group; such as householders, factory owners or shopkeepers:

try to involve all the affected parties in a discussion of the issue

explain your findings and state the need for action in terms that make clear the community benefits.

separate the personalities from the issue and listen to all sides

talk about real needs, not positions

invite those involved to help you to develop solutions that protect resources and meet everyone's needs.

monitor the results of any agreed changes and renegotiate if necessary. If an agency has been notified, the coordinator should contact the agency within a specified time, to make sure the problem has been investigated and corrected.

publicise any improvements in water quality that result.

Remember, if people have willingly worked together to arrive at a solution, they are more likely to make that solution work.


Staying credible, interesting and dynamic


A credible program incorporates regular reviews and analyses of training, satisfaction and morale as well as technical matters like monitoring techniques, equipment performance, data recording and reporting.

Use newsletters, phone calls and easily understood and useable reports to keep your group informed of results, program progress and events. Most important, be sure to publicise any action or improvement in water quality that results from your monitoring.


References: Waterwatch Australia


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