Field Water Sampling


The Earth’s global cycles describe the movement of elements between reservoirs in the biosphere, lithosphere, hydrosphere and atmosphere. The length of time an element will remain within each reservoir varies, depending on the processes it moves through. For example, a carbon atom in carbon dioxide can cycle through the surface ocean within a day or can become trapped in the lithosphere as fossil fuel for millions of years.

An outside pond or a local water body provides a great opportunity to investigate aquatic plants and animals. Through water samples collected from the field, you can learn more their important role in the global cycles, as well as the evolution of life from simple organisms.

A natural water body in a public reserve

Collecting a good field water sample is straight-forward as shown in our Field Water Sampling video. Two sampling methods are demonstrated in the video and other methods can be sourced from the internet.

Equipment

Specialised equipment is available for collecting field water samples; however, you can construct a basic collection device by firmly attaching a bottle to a long pole (as shown in our video).

Site selection

Your collection site should have easy access to the water body. Suitable locations include public parks, your school, or a backyard pond. If the water body is on private property, make sure you have access permission from the owner.

Compile notes on the site and the surrounding land use, including photos. These notes can be detailed or brief, depending on your water sampling requirements, and are useful for future reference. Examples of site notes are available from Waterwatch Australia

Sampling

These guidelines are suitable for sampling from the edge of the water body, not for entering the water.

  • Safety is the first priority. Consider the following:
  • Make sure the water you are sampling is clean and free of algal masses. It should both appear and smell fresh, free of toxins and excessive rubbish.  
  • Sample in groups of at least two people. Let others know where you are going and when you will be sampling.
  • Ensure you have ready access to first aid kits and mobile phones.
  • Wear appropriate clothing – long pants, sun protection and closed-in shoes or boots.

Safely collecting a sample from the edge of a water body

Be mindful of the impact of your sampling activity on the local plants and animals. Minimise disturbance to their habitat both in the water and in the surrounds. Return aquatic animals back to the water as soon as possible.

Decide at what location in the water body you want to collect your sample and approach it from downstream. To minimise disturbance to your sampling location, scoop the water in a direction from downstream to upstream. Start by rinsing out your collecting bottle, using the following method: Turn the bottle underwater into the water flow away from you, collect a small sample halfway between the water surface and the bed, and swirl it around your bottle. Discard this water back into the stream, downstream of where you want to collect your sample. This will prevent disturbance of the sediment at your sampling point. Our video demonstrates how to do this.

Collect your samples and place into your sample jar. Remember to label your jar with the date, site, collector, and any other information you would like to include for future reference.

Example of a labelled water sample

When you have finished your sampling, do a final check to make sure you have collected all your belongings, leaving only your footprints behind.

Next steps

  • Design your own water sampling activity to test abiotic and biotic water quality parameters. Visit Waterwatch Australia for more details on these parameters and how to do this.
  • Investigate the health of your local water body and the possible impacts from the surrounding land use with WASP.
  • Test the effect of fertiliser on the growth of algae. Some ideas can be found in the WASP STEM Resources.
  • Look into Citizen Science projects involving water quality monitoring and see how you can contribute.