Around the state, Environment Protection Authority Victoria’s (EPA) authorised officers and environmental scientists take water samples to detect cases of pollution and monitor the health of Victoria’s waterways.
Learn about the equipment and processes involved in taking a water sample and why parameters such as salinity and dissolved oxygen are important indicators of water quality.
Water sampling is just one of the ways EPA is striving for a healthy environment for all Victorians.
00:26 Collecting a water sample
01:09 Using a field meter
Hi there, I’m Jodi I’m an authorised officer with the Environmental Protection Authority of Victoria, also known as EPA. Today I’m going to check the quality of the water in this creek to see if there’s any pollution we need to investigate.
When EPA receives a report of water pollution from a member of the public we may respond by sending someone like me an authorised officer out to investigate further. Our environmental scientists also test water quality around Victoria as part of ongoing environmental monitoring programs.
I need to collect a sample using this sample pole and the sample bottle. The sample pole lets me grab a sample out of the creek without disturbing the bottom. We just dip the bottle in and fill it up with the water. The sample is put on ice in an esky and sent off to an independent laboratory.
At the lab they do a number of different tests on the water to check for different types of pollutants.
Depending on the creek or the environmental problem this could include pollutants such as oils,
metals, hydrocarbons or pesticides.
The lab will send us their sample results. We’ll assess those results against various guideline values that we report against. This will let us know whether any of those results were above levels considered safe.
I also use a field meter to measure various parameters directly in the waterway. I place the probe in the water and move it around until the readings stabilise.
So this number here is the amount of dissolved oxygen in the waterway and that can vary a lot over twenty four hours. Really low levels of dissolved oxygen can mean that the water quality is poorer than what it should be and that could be the result of pollutants, blue-green algal blooms or droughts.
So this number here is salinity which is a measure of how much salt is in the water. We would normally expect something below 1,500 but currently rating around 400,
which is great for a little freshwater creek like this.
The reading at the bottom of the screen is pH. It’s a measure of how acidic or basic the waterway is.
We’d normally expect a result between about six and eight. We’re currently reading seven which is what we’d expect for a waterway like this.
So all of the field results we got were normal and when we get the samples back from the lab we’ll have a look at them and that will identify if there’s any pollution we need to further investigate.
EPA’s authorised officers and environmental scientists undertake water sampling all across Victoria. It’s just one of the ways that EPA is striving for a healthy environment for all Victorians.