17.8  Sampling methods for bacteriological testing

During the course of an investigation into a disease outbreak or as part of routine monitoring, you may be required to take water samples to be sent for microbiological or chemical analysis. It is important that samples are taken carefully and correctly to ensure they can be used for an accurate assessment of the condition of the source. When water samples are collected for analysis, you should take care to ensure that there is no external contamination of the samples. Glass bottles, rather than plastic, are best used for sampling. Both bottles and stoppers (caps) must be sterilised. Bottles should be clearly labelled with the place where the sample was taken and the date. You should be able to obtain sample bottles from your regional public health microbiology laboratory or your local environmental health office.

You may need to take water samples from a tap, river, lake, water tank or dug well, and each has a slightly different procedure to follow.