There are two ways in which chlorine can be added to drinking water, to help make it safe to drink.

1. Chlorination is achieved by adding only chlorine to drinking water. This method is generally suited to shorter distribution systems as chlorine naturally breaks down quickly.

2. Chlorimination, which is adding chlorine and ammonia together. Chloramine is much more stable and is better suited for longer distribution systems such as in Aireys Inlet.

In chloraminated systems, we combine ammonia and chlorine to form a long-lasting disinfectant that keeps our water safe to drink.

Nitrification is a natural process that can sometimes occur in chloraminated systems, where the ammonia breaks down to nitrate and nitrite.

When this happens, it can become harder to keep enough disinfectant in the system to maintain water quality. This can also lead to changes in pH, smell or taste.

To prevent this, Barwon Water monitors the network closely and when early signs of nitrification are detected we take action, like mains cleaning.

To treat nitrification, we temporarily change how we disinfect the water.

Instead of using chloramination (chlorine and ammonia), we switch to chlorination (chlorine only) for a short period. By temporarily removing the ammonia, we stop the nitrification process and allow the system to reset.

We will also carry out flushing through the system to help move the chlorine through the system quickly and reduce how long the cleaning program needs to run.

Once completed, ammonia dosing will restart and we will return to chloramine disinfection as usual.

This approach is safe, effective, and commonly used in water systems when needed.

The project will not interrupt water supply and will not impact on water flow or pressure.

The water will remain safe to drink. You may notice a temporary change in the taste and smell of your water, particularly as we switch back to our usual water treatment using a combination of ammonia and chlorine. This ordinarily lasts only a few days.

If you are sensitive to chlorine, we recommend filling a jug of water and placing it in the fridge for at least 10 minutes, as this will dissipate the taste and smell of chlorine.

During the cleaning program, the water will contain more chlorine than usual, which can be harmful to fish and other aquatic organisms if not treated properly.

If you need to top-up or refill your fish tank or aquarium:

• treat the water with a suitable water conditioner, specific to chlorine

• consider passing the water through a filter or purifier

• let the water stand and aerate before use to help reduce chlorine levels.

We recommend speaking with your local pet shop or aquarium for advice on the best treatment options for your setup.

We encourage dialysis patients to discuss this water supply change with their dialysis provider.

We know how important it is to use water wisely, especially as we head into drier conditions.

Flushing is a necessary part of mains cleaning as it helps to move the chlorine through the network and ensures water quality across the whole system.

To minimise water use, we will:

• target flushing in the areas where it will have the greatest impact

• only flush for as long as necessary to achieve the desired water quality

• carry out all flushing in line with environmental management guidelines.

We are committed to doing this work responsibly while protecting our water resources.