Palmy's main water pipe to be cleaned

Published on 10 August 2022

Green tile with white text that says water update.

One of the two main pipes that get water from the Turitea Dam to homes and businesses in Palmy is being cleaned to ensure our city’s water remains in pristine condition.

We’re planning for this to take place overnight on Wednesday 10 August, however, we require certain conditions so this date could change by a couple of days.

No cleaning agent is used during the process – instead a giant sponge is inserted into the pipe at the treatment plant and water pressure pushes it through the pipe until it gets to the river.

When we clean the pipes, we need to discharge a lot of extra water into the Manawatū River. We have a resource consent to do this, but we need the river to be in certain conditions. We will know with 24 hours’ notice and will let you know on our website and Facebook page.

The Council’s Three Waters Group Manager, Mike Monaghan, says water supply will continue as normal for most of the city, but a few homes in Turitea will be without water as the work takes place. Any homes affected will receive a letter from the Council.

One of the potential side effects of cleaning the pipes is that it can cause the water to discolour for a brief period, Monaghan says.

“This is normal. If you find your water isn’t clear the morning after the pipes have been cleaned, run your outside tap for 20 minutes. If the water hasn’t run clear, then please call us and we will get the pipes near your home flushed.”

Monaghan thanks residents for their cooperation.

 “Palmy’s drinking water is even cleaner than recommended in the National Drinking Water Standards, and we want this to stay the case. Regular maintenance like this ensures our residents continue to have the cleanest water possible.”

Why do we clean the pipes?

The pipes need to be cleaned regularly to flush out any build-up of manganese. The water is naturally slightly rich in the mineral as it comes from a dam. Almost all the manganese is removed during the treatment process, but minimal amounts can remain. The mineral is safe to drink but can cause water to discolour. Cleaning the pipes ensures this isn’t a problem.

How do you clean the pipes?

We start by shutting off certain valves (or gates) to the main pipe. This causes the water to be stuck behind these gates. We then insert a giant sponge into the pipe. Then we open those doors and the pressure of the water pushes the sponge through the pipe. As it moves through the pipe it cleans it. Near the river we remove the sponge, so it doesn’t end up in our precious awa. The water and any sediment are then flushed into the Manawatū River. Our resource consent conditions have very strict rules about when we can do this work to ensure the effects on our river are as minimal as possible. 

 

Why can’t you give us an exact date when the pipes are being cleaned?

When we clean the pipes, we need to discharge a lot of extra water into the Manawatū River. We have a resource consent to do this, but we need the river to be in certain conditions to ensure the environmental impacts are minimal. Mainly this is about the flow of the river, and how murky it is.  

We will know with 12 hours’ notice and will let you know on our website and Facebook page.

Why does the water go dirty?

Our dam has slightly higher levels of manganese. We remove almost all of it during the treatment process, but we can never get it all. Over time this can build up in the water pipes. We remove it so that you don’t have discoloured water often.

Why can’t I wash my clothes that night?

Try not to do loads of washing overnight on the night we clean the pipes. If the water does become discoloured it might stain your clothes – and we don’t want that to happen.

Will I get dirty water?

Sometimes when we clean the pipes it can cause the water to change colour briefly. We can never predict if this will happen.

My water is dirty, what do I do?

If you find your water is discoloured, please run a cold tap for 20 minutes. If it isn’t clear after that long, call us on 06 356 8199 and we will flush the pipes near your property.