Palmerston South water pressure management

Depending on where you live and your household plumbing you may not notice any changes; or you may notice a small decrease in water pressure. The decrease in the highest pressure might mean it takes longer to fill the bath or the washing machine, but there should be little or no noticeable change to the lowest water pressure you receive.

Water pressure in the area usually ranges between the minimum service level of 15 metres head (about 150 kPa) under normal operation and 60 metres head (about 600 kPa).

It’s normal for water pressure to vary from home to home, even in the same street. This can happen because of:

• Location: Homes at the bottom of a hill or closer to water tanks often have higher pressure than those higher up or further away.
• Demand: Pressure can change depending on how much water is being used at the same time, both in your home and across the neighbourhood (e.g. in the morning and evening).
• Household plumbing: Some homeowners have installed a pressure reducing valve (PRV) or pressure limiting valve (PLV) to control pressure. These are typically installed on the property side of the water meter or before the water pipe enters your home. In older homes, there may not be one installed or it may need maintenance.

Australian Standards (AS/NZS 3500) require a PRV or PLV be installed if pressure is higher than 50 metres head (500 kPa), to help protect your household pipes and appliances.

The proposed change will reduce the highest pressures by about 5 to 10 metres head (~50 – 100kPa). When works are complete the high water pressure in most of the area will not be above 50 metres head (~500kPa).

Minimum pressure will reduce by about 5 metres head (~50kPa) or less. You will still receive above our guaranteed minimum network pressure of 15 metres head (~150kPa) under normal operation.

We expect many customers will see better minimum pressure despite the reduction in maximum pressure. This is due to the increased network control the changes introduce.

See our Customer Contract, page 16.

While we install the new pipes and adjust the pressure management devices we will temporarily change the direction of water flow in some parts of the network.

Changes in flow direction can sometimes cause a temporary change in water colour if sediment in the pipes is disturbed. If you run your taps for a couple of minutes it should clear.

For more information about water quality and colour see our water quality web page.

A pressure reducing valve (PRV) or pressure limiting valve (PLV) regulates the water pressure entering your household plumbing.

If you already have one of these valves installed the change may be less noticeable as the water pressure may already be reduced before it enters your household plumbing.

Your water using appliances will still work the same. They may take slightly longer to fill and you may need to adjust your taps to deliver water as quickly as you want.

For most customers we don't expect a lot of difference.

You may need to check your garden irrigation to ensure you’re getting the coverage you want and adjust as needed. See our Saving water in your garden web page for tips on saving water at home and at work.

How much businesses in the area are impacted will depend on the type of the business and its location.

For most businesses we expect the change in pressure to be small or to go unnoticed.

If you are concerned about your water pressure you can contact us on email at customerservice@powerwater.com.au or call us on 1800 245 092.

We have modelled the potential impact to the area and minimum fire fighting pressures are not expected to change significantly.

Private fire fighting systems are the ongoing responsibility of the property owner. If your property has a fire service, you should be aware of the change when next testing the system. You may need to have it assessed by a hydraulic consultant to make sure that the new pressure level won’t affect its operation.

If you are concerned about your fire service water pressure, we can provide modelling results for the estimated new minimum pressures. You will need to provide us with the firefighting flow you require, or we can assume a rate based on the type of development present.

Please contact us on email at customerservice@powerwater.com.au or call us on 1800 245 092.

The water mains in much of this area are about 40 years old and should have a lifespan of 60–70 years, so this work will help keep them in good condition.

Several water mains breaks have occurred in this part of the network. Reducing the water pressure and managing the amount it fluctuates is a proven method used by water providers around Australia and the world to get the best performance from existing pipes.

We are also installing several new sections of pipe to support the recently upgraded water pressure management devices in the network.

The main benefits of this water pressure management project is prolonging the life of our water network and your household plumbing.  In achieving this we will reduce:

• high water pressures to a more sustainable level
• the fluctuation in water pressure
• mains breaks
• supply interruptions.

We are focusing our pressure management program on areas with higher-than-average disruptions to water supply and higher than necessary pressure.

Much of the Palmerston region and the rural area already benefit from water pressure management and have lower water pressure than Bellamack, Driver, Moulden, Rosebery, and Woodroffe.

Water pressure is the force needed to move the water from our mains to your household.

If there is too much pressure the network pipes can become stressed, as well as household connections and equipment. With higher pressure any water leaks or pipe breaks will have a larger amount of water loss.

Metres head is the measurement used to determine water pressure. It refers to the height (head) water would rise vertically in a pipe e.g. 15 metres head of pressure would allow water to rise to a height of 15 metres.

A quick online search will show that water pressure management is standard practice with water utilities around Australia and the world. Reducing unnecessarily high-water pressure helps water infrastructure last longer and reduces the amount of water lost through leaks and breaks in water networks.

We will be monitoring water pressure before, during and after the changes to ensure the minimum water pressure we deliver does not fall below our guaranteed service level of 15 metres head (~150kPa).

If you are concerned about your water pressure you can contact us on email  at customerservice@powerwater.com.au or call us on 1800 245 092.