Current Alerts and Notices (View all)

Road conditions(2) Swimming pools notice(1)

Dunedin City Council – Kaunihera-a-rohe o Otepoti
Green pattern.

Restricted water schemes

What is a restricted scheme?

Restricted schemes are used in some communities to make sure everyone has fair access to water at a reasonable cost. An agreed number of water units are delivered at a uniform rate through a restrictor, over a 24-hour period. Most households receive 1000 litres (1 unit) per day. Because restricted schemes deliver water at very low flow rates, households on the scheme need a tank to store water for use and allow for higher tap flows.

Am I on a restricted scheme?

Areas on restricted water schemes include West Taieri, East Taieri, Karitane, Merton, Seacliff, Waitati and Warrington.

How big a tank do I need?

A roof header tank is not big enough for a house supply. Your tank should be able to hold enough water for at least two days – for most households, the tank should be around 2m3–5m3. You may like to consider installing a larger tank if you think you need more water.

Because the pipes that supply restricted schemes are small, they usually don’t have enough capacity to accommodate the flows needed for fire-fighting. To accommodate fire-fighting needs, the New Zealand Fire Service recommends a tank of at least 45m3 and an adjacent hardstand area with suitable fire engine access.

When choosing a storage tank, you should consider how much water you need daily, weekly and in different seasons, as well as fire-fighting needs. The tank should hold enough water for your peak days, when your house is full or you need a lot of water. It’s also sensible to allow for potential shutdowns of the DCC water supply for maintenance. A 2m3 tank is the smallest that will provide for the household needs of an average family, not including extra water for gardening, etc.

What else do I need to know about my setup?

All household plumbing and outdoor taps should be supplied from your water tank. You shouldn’t have any connections between the DCC supply pipe and your water tank.

It’s important to protect public health by preventing the flow of water (and possible contaminants) back into the water supply. To prevent backflow, your tank must have an air gap between the service pipe inlet and the overflow pipe. The gap should be 25mm or twice the diameter of the service pipe (whichever is greater).

The DCC prevents backflow from household connections by maintaining a check valve in the boundary manifold (blue box) and the restrictor also minimises the risk of backflow. Modifying or removing these devices is an offence under our bylaw.

Many people install a float so they can easily check the water level in their tank.

Another useful tip is to have your main water outlet halfway up your tank and a reserve valve near the bottom. This means your tank can only drain halfway if you accidentally leave a tap turned on or a pipe bursts. After fixing the problem, you can turn on the valve to draw from the water reserve while waiting for the tank to refill. If you don’t have a float or halfway outlet, you can get these retrospectively fitted.

For any new water tanks or alterations to an existing tank, you may need building consent depending on the tank’s size and height above ground.

It’s important to keep the water in your tank turning over and to inspect, clean and maintain the tank regularly to prevent harmful bacteria or algae from growing. This can be a hazardous task, so it’s a good idea to have a professional look after your tank. You should also inspect your overflow pipe regularly to make sure it’s clear of vegetation or other debris.

Can I get more water?

You can apply to the DCC to have more water units delivered to your tank. Additional units are subject to availability.

If there’s a discrepancy between the water units you ask for and the restrictor size available, the water units delivered will be rounded up to the nearest available restrictor size and charged accordingly.

If you don’t have enough storage and run out of water, the DCC is not obliged to provide extra water. However, in some circumstances the DCC may bulk fill your tank, at your cost.

What happens if I subdivide my property?

When a property is subdivided, its water units may be re-allocated within the subdivided parcel of land as approved by the DCC. If a new connection is needed, the property owner must apply to the DCC.

Can I take my restrictor out?

You must not remove or modify your restrictor. The DCC inspects restrictors regularly and you may be prosecuted if the restrictor has been modified.

Only DCC staff and authorised contractors may remove or change restrictors. If you are having issues, please call us on 03 477 4000.

Still didn't find what you were looking for?