Questions and Answers
What restrictions are in place currently?
Current water restrictions are always shown on our Water Restrictions page.
We are asking Selwyn residents on Council water supplies to try to avoid watering lawns between 6am and 9am and 4pm and 9pm daily. These are times when households use the most water and demand is especially high at these times at the weekend. Watering your lawn for one hour in summer can use as much water as a whole households typically uses in a day. If everyone waters their lawns at the same time over summer this places huge demands on Council water supplies.
The recommended time to water your lawn is between 9pm and 6am as this is when the least evaporation occurs and water has the best opportunity to soak into the ground.
If you are considering watering your lawn during the day between 9am and 4pm we recommend you check the weather conditions first. Watering during the daytime is fine on cooler overcast or wet days. Watering during the middle of the day on hot or nor’west days is not a good idea as a significant amount of water will evaporate.
Will water restrictions be introduced over summer?
Groundwater levels in Selwyn are currently lower than normal, and the Council also has water take restrictions affecting a number of water supplies.
The Council is currently requesting that residents follow our advice about when to water lawns. If demand for water increases over summer then water restrictions may be introduced requiring households to avoid watering lawns at specific times so that we can provide consistent water pressure and also conserve groundwater and meet ECAN water consent requirements.
The Council has a graduated system of water restrictions starting with restrictions on when watering can occur during the day, with the highest level of restrictions being a total ban on lawn and garden watering.
Could more stringent water restrictions be introduced over summer?
El Nino conditions are forecast to affect Canterbury over spring and summer. The El Nino is predicted to be the strongest since 1997-98. This is likely to mean a dry spring and summer which will increase demand for water.
If demand for water increases over summer then more stringent water restrictions may be introduced. The Council has a graduated system of water restrictions starting with restrictions on when watering can occur during the day, with the highest level of restrictions being a total ban on lawn and garden watering.
Why should people change when they water their lawns?
Over summer the demand for water for water lawns and gardens peaks in the morning and evening period when many people water their lawns and gardens at the same time. The highest demand often occurs at the weekend or after public holidays.
The restrictions will help to smooth demand for water use more evenly throughout the day and across the week.
What about new sections where residents are trying to establish lawns?
While council understands that residents wish to water their lawns, especially on newly established sections, it is preferable for people to do this at times of lower demand and on alternate days as this has the least impact on other households.
Why doesn’t Council just put in more bores?
It is preferable to manage these issues by reducing the level of demand for water at peak periods through water restrictions, as it would be expensive to add additional bores which would be used less than 5% of the time.
Water use by Selwyn households is very high – the average household uses over 1,000 litres per day. Typical consumption for a New Zealand household is around 675 litres per day by comparison. Water is not an unlimited resource and we want to encourage Selwyn households to use water in a sustainable way.
Has the Council been adding more capacity for our water supplies?
The Council is part way through a programme to add capacity to water supply systems in high growth areas.
Since 2015, Rolleston, Prebbleton and Lincoln have all had new bores added to supply these areas. Another bore has been developed at West Melton which is expected to start operating by summer. A new deep well has been drilled at Edendale which replaces the existing well, as dropping groundwater levels indicated the bore would soon go dry.
In Doyleston, a second pipe was constructed in 2015 to connect the town’s reservoir to the pipeline supplying the town from Leeston and more tank storage has been provided for Doyleston’s supply. These are helping to provide Doyleston with more consistent water pressure. In Leeston an upgrade to the well and a new high capacity pump has also been completed which provide both Leeston and Doyleston township water supplies with more capacity.
What about farmers using irrigation – do water restrictions apply to them?
The Council manages Council water supplies and water restrictions apply to properties supplied from Council supplies. Most farms source their water from their own private bores and don’t use Council supplies.
Rural property owners must meet Environment Canterbury requirements and restrictions on water use for irrigation.
What’s your advice to residents about water use?
Residents are encouraged to conserve water by reducing the amount of watering they carry out, and to water at times when it’s most effective.
The best time to irrigate lawns is early morning, as water has the opportunity to soak into the ground and be retained there. When irrigation is carried out in the daytime during hot or Nor West weather a lot of water evaporates and is wasted.
If residents have the option of setting a timer on their watering system, a good option is to irrigate lawns during the early morning between midnight and 6am, when demand for water is lowest. If you do decide to water your lawn during the daytime we recommend choosing a cooler, overcast day for this to reduce evaporation.
For more information, please read our Water Conservation page