Find out more about where the water comes from for each area in Christchurch and Banks Peninsula.
The L'Aube Hill water treatment plant provides the water supply for Akaroa and Takamatua.
Water for the Akaroa water supply scheme is taken from four streams (Aylmers, Grehan, Balguerie and Takamatua) and two wells, one at Settlers Hill Road (41 metres deep) and one at Aylmers Valley (138 metres deep).
The treatment process includes coagulation, flocculation, membrane filtration, chlorination and pH correction. The new L'Aube Hill treatment plant replaces three treatment plants, which were at L'Aube Hill, Aylmers Valley and Takamatua.
New pipelines were constructed to connect Takamatua to the Akaroa system, to bring untreated water from Takamatua Stream to the treatment plant, and to pipe treated water to Takamatua. A new treated water reservoir was built on Old Coach Road at the highest point of the pipeline to provide storage for Takamatua.
There are two other main treated water reservoirs, one at the treatment plant site on L'Aube Hill and the other at the former treatment plant site at Aylmers Valley. There are also four smaller reservoirs. As well as storing treated water, these reservoirs supply pressure for the network and most properties in Akaroa are supplied by gravity from these reservoirs. In addition, there are four small pump stations to provide water for properties higher up the hill.
The Akaroa water supply scheme provides water to more than 1000 properties in Akaroa and approximately 130 properties in Takamatua.
This water is used to supply approximately 130 houses in Birdlings Flat.
Water for the Birdlings Flat water supply scheme is taken from a well on Jones Road, and is pumped to the treatment plant, which is between Baileys Road and Poranui Beach Road. Treated water is pumped to approximately 130 houses in Birdlings Flat. It is a restricted water supply, which means that each house has its own storage tank which can receive up to 1,000 litres of water per day.
Water was previously taken from a shallow well next to the treatment plant, but this became saline and did not meet one of the aesthetic guideline value in the Drinking Water Standards for New Zealand. This did not affect the safety of the water, but did affect the taste, so this well was taken out of service in 2013 and water brought in by tanker while a solution was found. Access to a 188 metre deep well on Jones Road was secured, and a pump station and pipeline was constructed in 2014 to convey water from the well to the treatment plant.
The water supply scheme was built in 1974, with untreated water from the well piped to properties Birdlings Flat. The treatment plant was built in 2010. Untreated water from the well is stored in above ground tanks, and then passes through a media filter before being disinfected with UV light. Treated water is pumped to properties in Birdlings Flat.
The Council has a consent from the regional council, Environment Canterbury, to take water from wells within the city, sunk down into the aquifers. There are 53 locations around the city where water is pumped into the pipe network. At each of these extraction sites there is at least one, and sometimes up to six, wells. These wells are typically 200mm and 300mm in diameter and are drilled down to depths ranging from 22–220 metres.
There are five layers of confined aquifers, with about 25 per cent of Christchurch’s water supply being sourced from the shallowest aquifer. A programme is underway in the northwest of the city to replace some shallow wells with deeper wells, and once this is complete only 15 per cent of the city's water will come from the shallowest aquifer. The water in these confined aquifers is under pressure, giving rise to artesian wells that in some locations flow freely at the surface.
In Christchurch, water is delivered into water mains by electrically driven pumps keeping the mains pressurised and charged. The pressure forces water out when you turn on a tap in your house.
Where reservoirs or large tanks are sited on hill areas, water pressure is maintained by continually supplying water to the level of the reservoir. In areas where there are no nearby hills to put tanks on, pumps are kept running to ensure a continuous water pressure 24 hours a day.
Although Christchurch appears flat, there is actually a significant difference in land elevation from the east to the west of the city. Up to five pressure zones are needed, depending on the height of residential development. In addition, there is also a small public water supply at Brooklands and Kainga.
The water supply network is controlled from a central control room. As the pressure in the system falls and rises around the district, pumps are switched on and off by a combination of automatic and manual controls.
A vast network of pipes cover all urban parts of the city. This underground infrastructure spans from Belfast in the north to the hill suburbs in the south, and from Templeton in the west to Taylors Mistake in the east. More than 1,700 kilometres of main pipes are laid - enough pipes to run from Christchurch to Whangarei. The total length of underground pipework, including submains, is 3,300 kilometres.
This network of pipes ensures that when a section of pipe has to be isolated for replacement or repairs, the number of households affected by stopped water supply is minimal. The main distribution pipes are made from fibrolite, PVC, polyethylene and cast iron. The pipes distribute all of the water and provide water for Council-maintained fire hydrants on the main pipes.
The Duvauchelle water supply scheme provides water to 187 residential and 12 commercial properties in Duvauchelle and Robinsons Bay.
Water is taken from Pipers Stream, and passes through settlement tanks before flowing by gravity to the treatment plant on Okains Bay Road.
The treatment plant was built in 2011-12, to replace the previous treatment plant to achieve compliance with the Drinking Water Standards for New Zealand. At the treatment plant, the water passes through a mixed media filter and a cartridge filter before being disinfected with UV light and chlorine. Treated water is stored in a reservoir, and from there it is piped to properties in Duvauchelle and Robinsons Bay.
During a storm, the amount of suspended material (turbidity) in the water increases due to runoff from the surrounding catchment. When the turbidity gets too high, water is returned to the stream rather than being piped to the treatment plant, as otherwise the treatment plant cannot treat very dirty water. This means that if it rains for several days, this can result in a water shortage. If this happens, water is brought in by tanker from another water supply scheme.
In November 2017, work began on a project to improve connections in the area. This will reduce the likelihood of contaminated water getting into the general supply. Connections are being upgraded with new smart meters that will allow us to more accurately monitor flows over summer and respond quickly if any issues arise.
One of the things people can do to safeguard their water supply is to install a 5000 litre water tank. This can also be a useful source of water in the event of a fire.
The Little River water supply scheme provides water to residential and commercial properties in Little River and Cooptown.
Water for the Little River water supply scheme is taken from Police Creek, and passes through a settlement tank before flowing by gravity to the treatment plant on Council Hill Road. At the treatment plant, the water passes through a sand filter before being disinfected with chlorine. Treated water is stored in a reservoir at the treatment plant site, and from there it is piped to properties in Little River.
It is a restricted water supply, which means that each house is required to have a storage tank which can receive up to 1,000 litres of water over 24 hours. It is recommended that you have a tank that has capacity for at least 48 hours of water.
During a storm, the amount of suspended material (turbidity) in the water in Police Creek increases due to runoff from the surrounding catchment, which makes it more difficult to treat.
The treatment plant is being upgraded to meet the Drinking Water Standards for New Zealand. A new 115-metre-deep well has been drilled on Council Hill Road to provide an additional source of water that will be unaffected by rainfall. Water will be taken from Police Creek and the well. Water from the well will be pumped to the treatment plant, where it will be softened and then disinfected by UV light. Water from Police Creek will pass through upgraded sand filters and then be disinfected by UV light. Treated water will be stored in a new, larger reservoir on the treatment plant site, which will reduce the likelihood of water shortages and has provided capacity for a limited number of new connections.
A new pipeline has been installed to extend the water supply to properties in Cooptown. Once the treatment plant upgrade is complete, water will be supplied to Cooptown and some rural properties as well as Little River.
The Council is responsible for pipes to the boundary of the properties, and for upgrading the water treatment plant.
Owners of each small settlement title in Little River and Cooptown can apply for connection. Rural title properties where the reticulation pipe passes within 100 meters of a dwelling can also apply for connection.
The Council will supply a restricted supply of one unit, or 1000 litres a day at a rate of 0.7 litres per minute.
Rural properties that do not meet the criteria will not be connected.
Commercial addresses that have a current allocation will retain that allocation, and any new commercial properties will need to apply.
The property owners pay for anything beyond the point of supply at the boundary as designated by the Council.
The property owner responsibilities are:
Each property owner who connects to the supply may need to lodge a Building Consent Application before installation of the tank and plumbing work associated with connecting the tank to the Christchurch City Council Restrictor and the dwelling. This work is required to be carried out by a licensed Craftsmen (Plumber). Building consent is generally not required to install a water storage tank under Schedule 1 of the Building Act 2004. Section 23 of Schedule 1 states that a building consent is not required for the following building work:
Building work in connection with a tank or pool and any structure in support of the tank or pool (except a swimming pool as defined in section 2 of the Fencing of Swimming Pools Act 1987), including any tank or pool that is part of any other building for which a building consent is required, that -
There will be no restriction to eligible landowners joining the Little River and Cooptown water scheme in future.
All applicants must meet the small settlement or connection to a rural property criteria, which is:
There will be no additional cost to join the scheme apart from any increase in the connection fee and targeted rate which are set each financial year. Costs include costs of extension of reticulation to enable connections.
The connection fee and any additional costs to provide supply are to be paid before the work starts.
Small settlement property owners connecting to the scheme will pay a targeted water rate. The rate for the 2016/2017 year is $180 per unit.
Residents treat their own wastewater though septic tanks. A wastewater scheme for Little River is not included in the Council's Long Term Plan 2015-25(external link), but may be included in a future Long Term Plan.
Water from the Pigeon Bay water supply scheme supplies water to 18 properties in Pigeon Bay.
Water for the Pigeon Bay water supply scheme is taken from a spring above Dick Stream, and passes through four settlement tanks before flowing by gravity to the treatment plant on Pigeon Bay Road.
At the treatment plant, the water passes through a disc filter and a cartridge filter before being disinfected with UV light. Treated water is stored in a reservoir on the hill above treatment plant site, and from there it is piped to 18 properties in Pigeon Bay.
It is a restricted water supply, which means that each house has its own storage tank which can receive up to 1,000 litres of water per day.
Treated water is stored in a reservoir and from there is piped to 164 properties, including the Wainui YMCA.
Water for the Wainui water supply scheme is taken from a 92 metre deep well on Wainui Valley Road. Water is pumped out of the well, disinfected with chlorine and also passes through a cartridge filter to remove any suspended material.
The Wainui water supply scheme is a restricted water supply, which means that each house has its own storage tank which can receive up to 1,000 litres of water per day.