6  May 22 - Precautionary Boil Water Notice LIFTED

Residents on the Springfield Water Supply are advised they no longer need to boil their water.

However, for customers who have their own private water tank(s), it is recommended to continue to boil your water until the water in the tank has turned over. To do this you will need to know the size of your tank and have an understanding of how much water you use on average, to estimate how much extra time to boil your water.
Alternatively, you can add additional chlorine (unscented plain bleach) to your tank, or flush your tank through.

You can find more information here.

All customers with restricted water supply are required to clean and disinfect their tanks annually.
The water tanker and the shower block will remain over the weekend.

We acknowledge this has been a challenging time for the township. We will continue with the long-term programme of works to upgrade the township supply.

Since May 2021, the Springfield water supply has seen a series of ongoing issues due to a reduction in the water quality from the river, leading to an increase in precautionary boil water notices.

The Council is working on a series of options to address these issues. The nature of the water supply around Springfield means there is no single or quick solution, but the Council is committed to providing a safe, clean and reliable supply of drinking water to Springfield and to addressing these issues.

Background

The Springfield drinking water supply is drawn from the Kowai River. It is one of eight river-fed supplies in Selwyn.

The supply was upgraded in 2017 to include 1 micron (0.001mm) Cartridge Filtration followed by UV treatment, in addition to the previous chlorine treatment system. Treated water is then fed direct to the township or stored in two treated water reservoirs allowing for just under 400m3 of stored water for distribution when needed.

Unfortunately, the current treatment systems have provided inconsistent treatment during heavy rain events.

Since May 2021, local feedback and available monitoring data suggests that the source water quality has changed.

Investigations by the Council have identified landslips in the Kowai River valley as the likely cause of change in water quality and investigations are being carried out into what can be done to reduce this. It is also possible this may stabilise or revert back to the previous conditions over time.

What are we doing?

The Council is working on a number of projects to address these issues. These include:

  • Construction of additional reservoir storage which is underway
  • A membrane plant trial to provide additional filtration of the water
  • Search for alternative water sources
  • River works to return the Kowai River to its pre-flood channel in places
  • Building a pipeline from Sheffield to Springfield to allow water from Sheffield to supplement in the Springfield supply in conditions when the Springfield supply is compromised.

For more detail see our current projects information below

Latest updates - 6 May 

Update - 6 May

PRECAUTIONARY BOIL WATER NOTICE LIFTED

Residents on the Springfield Water Supply are advised they no longer need to boil their water.

However, for customers who have their own private water tank(s), it is recommended to continue to boil your water until the water in the tank has turned over. To do this you will need to know the size of your tank and have an understanding of how much water you use on average, to estimate how much extra time to boil your water.
Alternatively, you can add additional chlorine (unscented plain bleach) to your tank, or flush your tank through.

You can find more information here.

All customers with restricted water supply are required to clean and disinfect their tanks annually.
The water tanker and the shower block will remain over the weekend.

We acknowledge this has been a challenging time for the township. We will continue with the long-term programme of works to upgrade the township supply.

29 April

Work on the new pipeline from Sheffield has started with the container pump station being built off site ready to move onto site at Annat when the pipeline is installed.

We are starting to see improvements in the source water quality we believe because of the recent Kowai in- river works.

The water is not yet at a quality where we can lift the precautionary boil water notice, but the results are encouraging so far.

The river work has involved moving the river back to its pre-flood channel and away from an area of vegetation the river had started flowing through on one of its meanders. We’re grateful to Environment Canterbury for helping us get work started quickly. Environment Canterbury will also assist with phase 2 which will look to ensure the river stays within the desired channel.

As water quality improves over the next few weeks contractor staff will be onsite checking the pipes through the town, including pumping high pressure water through to ensure there are no blockages or ongoing issues in the network.

Work on the additional storage tanks is continuing and is on track to be completed in mid July, weather depending. Design of the membrane treatment plant is also continuing.

ional storage reservoir and tanks is continuing

Precautionary Boil Water Notice in place

  • A Precautionary Boil Water Notice is in place for the Springfield water supply
  • The potable water tanker located outside the Springfield Community Hall remains in place.
  • The shower block placed at the Springfield Community Hall remains available for use.
  • Smylies Accommodation remains available for residents to carry out their laundry.

Ongoing testing and monitoring shows that the UVT is still not yet at the point where the UVT treatment process can be guaranteed effective under Drinking Water Standards.

Current projects

Additional reservoir storage 
This should help to prevent the supply being interrupted during smaller rain events and improve resiliency. Additional storage will allow treated water to be supplied while the treatment plant shuts down and provide better chlorine dosing control.
Work includes:
* Construction of a new 500 m3 reservoir for treated water
* Construction of two new 30 m3 storage tanks for raw water (water before it goes through treatment)
* Further space has also been allowed for additional reservoirs/tanks
Planned completion in mid-2022.

Membrane trial
Trials of a membrane treatment system have been complete and design is under way for a proposed membrane treatment system to be put to the Council for approval.
Membrane treatment filtres smaller particles from the water than the current cartridge filter system. The capital works required could be in the order of $2–4 million.

Sheffield to Springfield Pipeline
The Council has agreed a project to build a pipeline and associated works to allow water to be pumped between Sheffield and Springfield to supplement the water supply when it is compromised. This will allow water from Sheffield to be mixed with Springfield water to bring it to a point where the treatment plant is able to effectively treat the water to meet the Drinking Water Standards. or if necessary to fully supply the township for short periods on an emergency basis.

FAQs

Why are we getting so many boil water notices?

Following the May 2021 floods there has been a change in the water quality in the Kowai River. Heavy rainfall from last May has caused a large amount of silt, sand and clay material from landslips to deposit into the river bed. This material is relatively unconfined, which means that any further moderate rainfall can easily cause this material to be lifted out from the river gravels and mix in with the river water causing an increase in turbidity and a decrease in UVT.

Why are they lasting for so long?

Previous Boil Water Notices were caused by heavy rain washing material from landslips into the river, which after a short time would be completely washed through the river and water quality conditions would return to normal. Now because of the large amount of material that has been deposited in the river bed itself, we are noticing a much slower return to normal river water quality. Council cannot yet determine how long it will take for the Kowai River water quality to return to pre May 2021 levels.

What is the Council doing about it?

The Council is continuing to look for alternate water sources as well as working to ensure the existing system is working more effectively until an alternative can be found.
This includes:

  • Construction of a new 500 m3 reservoir for treated water
  • Construction of two new 30 m3 storage tanks for raw water (water before it goes through treatment)
    Due for completion in mid 2022, the additional storage in combination with other measures will reduce the amount of time a boil water notice will need to be in place.
    Further space has also been allowed for additional reservoirs/tanks
  • Construction of a pipeline between Sheffield and Springfield to allow additional supply to supplement the water supply when it is compromised. The budget for this work is $1.2 million.
  • River works to redirect the flow of part of the Kowai River back to its original course pre last year’s floods, to help  improve the clarity of the water.
  • Membrane treatment - Trials of a membrane treatment system have been complete and design is under way for a proposed membrane treatment system to be put to the Council for approval. Membrane treatment filtres smaller particles from the water than the current cartridge filter system. The capital works required could be in the order of $2–4 million.

What work has been done to find another water source?

There have been a number of reports undertaken to identify alternative sources for the Springfield scheme. These include:

  • Shallow Bore Supply
    Various sites investigated have shown a combination of insufficient supply, inconsistent supply and poor water quality. This includes investigations of the historic railway supply, a site close to the railway supply and a historic bore on Queen Street, which all show insufficient supply and high risks of contamination that increase in heavy rain events.

    These investigations involving consultants and specialist contractors has indicated that it is extremely unlikely that a shallow bore would provide enough water for the town.
  • Deep Groundwater Supply
    A number of deep bores have been drilled, none of which found any indication of deep groundwater.
    Coupled with investigations involving consultants and specialist contractors, it is extremely unlikely that there is any deep groundwater near the town.
  • Connection to the Malvern Hills Dalethorpe water supply
    Connecting onto Dalethorpe water supply has been considered as the end of the scheme terminates less than 130 m from existing reservoir. There is limited availability of water in Dalethorpe already. Dalethorpe also suffers from water quality issues during large rain events.
  • Ongoing investigation for alternative supplies
    The Council continues to investigate other alternatives and we will let people know as soon as a suitable alternative is found.

Have you looked up river for landslips that could be causing this?

A helicopter fly over of the Kowai River catchment was undertaken on Monday, 28 February 2022, with the aim of investigating what may be causing the discolouration currently occurring within the Kowai River. Damage from May 2021 flood event is still clearly visible. One slip in particular has been identified as the likely cause of the current issues and the Council is investigating what options may be possible to mitigate this.