Go back to the previous page

What are our options?

Option 1

Option 1: Upgrade existing scheme with end point treatment at each household

This option involves the installation of a raw water tank (where necessary), end-point treatment units in homes and the installation of backflow protection on the existing scheme. This brings the scheme into Taumata Arowai compliance via Mixed-Use Rural Acceptable Solution (MUR-AS).

Council would look after the treatment units and replace parts like filter cartridges and UV lamps when needed.

The main concern with this option is that drinking water would still rely on the old network that will need to be fixed and/or replaced in the future. The cost of renewing the network is not included here.

Estimated Costs

Capital

$ 1.4 million (+ GST)
Operational approx. $ 167,720 / annum


Targeted Water Rate Area Water Rate per annum Group Water Rate
Funding Model A $ 3,361.55/annum
($ 1,109.55▲) 		$ 109.09/hectare ($ 33.79▲) N/A
Funding Model B N/A N/A $ 866.34 per annum
($ 50.69▲)


  • Advantages

    Helps the scheme meet drinking water rules, once backflow risks are fixed.



  • Disadvantages

    Council would need to manage at least 34 treatment units.

    Drinking water would still rely on an old network that will need more work.

  • Risks

    There is also a risk that heavy rain could affect treatment performance.

Option 2

Option 2: Build a new drinking water only scheme with end point treatment at each household

This option would build a new, smaller network for drinking water only.

Treatment equipment would involve the installation of a raw water tank (where necessary) and end-point treatment.

This brings the scheme into Taumata Arowai compliance via the Small to Medium Networks Acceptable Solution (SMN-AS)

Council would look after the new drinking water network, treatment units and replace parts like filters and UV lamps when needed.

The old network could be used for stockwater only and managed by a landowner group.

This would give Council more control over drinking water, but it would cost much more to build.

Estimated Costs

Capital

$ 6.9 million
Operational $ 95,000 / annum


Targeted Water Rate Area Water Rate per annum Group Water Rate
Funding Model A $ 32,895.53/annum
($ 30,643.53▲) 		$ Nil N/A
Funding Model B N/A N/A $ 901.42 per annum
($ 85.77▲)


  • Advantages

    Creates a new drinking water network that is easier to control and protect.

    The old network could still be used for stockwater and operated by a landowner group.

  • Disadvantages

    This is the most expensive option to build. Council would still need to manage at least 34 treatment units.

  • Risks

    Treatment units may still be affected when raw water quality is poor after heavy rain.

Option 3 (Preferred option)

Option 3: Households switch to rainwater tanks with end point treatment supported by council — Council’s preferred option

This option would use roof-collected rainwater for household drinking water. Each home would have a 25,000 litre rainwater tank and treatment equipment to make the water safe to drink.

Homes would be disconnected from the current Montalto scheme for drinking water. The scheme could then become stockwater only.

The Montalto scheme would no longer be a public drinking water supply. Council could transfer the water take consent to a local Montalto group for stockwater use.

Council would still look after the treatment units and help manage water if tanks run low, like tankering in water in a drought. This would need to be defined in more detail and discussed with the community.

Council prefers this option because it has a lower set-up cost than most other options and reduces reliance on the old network.

The drinking water supply could only be formally closed after the required legal process, including a referendum. Council has been trialling end-point treatment units at three households connected to the current supply. Those property owners will be able to share feedback on how the trial has worked.

Existing budget from Council’s Annual Plan 2026/27 could help pay for rainwater storage tanks and treatment units at each house.

Estimated Costs

Capital

$ 500,000
Operational $ 50,000 / per annum


Targeted Water Rate Area Water Rate per annum Group Water Rate
Funding Model A $ 7265.22/annum
($ 5013.22▲) 		$ Nil N/A
Funding Model B N/A N/A $ 832.89 per annum
($ 17.24▲)


  • Advantages

    Lower set-up cost than most other options, and reduces reliance on the old network.

    The stockwater system could be managed by a landowner group.

    This is Council’s preferred option.

  • Disadvantages

    Some landowners may not support rainwater collection and tanks.

    Council would still manage treatment units and help with tankered water if tanks run low.

  • Risks

    Closing the drinking water supply would need a legal process, including a referendum.

Option 4

Option 4: Each property chooses its own household water supply, not connected to the existing scheme

Under this option, each property would arrange and pay for its own drinking water supply, and would be required to disconnect their dwellings or other buildings from the scheme. Council would not manage treatment units.

The current drinking water supply would need to be formally closed through the legal process, including a referendum.

The old network could become stockwater only and be managed by a landowner group.

Estimated Council cost: about $30,000 plus GST. This amount being the costs associated with completion of a water scheme closure process. This excludes any costs that individual property owners will incur directly in the establishment of a suitable potable supply for their property.

Estimated yearly Council running cost: $0, because Council would no longer run the Montalto drinking water supply.

The main risk is that water quality could be different from property to property.

Estimated Costs for Council

Capital

$ 30,000 (to close the scheme)
Operational $ 0


Targeted Water Rate Area Water Rate per annum Group Water Rate
Funding Model A N/A N/A N/A
Funding Model B N/A N/A N/A


  • Advantages

    This has the lowest cost to Council, as each property could choose the water supply that works best for them.

    Council would no longer manage the water scheme or manage household treatment units.

  • Disadvantages

    Water quality could be different from property to property.Each property would need to pay for its own potable water supply.

  • Risks

    Closing the drinking water supply would need a legal process, including a referendum.

Options cost summary

Option Funding Model A Funding Model B Summary
Option 1: Upgrade existing scheme with end point treatment at each household & gradually renew existing network Set-up cost: about $1.4 million plus GST. $3,361.55/annum per household connection (+$1,109.55) $109.09/hectare (+$33.79) Ave 150Ha property: $19,773.80 (+$6,527.08) per annum About $866.34 a year for each Montalto group water ratepayer. Increase to the group scheme by $50.69 per user. Lower set up cost than Option 2, but higher yearly running costs.

Option 2: Build a new drinking water only scheme with end point treatment at each household.

Set-up cost: about $6.9 million plus GST.

$32,895.53/annum per household connection (+$30,643.53) $Nil/hectare (-$75.43) Ave 150Ha property: $32,895.53 (+19,648.81) per annum About $901.42 a year for each Montalto group water ratepayer. Increase to the group scheme by $85.77 per user. Most expensive option to build.

Option 3: Households switch to rainwater tanks with end point treatment supported by council — (Council’s preferred option)

Set-up cost: about $500,000 plus GST.

$7,265.22/annum (+$5,013.22) $Nil/hectare (-$75.43) Ave 150Ha property: $7,265.22 (-$5,981.50) per annum About $832.89 a year for each Montalto group water ratepayer. Increase to the group scheme by $17.24 per user. Council’s preferred option funded through Model A. Lower set-up cost and less reliance on the old network.

Option 4: Each property chooses its own household water supply, not connected to the existing scheme

Set-up cost: about $30,000 plus GST.

Not funded through the Montalto scheme. Each property would pay its own costs. Not funded through the wider water group. Lowest cost to Council, but each property would need to arrange and pay for its own drinking water supply.


Go back to the previous page