Government response to TMV submitters

Friday April 18, 2014 Written by Government Published in Weekend
Workers put finishing touches to the Te Mato Vai monument in February. 14021915 Workers put finishing touches to the Te Mato Vai monument in February. 14021915

Significant changes have been made to the Te Mato Vai Master Plan as a result of formal and informal consultation over recent months.

The main ones were tabled in an executive summary presented to a meeting of stakeholders at the Crown Beach Resort last week.

The submitters’ concerns (generalised) have been responded to as follow:


Low yielding intakes should not be rehabilitated. TMV should concentrate on rehabilitating only those with sufficient yield.

The rehabilitation upgrading works that are required at the 12 intakes may be very minimal. These will depend entirely on the detailed design investigation and condition assessments of the existing intakes.

Construct water galleries like those at Avana instead of the proposed design.

There is a good understanding of what is to be expected from the rehabilitation of these water intakes. Structural and civil requirements are not expected to be great but will probably be focused more on filtration improvement at the weirs.

Relocate water intakes at higher levels to achieve constant pressures. Re-design water intake weirs.

Relocating intakes to higher locations from existing sites will depend on factors such as:

·         Intakes are usually identified at points of intersections of two or more stream branches. Relocating intakes up higher may result in collecting water from only one stream. This will be looked at during detailed design.

·         Land acquisition issues if identifying a new location from the existing ones.

·         Catchment water quality will have to be reassessed to ensure appropriate treatment.

Cut in new roads to new location of new intakes.

Agree that although rehabilitating access road will be essential for intake maintenance, it will provide wider public access to water intakes and hence possible contamination. Therefore consideration on the level of improvement for these access roads will be another issue of discussion at detailed design. Security fences for the intakes will need to be considered.

Why are alternative water sources not being considered (Dr Chan’s underground aquifer galleries)? Restore Akaoa Reservoir to cope with tourist accommodation demand.

Alternative water sources will also be considered during the detailed design, but will need to be the most economically reliable option. Ensuring sufficient amount of water is captured from the aquifer; some drilling is essential and also should be drilled down to mean seal level. There will be a costing impact on this as well.


Some people argue that they do not want the proposed treatment plans to be constructed, yet still insist on having good quality water.

The proper locations of these treatment plants will depend on:

·         National Water Standard for the level of service (flow rate, pressure, velocity) required at household. AECOM has already given their recommendation in the draft master plan and need to formalise in terms of Cabinet approval of standards.

·         The allowable head from the intakes in order to ensure proper sedimentation and treatment rate of processes.

Where will these treatment plants be located and will Government compensate the landowners?

The treatment plans will require new land to be properly acquired by the Government and be included in the specific lines of consultations. Detailed design will assess the relevant appropriate type of treatment plants and the amount of land required will depend on the type of treatment plant adopted.

Will these treatment plants use a lot of electricity and what are the operational and maintenance costs?

The energy consumption depends on the type of treatment plant adopted; those recommend3ed in the draft master plan require a lot of electricity to operate. Other available technologies do not need electricity to operate and are very efficient.

We do not want chemicals in the water. The pharmacists are advocating support the use of fluoride because of the benefits to children.

This is an anticipated reaction every time chemicals are introduced to disinfect water. The concern centres around the acid which is present in both chlorine and fluoride and potential impact on health. It should be noted that fizzy soft drinks contain more acid that the proposed level or chlorine needed for water disinfection or fluoride.

Others do not mind the use of chlorine to disinfect water as long as the smell and taste is well controlled. Fluoride and chlorine will cause harm to the people.

WHO guidelines allow the existence of 250 ppm of chlorine in the water which is still not a health risk and will give potential small. If chlorine is added to disinfect water it will be in the order of 0.5 ppm and 1.0 ppm. This will ensure around 0.2-0.3 ppm at the household level which is still sufficient to disinfect and kill bacteria and e-coli.

UV treatment was also supported by most people, but there was strong advocacy for individual UV treatment at the household.

UV treatment only is not sufficient to disinfect public water supplies from a central location as water can be contaminated down the distribution line as well. The estimated cost to purchase and install an individual household UV facility to meet WHO standards is in the order of $3000. Purchasing 3000 UV units to cover each household can be estimated at $9 million, as opposed to the estimated cost of both treatment plants including centralised disinfection facilities.


Three days of water storage is insufficient.

The key to sustainable water supply is not to construct more and larger capacity storage tanks, but to control demand at the household and also fixing waster and leakage.

More storage needed as advocated by a strong few.

As above, building up larger capacity storage tanks and not resolving the demand side is a non-productive approach to the problem. Sufficient sizes should be considered carefully during the detailed design phase.

How long can the proposed storage sustain the country in a drought? And will it be enough?

Three days, as in the draft master plan but this will be dependent on final demand. Huge capacity tanks also require more land. About 250,000 litres at each intake site may be just sufficient at this stage until demand is reduced, then more storage will be required.


Do we need to replace the trunk mains?

Some recently constructed trunk mains in the 1990s may not need to be replaced. During the detailed design phase all trunk mains should be pressure tested or another form of testing to decide whether they need to be replaced or not.


Recommendation – Government to plan construction of an inner road at the missing portion (1.5 km) at around Titikaveka (Kauere-Vaimaanga) to commence together with the inner pipeline construction.

Will they come through my property?

A decision has been made for the entire inner pipeline to be constructed alongside the inner and outer roads. However, there is a portion which requires proper negotiation around Titikaveka, behind the Sheraton Hotel. In discussion with Infrastructure Cook Islands, there will be a road constructed around that area in 201415. This is still regarded as a risk at this stage because the road plan may be too late.

Can’t we do the ring main only?

Some of the trunk mains are asbestos concrete, which are required to be replaced to eliminate all leakages.

Will consumers have the option of alternating between main supply and private storage?

This is up to the consumer as private storage has not been discouraged in the project. At this stage, encouraging use of the rainwater catchment will also assist the demand risk.

Why was their so little time for consultation?

PMU felt the project had been communicated through all different types of media. Even before PMU came on board, TMV consultation started way back in 2009.

Why hasn’t a large culvert been constructed around the whole island to allow for all utility services – this option would be more simple and efficient for all utility service providers?

This is an ideal option and should be discussed by the Infrastructure Committee. From a TMV perspective it will require a variation cost to Government to pay CCECC; TAU has already been in contact about the possibility of sharing trenching with their cables.

It has been suggested that water supplies be made available to consumers at high altitude.

This will be dictated by the required National Water Engineering Standards, currently being developed through IPECI and ICI.

There should be a separate supply for agriculture from potable water.

This suggestion will also be considered during the detailed design phase but it depends on water resource development priorities and also conducting a water balance equation considering the demand/source.

Are there any land issues?

Rehabilitating existing asses should not cause any major land issues; the pipeline should be constructed within a metre of the existing pipeline and still follow the existing road alignment.

Not all of the sub main pipelines parallel to the ring mains have been replaced – so the leakage may still be occurring even after the replacement of the ring mains by CCECC.

Quite a portion of the sub main pipeline has been replaced by ICI. PMU has been advised that ICI will replace the rest using their existing budget before the completion of ring main construction. The sub main around Tupapa and Matavera is included to be replaced.


We do not want meters installed at our home; when meters are installed that means water will be charged for.

This is very essential for the success of the Te Mato Vai project. Meters have to be installed in order to properly monitor usage and especially wastage by calculating water loss and encouraging customers to conserve water. A policy is now in place to charge water supply services to commercial customers and also excess usage by domestic customers.


Recommendation – remove this activity from the core list of Te Mato Vai project as it is now adopted by WATSAN under its Integrated Water Resource Management programme.

Why do we need a ground water study? We already know we have ground water.  There is a concern that groundwater studies have been done in the past and data is already available.

This has already been advertised by WATSAN and this activity is still under consideration from the list of projects needed to be conducted jointly with TMV. It is an essential project but only very important during the commissioning phase of TMV and once the demand is reduced; boreholes and pumps may not be needed.


Who will pay for the power of these pumps? There is concern at the on-going cost.

On-going cost can be included in the operation and maintenance cost of the whole water scheme. Local booster pump operational costs will be very immaterial compared to the whole operational and maintenance cost of the scheme. Pumps are also operated on pressure management consumption.


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