Securing our Future Water Supplies

Securing Our Future Water Supplies How do we secure drinking water in the future for Timaru and Temuka communities?

The Issue

We can’t live without water! Making sure our communities have sufficient and safe water is one of TDC’s critical roles. Currently, all communities supplied by Council receive adequate and good quality water.

For Temuka and Timaru, however, there are quantity and quality issues that need addressing within the next ten years to ensure we can secure supply to these communities in the future.

Timaru water is currently supplied from two sources – the Pareora and Opihi Rivers. Water is piped from these sources to a reservoir in Claremont where it is treated. The Pareora water supply pipeline, which is a key supply to Timaru, has sections that are old and need replacing. Deferring its replacement may lead to higher water loss due to leaks or interruptions of supply.

The availability of water from the Pareora River water source is also an issue, particularly if extreme dry weather or rain events occur more often. Under its consent conditions, the Council must maintain a minimum flow of water in the river downstream of where it takes water. When the river is very low, as during the last few months, how much water Council can take reduces further. When it does rain, it can take some time for the water to clear sufficiently to enable it to be used for supply.

In Temuka, water is currently supplied from four shallow wells at Orari where it is treated and stored in a small reservoir before being piped to Temuka. Two previously used water sources, a spring and another bore are currently not used.

This is due to the poor state of infrastructure, contamination risks and poor water quality. Investigations are planned to determine the best option for securing Temuka’s water supply in the future.

Physical works planned for the Temuka water supply include replacing parts of the main pipeline from Orari to Temuka to reduce water losses. It is also planned to construct additional reservoir capacity.

This isn’t all that’s planned for water supplies. You can read more about other development projects in Activity Statements and Infrastructure Strategy.

The Options

Doing nothing is not an option for this issue. Water is a critical resource for the district’s communities and Council has a legal obligation to supply it.

Timaru

1) Renew sections of the Pareora River water pipeline and maintain our current approach to taking water

Sections of the Pareora pipeline would be progressively replaced to maintain the use of this water source. This would reduce water losses but not address the issues relating to water availability from this source. A further stage would likely be upgrading treatment facilities to enable water that is unsuitable for use (e.g. following rain) to be treated and used for water supply. The costs of this depend on the level of treatment upgrade proposed and the location and type of storage.

2) Investigate other drinking water source options and use an alternative to the Pareora source

A new source would be investigated as another major source for Timaru’s water. Possibilities include a standalone bore or sourcing water from existing or proposed irrigation schemes. The cost and impact on rates of these options would vary depending on what is chosen and are unable to be estimated at this point.

Temuka

1) Investigate an additional drinking water source

The existing drinking water sources would be retained and a new water source investigated as an additional source for Temuka’s water. The most likely option is a further bore possibly located near the existing treatment plant. This would cost around $0.3M.

2) Maintain the current sources and upgrade the spring to ensure it is usable for supplying Temuka

The existing water sources would be retained. The pipeline from the spring to the treatment plant would be upgraded and improvements made at the spring to minimise risk of contamination. This would likely cost around $0.8M, and would result in a small increase in debt and rates.

Preferred option

Option 1 is the preferred option for both Timaru and Temuka supplies.Funding has been included in the budget for both projects. For Timaru, the total pipeline renewal will cost around $20M. It would be funded through depreciation reserves and loans to be repaid over time through the urban supplies water rate. $17M will be loan funded. The first stage is planned to commence in 2017/18. This will have an estimated impact on the urban water
supplies rate of an additional $60 - $80 per year by 2024.

For Temuka, a budget of $0.3M has been allocated for this option. It would be funded through loans to be repaid over time through the urban supplies water rate. Other water source options will continue to be evaluated as to their future feasibility in addressing these issues.

Supporting Documents and Links

Water Safety Plans

Water Supply Activity Management Plan