The Waitaki District Council will have spent more than $21 million upgrading 21 water supplies by 2014, but the largest and most expensive project has already been completed.
Assets group manager Neil Jorgensen said the council was having to spend the money to meet the drinking water standards set by the Government.
The first project tackled was the Oamaru water supply, with $12 million spent including a new treatment plant commissioned in 2007. Part of the upgrading included boosting the amount of water available which could then be used by neighbouring communities.
By doing that, the cost of upgrading neighbouring supplies was reduced, compared with upgrading their present sources of supply.
Work has already started on a pipeline to take water from the Oamaru treatment plant to Weston and Enfield, with upgrading those two communities costing about $1.5 million. Work is to start soon on upgrading the Palmerston, Goodwood and Dunback schemes at a cost of about $1.1 million.
The three separate schemes will use the Palmerston supply and one water treatment plant.
The cost of upgrading is being met partly by a mixture of loans, capital contributions and depreciation (where equipment and infrastructure is being replaced), having to be paid by the consumers on the individual schemes.
That is expected to have a major impact on water rates paid by ratepayers from next financial year onwards, as each scheme is upgraded. None of the council's schemes qualified for the Government's drinking water subsidy scheme.
Queenstown Lakes District Council water manager Gerry Essenberg said while the Public Health South report provided water quality results, the council's main concern was the ongoing issue of algae in Lake Wanaka.
"We are reviewing all these numbers and because we have not decided what we are going to do, it would be silly to guess what it would cost." he said.
"We're still working on that. We complete our long-term plan every three years, and that's due to be completed next year, so until that's in place we won't have a list of what we're doing."
Waitaki water upgrades
Upgrades already carried out in the Waitaki district and due to take place in the next few years (some costs are estimates at this stage).
2006-07: Oamaru water supply, cost $12 million.
2009-10: Lower Waitaki water supply, $495,000.
2010-11: Palmerston-Goodwood-Dunback, $1.1 million; Weston-Enfield, $1.5 million.
2011-12: hampden-moeraki, $611,000; Otematata, $630,000; Herbert-Waianakarua, $611,000; Kakanui, $611,000; Kurow, $380,000; Omarama, $611,000.
2012-13: Duntroon, $283,000; Lake Ohau, $283,000; Tokarahi, $630,000.
2013-14: Awamoko, $291,000; Kauru Hill, $406,000; Otekaieke, $291,000; Stoneburn, $406,000; Windsor, $406,000.
