A $1.8 million upgrade of East Otago water supplies is proposed by the Waitaki District Council this financial year, but it wants to hear from the Waihemo Community Board before making any final decisions.
The upgrading, to meet new drinking water standards, will combine the stand-alone Palmerston, Dunback and Goodwood water supplies into one, utilising one treatment plant.
That will have to be paid for by consumers on the three schemes, which serve a total population of about 1400 people.
The cost would be met by depreciation and a loan repaid by rates.
The council faces upgrading 21 water supplies by 2016 to meet Government's deadline for new drinking water standards.
Oamaru's has already been done at a cost of $12 million.
Work is being done on the Lower Waitaki scheme, a pipeline is planned to link Weston-Enfield to the Oamaru treatment plant and this financial year Palmerston-Dunback-Goodwood, Otematata and Hampden-Moeraki are also on the timetable.
The Waihemo Community Board, at its meeting on Monday, will be asked to recommend to the council amalgamating Palmerston, Dunback and Goodwood supplies, taking water from the Shag River alluvial bore at Mill Rd into one treatment plant and building new pumps and pipelines to supply Dunback and Goodwood.
Apart from being one of the cheapest options - the others range from $1.5 million to $2.7 million - it will also guarantee future supplies, even in droughts, for Dunback and Goodwood.
Neither scheme can supply any more water despite growth in demand projected at 37% for Dunback and 12% for Goodwood.
The council acknowledged the recommended development would have "a significant impact on rates", recommending the cost be spread equally among all.
It projects Palmerston water rates would rise from $318 to $479, but Dunback's would fall from $585 to $479 and Goodwood's from $508 to $479.
An engineering report on the proposal said all three water supplies "must upgrade" to comply with current legislation.
Combining the three schemes and using one upgraded treatment plant at Palmerston was the best technical solution to meet the standards and future growth.
Upgraded treatment at the Palmerston plant would include filtration and ultraviolet irradiation.
Combining the supplies was "significantly cheaper" than individual treatment plants, estimated to cost a total of $2.4 million, which would still not address future growth in demand.
