Filtering out a solution to Alexandra's water woes is proving a long and expensive exercise for the Central Otago District Council, which has spent about $240,000 during the past four years.
And there is more to come.
A report updating the Vincent Community Board on investigations into improving the quality of Alexandra's drinking water was discussed for more than an hour at Monday's board meeting.
Board member Tony Lepper was horrified to learn a further $420,000 might be spent on more investigation and work.
"I'd really choke to be spending that much," he said.
The $420,000 estimate included a $25,000 feasibility study into developing the existing borefield, $70,000 to further investigate the site and confirm its feasibility, $310,000 for developing a new wellfield and $15,000 on an assessment for protozoal compliance.
Instead, the board agreed to spend $15,000 looking into a water source which would utilise Clutha River water and groundwater, near and upstream the present borefield.
It also decided to further investigate the present site, with the total budget $105,000 for that.
As well, it planned to ask two companies, which claim to have systems which reduce the effects of hard water and limescale, if they would carry out trials of their product in parts of the town, free of charge.
The $240,000 spent by the CODC during the past four years has covered investigating water supply and quality problems and also identifying alternative sources or steps to improve supply.
The town's domestic water supply is sourced from six bores on the true left bank of the Clutha River, near Eclipse St, and the supply has had problems with hardness, scaling and occasional taste and odour issues.
It has an "E" grading.
Mr Lepper said it had taken four years of studies to get to this stage.
"The public is becoming increasingly dissatisfied with the slowness of the process," board member Martin McPherson said.
"It's the hardness of the water that is the main concern.
No-one in this town has got sick drinking this water."
Water quality has often been highlighted in the CODC's annual satisfaction survey as the number one concern of most residents.
Council development engineer Peter Morton said if there was a simple solution to Alexandra's water problems, it would have been sorted out years ago.
The board needed to invest in the best long-term solution to the water problems.
In response to questions from several board members, he said there was regular monitoring to see if water quality was affected by any potential leachates from the old tip site near the borefield.
