The septic tank has for many decades been a New Zealand stand-by. In the absence of reticulated sewerage schemes, tanks are a means of dealing with waste. As time passes they have become more sophisticated and, with proper maintenance and in proper places, they can perform satisfactorily.
However, as expectations rise, as the focus goes more on environmental and health issues, as some communities expand and as tanks fail, the pressure rises for alternatives.
The latest communities under the pump are Tokoiti, near Milton, and another South Otago hamlet, Benhar. Homeowners in each face one-off costs of up to $20,000, or $1700 annually, on top of present rates.
Not surprisingly, such figures - plus ongoing running costs and maintenance - cause anguish, even anger. How can a single superannuitant living alone on a total of $17,676 a year (after tax) or a married couple on $27,194 cope?
For both communities the issues have been around for a long time, and with every passing year the needs become more urgent. In Benhar's case, with its clay soils and poor absorption, evidence of the waste is there to see on the surface in places.
The Otago Regional Council, with its responsibilities for environmental matters and water and soil quality, has been applying some pressure but has, so far at least, been patient, not insisting on using its wide powers under the Resource Management Act.
The regional council has been involved with Benhar since 2005, when staff found unsafe levels of bacteria in effluent, while the Clutha District Council has had concerns since 2001.
The ideal solution in most cases is a full reticulation and treatment system. But given the costs, other answers, at least in the short term, can be worth exploring.
Sometimes, it is feasible to renew "on-site" treatment, although there is the danger of spending a considerable sum only to find the community requires full reticulation later, at an additional heavy cost.
Sewage treatment, whether it be for Auckland, Dunedin or Wanaka, is always one of the biggest costs for local councils and therefore ratepayers. The problems, though, are compounded in tiny communities which lack economies of scale.
Thus, the residents of the Tokoitis and Benhars are up against it. How fortunate are those settlements near Dunedin where the city council has agreed to use the resources of the wider city.
For instance, the costs for Allanton per household are about $4000 - 20% of the full expense.
Dunedin has other communities without reticulated sewerage, including Outram, Waitati, Purakaunui, Aramoana and Harwood.
Clydevale, Papatowai, Tahakopa, Taieri Mouth and Toko Mouth in Clutha also lack reticulated systems, as do Glenorchy and Kingston in Queenstown Lakes. In Kingston's case, problems are exacerbated because the shallow lying ground water into which septic tank outflow runs is also the drinking water source.
It was 20 years ago that Moeraki's scheme was completed, costing each household about $11,000, a huge amount at the time. Hampden is now in line as debate and investigation continues in what is among the biggest decisions local councils make.
In Central Otago, the wastes from Clyde make their way out of sight through porous ground, but that does not deal with the problem. And Patearoa, in the Maniototo, is also on the list of towns without reticulated sewerage.
For each community and council, the processes are made especially difficult because of the magnitude of the costs. There are, nevertheless, bright spots looking ahead.
Technology, whether it be for septic tanks themselves or in state-of-the-art plant such as that used by Fonterra at Stirling, is providing improved solutions, hopefully at lesser cost eventually.
In the meantime, communities can wrestle with ideas and schemes, and look to ways of lowering prohibitive expenses.
Already, Chilean "Biofiltro" systems are being proposed for upgrades at Kaka Point, Lawrence, Owaka, Stirling and Tapanui, with the costs lower than previously outlined.
As communities plead for more time, the various authorities have to continue to show patience while, at the same time, they must have specific timetables on a way forward. Expect a good deal more anguish and upset.
