Eltham's rotting buttermilk ditch has become a money pit that will cost hundreds of thousands of dollars to fix.
The South Taranaki District Council estimates the curdling milk stored at the town's wastewater treatment plant will drain between $350,000 and $400,000 from its coffers before it's rectified.
But ratepayers don't need to panic just yet because Fonterra has promised to foot the bill.
Council chief executive Craig Stevenson said for "practical purposes" council was funding the clean-up to start with, but there should be no "residual cost" to wastewater customers.
"The exception to this is the purchase of some capital equipment, such as aerators, which will obviously stay in council ownership - so these will be paid for by council," he said.
Last year, Fonterra dumped about three million litres of the milk byproduct, along with another 150,000 litres of milk tainted with drilling wastes, at the plant in an effort to deal with spring's record milk production.
But as the milk broke down those living near the plant were swamped by a sickening smell.
Stevenson said the cost so far included deodorisers, consultants, chemical dosing, both ferric chloride and caustic soda, equipment, pipework and electrical cabling for equipment.
"Plus three new aerators, a replacement pump and chemical dosing pump," he said.
A submersible aerator will suck gas from under the cover of the facility, known as an eader, into the water of its neighbouring oxidation pond, drawing 110 cubic metres of gas per hour.
The remaining waste will be transferred to the same oxidation pond where it will be treated.
The council can breathe at least one sigh of relief, as a recent gas composition test found methane levels were below the lower explosive limit. Council community services group manager Fiona Greenhill said as a result there was "no risk to residents".
- Taranaki Daily News