Rain slows sewerage upgrade job

19:31, Apr 23 2014
timaru sewerage ponds
TOO MUCH WATER: Progress on Timaru's new oxidation ponds has been held up by wet weather.

Rain has delayed work on Timaru's multimillion-dollar wastewater treatment plant upgrade.

To the north side of Aorangi Rd, 30 hectares of land are being sculpted into primary oxidation ponds and 8ha into maturation ponds.

Work began on the project last April, but Timaru District Council's district services manager, Ashley Harper, said rain had all but stopped work for the past four weeks on one of the new oxidation ponds.

"The earthworks contractors will resume in spring. They had hoped to finish work on that pond by now. It's simply been too wet for them to work recently, and we accept that."

Harper said the other oxidation pond had already filled with irrigation water.

He expected irrigation water to be pumped into the maturation pond during the next few days.


"It's been slower progress than we hoped, but we don't anticipate the recent delays to affect the total cost of the project," Harper said.

The oxidation and maturation ponds are a key component of the $17 million upgrade of Timaru's wastewater system.

"But it's a major project, with many different aspects. Earthworks only make up about 40 per cent of the costs. You also have the creation of the wetlands, and the work involved installing the pipelines, pumping and generation," Harper said.

According to the National Institute of Water and Atmospheric Research (Niwa), Timaru has recorded 67mm of rain since April 1 - the monthly mean is 42mm.

Harper said the council was lucky some parts of the project, such as the 10-hectare wetland conversion at Aorangi Rd, were completed before the heavy rain.

"All things going to plan, we hope the project will be fully commissioned by December."

The Timaru Herald