A review into upgrading Waipukurau and Waipawa's wastewater treatment plants is progressing with a draft terms of reference completed and the aim for physical works to begin in 2020.
Since the plants were upgraded between 2013 and 2015 with floating wetlands by WaterClean Technologies Ltd, neither had reached full consent compliance, the ongoing issue being exceedances of ammonia.
A wastewater specialist's review last year confirmed the plants would never meet their resource consent conditions, and it was estimated anywhere between $11.9 million and $36m might need to be spent to make them compliant.
Any cost associated with upgrading the plants would be additional to water investment projected in the Long Term Plan 2018-2028, currently under consultation.
An update on progress to finding a solution for the plants was presented to the council's environment and regulatory committee yesterday, which also covered off an enforcement order issued in July 2017 in regard to non-compliant discharges of E. coli at Waipawa.