Plans for the stage two upgrade of Dunedin's Tahuna treatment plant have been rejigged to ease the cost over the next few years.
However, Dunedin City councillors at yesterday's annual plan hearing decided not to change the overall timeline of the project - meaning the upgrade would still be completed by September 2011, as expected, and at the same overall cost of $73.8 million.
The council needed to complete the project by then to meet Otago Regional Council coastal discharge resource consent requirements.
The rejigged spending meant the cost in 2009-10 would drop by $5.9 million, from $11.3 million to $5.4 million, but rise in 2011-12 from $18.1 million to $21 million, and in 2012-13 from $22.6 million to $25.8 million, a report by council city environment general manager Tony Avery said.
The budget shuffle was one of three options considered.
Options two and three involved delaying construction with extra overall costs of $3 million or $9.3 million respectively, it said.
Council water and waste services manager John Mackie told yesterday's meeting there was strong community support to "get on with the project".
The Tahuna upgrade had been the subject of more public submissions, many of them "vigorous", than any other in his four years in the role.
"They support the project and are keen for it to be completed."
Cr Noone said the report highlighted risks, including trying to "re-litigate" consent requirements the city council needed to meet in 2011.
The council had achieved much in upgrading wastewater services over 20 years, including completion of the city's 1.1km outfall pipe.
Delays would cost money and damage perception of the council's efforts, he said.
Continuing with the updated "status quo" was the "most sensible" approach, he said.
Cr John Bezett agreed the cost of delays would be "totally prohibitive".