A brighter picture is being painted of the overall operating costs of Whanganui's replacement wastewater treatment plant than initially forecast.
Whanganui District Council chief executive Kym Fell said council staff have refined the operating costs of the Airport Rd plant and this, coupled with low interest rates and foreign exchange movement, has produced a "more favourable" cost than that forecast in the 2015-25 10-Year Plan.
The changes affect the operating costs of the plant and not the capital costs of building the new plant which remain that same at $41.5 million.
Mr Fell said the continuing review aims to reduce costs to residential and commercial properties, as well as to the trade waste industries.
"We've been doing a lot of analysis behind the scenes on our financial modelling to see how we can make the plant more affordable for our community," he said.