Some residents in the Wellington region are being warned they might notice a bit of an unpleasant smell today.
An urgent repair is needed for the sludge dryer at Seaview Wastewater Treatment plant.
Sludge is the term for the solids produced from the wastewater treatment process.The dryer works by usingheat to evaporate water and sterilise the sludge.
Wellington Water wastewater chief adviser Steve Hutchison said a screw that feeds the sludge into the dryer is broken and needs replacing.
The repair won't be too significant and should be completed within a day, he said.
"The sludge does have an unpleasant smell unfortunately ... so we're minimising the smell as much as we can", Hutchison said.
A perfume system has also been installed at the site to try and reduce the smell, which just the neighbours will probably notice, he said.
Wellington Water manages water assets for the Hutt, Porirua, Upper Hutt and Wellington City councils, South Wairarapa District Council, and Greater Wellington Regional Council.
The company posted on social media that people in and around Seaview or Silverstream could be affected by the smell.
"We know that wetter sludge can carry some unpleasant smells, and we appreciate your understanding as we work to get the dryer running as quickly as possible."
"Rest assured, the unpleasant odour doesn't carry a public health risk."