Rangitikei District Council staff are confident Marton's water will be running clear in time for anniversary weekend when hundreds of visitors are in town for the Marton Country Music Festival.
Chief executive Ross McNeil said a process error at the plant earlier in the week resulted in discoloured water but it has remained safe to drink throughout.
"I'm confident that Marton water will be running clear by the weekend and we apologise to residents and business operators that have been affected," he said.
"If you have clothing or other material that has been stained by discoloured water, we ask that you contact us, as well as your insurer, as we may be able to help."
Staff have been flushing pipes around Marton and residents are being asked to run their taps, especially hot taps, to clear discoloured water.
McNeil said the issues had nothing to do with roadworks being undertaken on Broadway and Follett streets.
Properties with water meters wouldn't be disadvantaged, he said.
If a property's annual water charge is noticeably higher as a result of the flushing required, council would, on a case by case basis, look at reimbursement.
Marton draws its raw water from the B and C dams. The water is high in dissolved manganese.
With the right level of pre-chlorination most of the manganese can be removed through the treatment process, preventing any water discolouration.
On this occasion the pre-chlorination level was not high enough.
"I want to thank residents and business operators for their patience and reiterate that we realise how frustrating this issue is for you, and that we need to ensure the processes in place to provide clear drinking water are consistently followed," McNeil said.
Council can be contacted 24/7 on 0800 422 522 at 46 High St, Marton between 8am and 5pm, Monday to Friday.
Rangitikei mayor Andy Watson said anyone wanting to speak to him could also contact the council to make an appointment.