Decades of discoloured water for Foxton Beach are hoped to be over from Monday but residents say they will believe it when they see it.
Horowhenua District Council have spent $270,000 on a new greensand filtration system, which has been added to the existing water treatment plant.
Water services manager Paul Gaydon said clearing the water at Foxton Beach was more difficult than in Foxton, which was fixed last year.
"It was trickier than fixing the town water supply, I just did that with chemicals, but this is a new add in to the existing plant," he said.
Mr Gaydon said the water was not dangerous but was discoloured due to manganese in the groundwater.
"It just came out slightly coloured and some houses were worse than others depending on where they were along the piping but the moment I saw it, I knew it had to be sorted out."
"It doesn't harm one at all drinking it. But our instincts tell us that if it doesn't smell good or look good then it's not good."
All up the council has spent about $400,000 on fixing the water at Foxton and Foxton Beach.
But, Foxton Beach resident Gael Bassett said they had been told it would be fixed "soon" for years.
Ms Bassett moved to the area in 1999 and first complained about the water in 2001.
She said she does not use her tap water unless she has to.
"The smell is horrendous, even when you boil it you can still taste it. I have had clothes ruined because of it, but now I always run the bath water first to try and clear it."
She said running the taps to clear the water was a huge waste.
"I had to run four bath-fulls this morning to clear it and we're paying for water that we get through the taps - we pay water rates."
Ms Bassett said the manganese left a residue and was concerned it was damaging her appliances.
"I've had to replace my dishwasher and washing machine. I know things aren't made to last these days but I wonder if it's to do with the residue."
"It stains everything, it stains porcelain for instance and leaves residue. My argument is if you're bringing cold water into your hot water cylinder, what's that looking like inside. That residue must still be there."
She said come Monday she hoped the issue would be fixed, but would not hold her breath.
"Seeing is believing and then I possibly will die of fright so we'll wait and see.
In Marton, brown tap water has been an issue for years - also caused by the presence of manganese.
Rangitikei District Council chief executive Ross McNeil said as of last week a sophisticated monitoring and alarm system was keeping track of water quality and less chlorine was being added.
"The result is clearer water, less chlorine and greater control over water quality and consistency."
He said heavy rainfall could cause Manganese to enter the tap water, but it would not be permanent.
"While we're confident we've overcome Marton's ongoing brown water by better managing levels, we can't rule out brown water in the event of unnaturally high flows - which increases pressure on the old pipes and 'scrapes off' Manganese build up, or if we have a pipe blow-out."