What is wrong with Norsewood's water?
Norsewood’s water treatment plant is to undergo an upgrade, but residents aren’t convinced it will fix problems with the town’s water supply.
Several homeowners in the town filled the War Memorial Hall for a public meeting with Tararua District Council (TDC) to discuss the upcoming upgrade of the water treatment plant.
The general consensus in the room was that the underground pipes supplying water to properties also needed upgrading.
Council Three Waters manager Roger Earp outlined some of the background to the water supply in the town, explaining that a bore was established in 1978 as a back-up and supplementary supply and at the time there were 74 connected properties with rainwater tanks.
By 2018 there were 85 connections.
Roger told the residents the bores delivered water through a reticulation network - about 4.5km long - but there were different pipes with varying diameters.
A new bore was drilled in 1997.
The water treatment plant was upgraded in 2011 to include plant housing and water softening units, with bacterial treatment through chlorination.
Project manager Eugene Priest said the upgrade would achieve free available chlorine levels within the supply and provide a protozoa barrier, or UV filtration, in the system.
Work on prefabrication for the upgrade was expected to start this month, with installation completed by June.
“What the upgraded plant will include is a basic filtration for the removal of iron and manganese, ammonia and some tannins within the current supply.”
There would also be a new standby pump, new water supply tank and updating of SCADA and telemetry controls so water can be monitored more effectively.
Regarding the water’s brown colour, Eugene said that until a few years ago the Norsewood bore was “what we call a secure bore” - not requiring chlorination or disinfection - but had since lost that status.
“[The council] had to then disinfect it and we do that through chlorination.”
He says the colour was due to a basic chlorine reaction with the iron and manganese and the council was trying to chlorinate as little as was allowable by the drinking water quality assurance rules to keep discolouration to a minimum.
The solution in the upgrade was to install prefiltration in a filtration medium that removes the metals, as well as ammonia and tannins to a level so chlorine would not bond to it.
But residents remained sceptical, with one holding up a bottle of discoloured water saying it was sediment, not discolouration.
She asked if the council would be cleaning residents’ tanks, and was told the council would only clean those they were responsible for.
“We pay our water rates and you’re giving us that,” the resident said, adding that she was bathing her children and washing her clothes in the water, and drinking it. She said the situation was “unacceptable”.
Another resident at the meeting told council representatives he was constantly buying water to drink.
“When are we going to get clean water here?”
Many brought up an issue with the pipes, firstly that the galvanised pipes were all rusted, which they felt meant that clean water going through those pipes would still end up dirty.
They were told the network would be flushed during the plant upgrade.
Another resident said the message from residents was that “the pipes are stuffed” and needed to be upgraded.
“If you’re going to start flushing, you’re going to rip them from the inside out and create more leaks.”
Other residents brought up issues with trying to find water pipes on properties and were told that information should be on LIM (Land Information Memorandum) reports as the council was only responsible for connections from the street to the toby.
However, Mayor Tracey Collis noted there was a challenge in the fact that as an amalgamated council, TDC had a “mishmash of records”, with Dannevirke’s records differing from Woodville’s, and some pipes in the network were buried “metres and metres” down.
Leanne Warr has been editor of the Bush Telegraph since May 2023 and a journalist since 1996. She rejoined NZME in June 2021.