Forced chlorination of the remaining 20% of Christchurch’s water supply will begin later this week.

On 9 May Government water regulator Taumata Arowai advised that it intends to decline Christchurch City Council’s first chlorine exemption applications.

A spokeswoman from Taumata Arowai earlier told Chris Lynch Media it was just a “draft plan” but that was not the case.

The lowest dose of chlorine, that is sufficient to achieve greater than 0.2 milligrams per litre across the network, will be introduced to the areas which have been unchlorinated.

Acting Head of Three Waters Brent Smith said “we know this will be disappointing for residents who’ve previously enjoyed unchlorinated water, but we have to take this step to comply with the law.”

“We’ve been working to update current chlorination equipment at our pump stations and are now ready to get it up-and-running.

“Some of our staff and contractors working in three waters have reported an increase in abuse in recent weeks. Please remember that our staff are just doing their jobs.

“When chlorine is introduced to an unchlorinated water supply there can be taste and odour issues as chlorinated water reacts with unchlorinated water and any naturally occurring biofilms in the pipework.

“Any taste and odour issues should reduce after a week or two, and we’ll be doing what we can to keep the chlorine dose to a minimum during that time.

Chlorine timing 

Brooklands-Kainga introduced later this week – suburbs impacted Brooklands, Kainga, Spencerville 

Parklands and Rawhiti introduced week 5 June – suburbs impacted Aranui, Avondale, Bexley, Burwood, Marshland, Mairehau, Parklands, Queespark, New Brighton, North New Brighton and South Brighton

Northwest introduced week of 12 June – suburbs impacted Belfast, Northwood, Casebrook, Harewood, Bishopdale, Burnside, Ilam, Avonhead, Redwood, Russley, Broomfield, Middleton, Upper Riccarton, Fendalton, Styx and Northcote

Birdlings Flat introduced week of 19 June