After finding that some below-ground wellheads could become contaminated during heavy flooding, the council decided on 25 January to chlorinate all drinking water for 12 months.
The chlorination began in late March and almost two months later, after complaints from hundreds of residents about the taste, Christchurch Mayor Lianne Dalziel asked staff to look at lowering chlorine levels.
"They are looking at a programme of work that they hope to refer to the drinking water assesor ... that would reduce the amount of chlorine in the water overall," she said.
She hoped the programme would be on the desk of the drinking water assessor by the end of today.
Ms Dalziel also acknowledged the chlorine was causing some problems, but refused to say if council staff were initially wrong about the affect it would have.
"Staff were optimistic and were in many respects trying to reassure people based on their experience after the earthquakes," she said.
"I think that staff have underestimated the impact that it has had on significant areas of Christchurch."
The council stated on its website that the chlorine dosage rate at each pump station is roughly one part per million, but does fluctuate.
Council staff have repeatedly told RNZ that people should barely be able to taste the chlorine.
Council city services general manager David Adamson said in April that people should not be able to taste the chlorine and, if they did, the taste would disappear quickly.
"There will be some people who notice it. The majority of people, we don't believe, will see much difference," he said at the time.
Christchurch residents which RNZ spoke to said that was not close to what was actually going on.
Avonside mother-of-three Michele Linda Shuker said the chlorination was having a dramatic impact on her family.
"My children have sick stomachs," she said.
"When I'm the last one to have a shower at night ... my eyes are so sore ... my skin is so flaky ... it's like swimming in a swimming pool."
Tui Paris, from South New Brighton, had a similar story.
"We've had to buy bottled water because its been giving everyone upset tummies ... when we bought bottled water everybody's sore stomachs disappeared," she said.
