In response to a surge in inquiries about the temporary chlorination of Christchurch’s drinking water, we've put together some information explaining why some are detecting high levels of chlorine in their water while others can barely notice it.

Why can some people taste and smell chlorine in their water and others can’t?

The chlorine dosing takes place at the pump station, not the individual well heads as some seem to think. From the pump station, the water flows directly out into our water reticulation system across the city. If you live close to the pump station, the chlorine dose you get coming out of your kitchen tap will be higher than if you live much further away.

Why does the taste and smell sometimes fluctuate during the day?

We have more than 50 pump stations across the city. While you’re primarily supplied by one pump station, if you are at midway point between pump stations, sometimes you may be getting the water from one pump station and sometimes you may be getting the water from the other. The level of chlorine in those pump stations may be different.

There are three pump stations where the well heads are secure and there is no chlorine at all. We will continue to focus on securing pump stations so we can further reduce the chlorine load.

Want to know more? Head over to Newsline to find out about how the condition of the pipes affects the smell and taste, as well as our testing regime and how we compare to other cities.

Medical Officer of Health Dr Cheryl Brunton has some advice for people who find that the treated water irritates their skin.

Dr Brunton explains that people with eczema often experience flares or exacerbations due to changes in the environment, particularly exposure to things that tend to dry the skin out.

"For some people with eczema, they might find bathing in chlorinated water tends to dry their skin out or irritate it.  If that’s the case they need to use plenty of emollient cream and treat any flare up of their eczema as they would usually do.  If it gets worse, they should see their GP or skin specialist."

Dr Brunton says there isn’t any evidence that eczema is more common in cities and towns with chlorinated water supplies.

There is background information and a map on our website showing areas of the city where chlorine is being used and this will be updated as we progress. There is also a question and answer section on the Council website.

You can call the Customer Contact Centre on 03 941 8999 or 0800 800 169 if you have any questions, or email watersupply@ccc.govt.nz