There are calls for for Cantabrians to use less water this summer if they don't want chlorine in their drinking water.

The Christchurch City Council is repairing and resealing 95 underground well-heads which were found to be vulnerable to contamination.

This led to controversial temporary chlorination of the city's drinking water.

Water supply improvement manager Helen Beaumont says they are running a campaign asking people to reduce water use over the summer.

"We need to take some wells out of service to repair them, which they can't do if the usage is too heavy. We could be set back up to four months on finishing the repairs."