Banks Peninsula residents are being urged to start saving water as the region suffers from a lack of rain.
Rainfall in the area is the lowest it has been in a decade which is putting extra pressure on water supply for the towns there.
Christchurch City Council head of three waters and waste Helen Beaumont said supplies are fed by small streams which are exceptionally low at the moment.
"At this stage we haven't imposed formal water restrictions, but we're watching weather forecasts, stream flows and daily water use very closely. Even if we get scattered rain over coming days, it won't do much to change the overall situation with the streams."
People should take shorter showers, avoid watering lawns and check taps are not leaking.
Beaumont said the council also needs to abide by resource consents issued by the Canterbury Regional Council.
"We need to make sure we're not taking too much water from streams that are already very low. Taking too much has an impact on the ecosystem - the plants, fish and insects that live in the waterways - and the long-term quality of the water itself.
"If everyone pitches in and cuts back on their water use this summer, especially outdoors and in the garden, then everyone benefits," Beaumont said.