Water quality

Reproduced by kind permission of Christchurch City Council

While many New Zealand towns get their water from rivers, Christchurch is different because its water supply is drawn from the artesian basin under the city.

Christchurch water is naturally filtered through the gravel beds and sand laid down by glaciers and rivers during the formation of the Canterbury Plains. This means that the water doesn't need to be filtered to remove bacteria or other matter, because it comes from the ground clear, refreshing and ready-to-drink.

Over time the underground artesian basin is recharged predominantly from the Waimakariri River, and also from rainfall that has seeped from the surface down into pores in the sand and shingle. 

The water-filled bands of gravel are called aquifers, underground streams designed by nature and replenished in the recharge zone. Sometimes the water flows naturally to above ground from the wells drilled into these gravel beds. These are called artesian wells.