Canterbury Regional Council has begun a major study of water resources on the plains area between the Ashley and Waimakariri Rivers.
The council will examine the amount of water entering the system from rainfall and runoff, what's being used for irrigation, and how much is lost through rivers and streams, evaporation and groundwater flows.
Hydrologist John Weeber says it will provide new information on the interaction between groundwater and spring-fed streams and the impact that extraction of water is having on supplies.
