Wider water-take limits are coming into force in Southland as river flows drop in prolonged dry conditions.
The Southland regional council says 45 properties and businesses have had to stop drawing water for a variety of purposes - including irrigation - after streams and rivers fell below limits in their resource consents.
Ten waterways, including the Mataura, Waikaia and Oreti Rivers are affected.
The catchment of the Upper Aparima River in north-western Southland has been hit hardest, being rated at severe dryness normally seen only every 10 to 25 years.
The council says the levels of the Upper Aparima and the Hamilton Burn will be extremely low by the weekend unless there is rain.
It says conditions are not nearly as severe as the drought in the North Island but are starting to have an effect.
It will decide on Thursday whether to convene Southland's water shortage response group.