The Otago Regional Council is warning thousands of farmers with consent to take irrigation water from rivers to conserve as much water as possible to reduce the pressure on rapidly dwindling rivers.
If farmers did not comply, they risked being unable to take any water at all until rainfall replenished supply, ORC environmental services manager Martin King said yesterday.
The warning was not unexpected, he said, with Dunedin having its driest December since records began in 1918.
"When you think we get an average of 80mm in Dunedin in December and this year we only got 9mm, you can see why we are asking farmers to be careful."
Staff were monitoring all Otago rivers daily and levels were rapidly dropping in the Kakanui, Shag and Waianakarua rivers in North Otago, and the Pomahaka and Waipahi rivers in South Otago, he said.
There were also concerns for some Central Otago rivers. While primary allocations from the Kakanui were still being allowed, permits for supplementary takes have been suspended until further notice.
Most rivers were likely to reach minimum flow levels in the next week or two, unless there was substantial rainfall. Once minimum flows were reached, farmers were unable to take any more water even if they had a consent, Mr King said.
While it rained briefly in Dunedin yesterday, it was not enough to replenish rivers, he said.
Further south, Environment Southland initiated the first stage of its water shortage response plan yesterday. Some farmers had been told to stop irrigating.
