Rain brings minimal relief from dry conditions
Posted on Friday, 6 January 2012 01:27 p.m.
Environment Southland has initiated the first stage of its water shortage response plan and is closely monitoring river flows, aquifer levels and water takes.
Yesterday’s rain had only minimal impact on Southland rivers, which are dropping steadily to levels normally seen in February or March. Scientific Officer Chris Jenkins said that compared with previous dry summers, some rivers were at record lows for January.
NIWA has just released the climate outlook for the next three months and is predicting average or below average rainfall with warmer temperatures in Southland, leading to soil moisture levels and river flows that are both likely to be below average. And while the Met Service is forecasting rain across the region next week, it’s not expected to be enough to alleviate the prevailing dry conditions.
Mr Jenkins said that without prolonged and intense rain, the Oreti River could drop to 4.5 cumecs at Wallacetown by the end of next week, and the Mataura River is likely to reach 11 cumecs at Gore by about the 15th. Environment Southland staff will be discussing the implications of these river levels with the Invercargill City and Gore District Councils.
Farmers are already dealing with the consequences of the prolonged dry spell, with some having to stop irrigating because rivers have dropped below the level specified on irrigation consents.
Compliance Technical Officer Ruth Williamson said that many of the 110-plus consents to take water for irrigation had cut-off levels included in their conditions but the trigger levels varied in different catchments and older consents were less likely to include cut-offs. Some consents allowed water to be taken from surface water and others were for takes from groundwater. As a result, the Council was fielding calls from people asking why their neighbours were able to continue irrigating when they themselves had had to stop.
Compliance staff are following up these reports, and also checking that where irrigation is able to continue, the amount is within the consented limits.
A small number of householders relying on bore water have also starting to complain that their bores have run dry, while irrigators were continuing to operate in the area.
Groundwater Scientist Clint Rissmann said that some of these reports had been made anonymously, with made them impossible to investigate. The Council needed details including the physical locations, to check the bores and underlying aquifers.
Chief Executive Ciaran Keogh said that Environment Southland would make as much information as possible on the region’s water resources available to farmers and major industries to help them plan to cope with a prolonged dry period. It was also important for the community to be confident that water was being allocated and used fairly and consistently, so the Council would look at consent conditions which were allowing some major water abstractions to continue without restriction.
The next stage of the Council’s water shortage response plan would include convening a wider group of farming, industry, iwi, environmental and community representatives. This would be considered next week if there was no significant rain in the meantime.
Environment Southland is the brand name of Southland Regional Council.