ODT: Groundwater nutrient focus

Colin Williscroft and Rebecca Fox write in the Otago Daily Times about a consultation meeting to be held on the subject of increasing the maximum groundwater take by almost 0.8 million cubic metres a year.

A GNS scientist has said that allocation limits are important, as overly low levels of water in aquifers could draw in nitrate-contaminated water from elsewhere.

An excerpt: (read in full here)

“”His research on the effect of irrigation and dairying on groundwater had shown border strip irrigation posed a significant health risk to the farmers who used aquifers for their drinking water, but spray irrigation had little effect.

“”GNS Science groundwater section manager Dr Chris Daughney said allocation limits were very important, as, if too much water was taken out of an aquifer and the water table got too low, nitrate-laden water could be drawn in from other areas.

“National Institute of Water and Atmospheric Research assistant regional manager Graham Fenwick said nitrate contamination of groundwater also put the biodiversity of aquifers under threat.”