Water shortages are looming as latest rainfall totals are revealed with not much respite in sight.
August will fall short of normal rainfall totals it was revealed today, making Marlborough one of the driest regions in the country
Speaking to Marlborough District Council’s Environment Committee on Thursday, environmental scientist – Hydrology Val Wadsworth says soil moisture levels are suffering.
“Marlborough is one of the driest regions in New Zealand – we are only ever six to eight dry weeks away from water shortage issues.”
It’s a big difference from just two months ago, she says.
“Only two months in 2020 – May and June – recorded above average rainfall across the district.
“Annual totals for the year to date are generally about 60 percent to 75 per cent for most of Marlborough.
“A few sites in the Sounds and Te Hoiere/Pelorus areas are up to 90 per cent of the year-to-date (YTD) total.”
Val says in some areas the July and August totals are less than half of the normal rate.
Eastern and Southern Marlborough are sitting at between 45 per cent and 65 percent with Northern and Western Marlborough coming in at between 65 per cent to 75 per cent.
“NIWA is predicting the next two months rainfall to be about normal. There is still time for some good spring rainfall and nature does sometimes tend to balance itself out, but it is not a given.”
“The rainfall over the last few days will be very beneficial for early spring pasture growth,” says Val.
“Despite this, more rainfall is needed in spring to further replenish soil moisture and river base flows for the coming summer.”
The steadily declining Wairau Aquifer will get a much needed boost from the snowfall earlier in the week.
Snow cover in the Marlborough high country is a significant contributor to summer flows, Val says.
“Good Wairau River flows are a key part of the recharge mechanism for the steadily declining Wairau aquifer.
“Pastoral farmers will be the first to feel the pinch if moisture levels don’t produce sufficient spring growth to carry into summer. Irrigators will also be affected if river flows fall to below cut-off levels early or for prolonged periods,” she says.
The Wairau River is flowing below average for this time of year, with flows at between 60 per cent and 70 per cent of normal and the Awatere is at 75 per cent.