When Aquifer Mapping's technology set to work at Tenterfield, New South Wales, last year, the town's reservoir was down to just 15 per cent capacity. It had 126 days' of water supply left.
The town's long-term future didn't look good; it didn't have enough water following a five-year drought," says John McKendry, a shareholder of Gisborne-based Aquifer Mapping Limited which uses skilled science to find hidden water – e-seismic technology developed by company founder Dr Michael du Preez.
"We understand they had already drilled seven dry wells," says McKendry. "We were called in and located a spot of interest that was drilled."
The new well they found started pumping more than 36,000 litres an hour – and while drought is one thing, many businesses, like food producers, dairy companies and wineries all want and need their own water supply, which is often hidden right beneath their feet.
Locating and tapping into underground streams in unscientific past years has often been down to guesswork, intuition and luck, says McKendry. Drilling decisions today are based on science and he has lost track of the number of times he's been called after a landowner has drilled several dry wells.
"A good recent example is a kiwifruit development company which drilled to 170m depth and found nothing. Aquifer Mapping were sent in; we found them an excellent supply at just 40m.
"Some farmers like to drill near power lines so there's an electricity supply for the water pump," he says. "Unfortunately, a power pole is not a reliable indicator of underground water."
Aquifer Mapping has worked all over the world locating underground water supplies for farmers, agriculturists, rural townships, and even fire departments. In New Zealand the team has been helping councils and landowners in places such as Whakatane, Tauranga, Rotorua and Hawke's Bay, plus working with irrigation companies and well-drilling firms across the country.
"We do a lot of work in the kiwifruit sector and more recently for some banks," he says. "In some cases, before a land purchase goes through, the banks' agri-managers are having us map and 3D model the new farms aquifers. This allows the banks the confidence that there is irrigation water available prior to settlement.
"The 3D models we prepare that show the aquifers and how they work are helping clients obtain water permits and that's where we add a lot of value —you can't just drill a hole in the ground and take the water, it's all regulated.
The Aquifer Mapping models we provide contain a great deal of valuable information for the likes of regional councils."
McKendry says climate change has had a big impact on their level of work: "Landowners are starting to realise how precious water really is; they have more respect for it, they realise there is a finite supply and they want to understand how they can manage their resources sustainably.
"That's one of the things that really drives me – I'm from a farming family as well. I want to know what's going on underground because it is just as important as what's going on at the surface."
McKendry says landowners relying on a constant supply of creek and river fresh water for their business are increasingly looking to establish their own source of aquifer water; they can't afford to be left high and dry if the local water company imposes drought restrictions.
Once on site, the Aquifer Mapping crews typically use machines mounted on side by side motorbikes to survey the property's boundary: "You don't often find a big lake of water underground. What we are looking for is flowing water passing through the land, so that's why we check the boundary first – to locate the water's point of entry and exit and find the fractures that allow more water to come through.
"Some people may think water is only found beneath low-lying areas but you can find it on hills too. We do a lot of work in the hill country and recently helped a farmer find water near the top of a 160m hill, just 30m below the surface. That well is delivering 8000 litres an hour via a solar-powered pump. A hill can often be well worth looking at."
McKendry says the technology his firm uses is highly complex but, in layman's terms, is a type of ultrasound that detects underground water.
Using a mixture of geological maps, its own 3D e-seismic software and advanced mapping – plus 12 years' research and experience – the firm can establish the likelihood of finding water.
"We have a global success rate of 86 per cent on drilled wells – that's very good considering we get called in to some very tough projects.
"Gone are the days of people wandering around with pieces of wire or willow sticks."
To find out more go to www.aquifermapping.co.nz.