For a dairy farmer, there’s no more important resource — apart from cows — than water. Plentiful rainfall is needed to keep the grass growing and to replenish aquifers and water quality is vital for stock health and to meet dairy company standards.

So farmers Brendon and Ron Van Vugt, who farm 170ha of prime Waikato dairy country at Gordonton, are celebrating an upgrade to their water filtration system that has ended decades of frustration.

They have given up filtering their bore water supply through sand, installing a system that extracts troublesome impurities many times more effectively while also providing significant labour, electricity and water savings. And those are just the human benefits.

For their 580 dairy cows, says Brendon Van Vugt, cleaner water means greater milk production.

“It’s a no-brainer — we now have water that we can see through to the bottom of our troughs and the cows are drinking more and doing better.”

The Waikato, with more than a third of the country’s dairy farms, is rightly renowned as the heart of New Zealand dairying. But the locality where the Van Vugt family has farmed since the 1970s hasits challenges.

The water they pump from a 50m bore for their herd and for cleaning the farm’s 50-bail rotary dairy shed is comparatively high in iron and manganese. Too much iron can cause cows to lose body weight and limit their milk solids production.

Manganese, meanwhile, does nothing for water’s palatability, imparting a bitter taste. Add to that cloudiness, or high turbidity, and throw a little e-coli into the mix, and the result is water that failed to comply with dairy company Fonterra’s standard for plant cleaning.

“It’s a no-brainer — we now have water that we can see through to the bottom of our troughs and the cows are drinking more and doing better.”

Gordonton dairy farmer Brendon Van Vugt

So-called water exclusion meant close monitoring — at a monthly fee — to ensure no trace of bore water entered the milk the Van Vugts supplied Fonterra.

Like many local farmers, the Van Vugts had relied on sand filtration for removal of heavy metals from their water. But that was at the cost of slowing the rate of extraction from the bore to a level that was barely meeting the farm’s peak water use of more than 80,000 litres (80cu m) a day. Daily sand cleansing also took about 15 minutes and used the equivalent of several dozen cows’ drinking water.

“We couldn’t get a big enough volume through the filter to keep up with demand,” Van Vugt says. “So we were always on the back foot with water.”

When they increased the size of their herd from 530 cows to 580 three years ago, the pressure came on to upgrade the system.

“We’d been just getting by, but with the extra cow numbers, as soon as anything went wrong such as water loss through a leak, we’d find it almost impossible to catch up with demand again.

“Without water you can’t farm. So we had to look for a solution that used as little water as possible to maintain the system itself.”

Another incentive to limit water that went down the drain on sand cleansing was a change to the Waikato Regional Plan, variation 6, which was introduced to manage the region’s water use.

Dairy farms have a daily allocation based on land area and herd size, and with a new requirement to meter the amount they’re using, they can expect a “please explain” request from Waikato Regional Council if they go over their quota, Van Vugt says.

“It’s related to the fact that the number of cows being milked is just going up and up so demand keeps climbing.” The Van Vugts’ herd, for instance, has roughly doubled in size since they began farming at Gordonton.

Chris Temple, managing director of Temple Water Technologies, the New Zealand owned firm that supplied the Van Vugt filtration system, says heavy metals in bore water is a Waikato-wide problem. However, there can be variances in concentrations even on neighbouring properties.

The Van Vugts’ Iron-Man STS™ filtration set-up is therefore customised for their water supply. Using a proprietary absorption medium, it cuts the bore water’s iron content from 7.6mg/l (ppm) to less than 0.02mg/l and the manganese concentration is down from 0.31mg/l to less than 0.005mg/l.

The contamination that made the water non-compliant with Fonterra’s standard — turbidity and e-coli — is also removed by the treatment process.

Turbidity, caused by suspended particles in the water, has gone from 13NTU — so murky that it was difficult to see through — to 0.1NTU. The e-coli problem, which was a result of bird droppings entering the water via a poorly fitting storage tank lid, is solved by the addition of chlorine.

All that is achieved while delivering water from the bore at a faster rate than the old system and using the existing pumping and reticulation infrastructure.

Before the new treatment system was installed, Van Vugt says, they had been unable to eliminate e-coli from the water. “My brother and I just aren’t the sort of people who like to have something that isn’t right and having to be on water exclusion was a bit frustrating. Now our water clarity is better, the e-coli is gone and we’re no longer on water exclusion, which saves us the $100 a month we were being charged for extra milk monitoring.”

A reminder of the old system’s inadequacy can still be seen in rust-coloured staining in the dairy shed. But with cleaner water the stains are fading and iron build-up in the pipes around the farm is disappearing.

The entire system is running more efficiently, Van Vugt says, with daily consumption being met in about 17 hours of pumping versus the round-the-clock extraction that used to be required.

“It’s going to reduce wear, it will reduce early replacement of plant — it’s a significant improvement and we’ve been really happy with it since it was put in last winter.

“This area is notorious for iron and manganese and I’ve recommended our system to a number of people who’ve been running sand filters. Variation 6 means that with the large volumes of water required for maintenance they’ll become dinosaurs — they won’t be able to stay under their allocation.”


  • Van Vugt Brothers Farm
  • 170ha at Gordonton, 15km from Hamilton
  • Milks 580 cows
  • Peak water consumption about 83,000 litres/day


  • Improve water quality for stock and dairy shed cleaning
  • Increase water extraction efficiency
  • Reduce labour component of water filtration system


  • Iron-Man STS™ (single tank system) from Temple Water Technologies


  • Water meets dairy company standards
  • Electricity saving of about $1000 a year through reduced pumping
  • Water for filter cleaning cut from about 6 percent of total use to about 0.5 percent — equivalent to consumption of 66 cows
  • 15-minute daily filter cleaning time eliminated