Award-winning Te Awamutu dairy farmers John Hayward and Susan O’Regan don’t view the money they spend on environmental projects as a cost, but as an investment. Their business, Judge Valley Dairies, is committed to sustainability and biodiversity.
As one of 15 DairyNZ Climate Change Ambassadors, they have an “open gate” policy and a willingness to share their knowledge.
The 240ha farm has a 130ha dairy platform, 70ha for drystock, and the remainder is native bush, pine and manuka plantations, 11 wetland areas, two sediment dams, and fully-fenced waterways.
“We’ve chosen to plant the trees, and many of the riparian strips,” says John. “Planting on the marginal land, that wasn’t particularly productive as pasture, mitigates sediment, phosphate, nitrogen and E. coli loss, and creates diversity.”
Reducing nitrogen footprint
“The ultimate goal is to drop the footprint but keep the industry profitable,” says John. Judge Valley uses low N sires, to breed cows that excrete less nitrogen.
After joining Open Country Dairy in 2013, the farm milked 480 cows in a split calving operation but in a drive to become more sustainable they now milk 380 cows in an autumn calving system. John and one worker run the farm, and Susan is fully involved behind the scenes, while also carrying out her role as Kakepuku Ward Councillor at Waipa District Council.
The farm is now a System 2, with most feed being grown on-farm. The purpose-built feed pad utilises feed grown on the land effectively. “Before we had another worker, a bigger footprint, and were bringing in feed,” says John.
“We still make a similar profit because those extra cows covered the effort involved in maintaining and milking them.”
When John and Susan took over the farm in 2000, it had a dated and likely non-compliant two-pond effluent system.
Their system now allows them to wash down their feed pad with recycled water, which is then filtered through a weeping wall. To complete this project, 2019 has started with a further $100,000 investment in the farm’s effluent system.
“We’ve been designing a system that is affordable, futureproofed, and hopefully something people can see and replicate on their own farms,” says John.
A 1.3 million litre, flexible polypropylene-lined Kliptank has been centrally placed on the property. It is 29m in diameter and stands 2m tall. Despite its dimensions, the soft green-coloured walls blend into the surrounding pastures.
When John and Susan stand in the base of their empty tank – “the first and last time” they ever will – it gives a real perspective of its size.
The decision to get an above-ground tank was partly to do with the couple having young children, and feeling this type of tank posed less of a safety risk than an in-ground pond. So 500m of pipework has been laid to service the new tank.
The tank is hooked up to the existing hydrant system, and the new AgFirst WETA Low Rate Travelling Rain-gun. John’s eyes light up when he talks of the WETA irrigator.
“It runs on a turbine driven hydraulic winch system, powered by the effluent flow. It applies high volumes of effluent at low rates over large areas.”
With its ability to achieve wetted widths of up to 130m, the effluent has time to slowly soak into the soil and stay for longer in the rootzone of the plant, rather than running off or leaching away.
Along with current systems that are monitored by the farm’s HALO farm system, the new effluent tank and effluent irrigation records will be part of the data collected and used.
“There will be effluent level updates automatically every 15 minutes, with effluent application calculations made, and the amount used mapped and recorded.”
Effluent aeration and stirring
The tank will have two pumps and a stirrer. The innovative KlipJet Oxy Aerator Stirring System stirs and aerates effluent prior to irrigating the pasture.
“Not only will this process stop the tank from smelling, it will stir up the sludge and break the crust and introduce oxygen.
“In simple terms it’s a bit like the first stage of water treatment, the oxygen fixes to the nitrogen in the tank.”
That is good news for the environment as the nitrogen is already fixed and in a form the plants can immediately start taking up. As well as speeding up the usage of the effluent, it also reduces the amount of nitrogen leaching.
Although the tank will hold 1.2 million litres, that takes into consideration the 1100mm of rainfall each year falling onto the surface area of the open tank.
“If we need more holding capacity in the future, we can invest in a cover at a later date, and that will free up more space in the tank,” says John.
Judge Valley Dairies can now tick the box for being fully compliant with all the upcoming effluent management legislation.