Water Treatment for Dairy Farms
Compliant water for your dairy shed.
Farm dairy water that passes
The water you use to clean your milking plant can touch your milk, so it has to meet MPI standards. Your Farm Dairy Assessor checks it for E. coli and clarity, and a failed result means a water-use plan, extra rules and, for Fonterra suppliers, extra costs.
We test, design, install and service water treatment for dairy sheds across Rodney and North Auckland, from the bore, spring, stream or roof right through to the wash tub and hot water cylinder. If the same supply feeds staff houses, we make that water safe to drink too.
Failed a water test?
Call Steve on 0800 278 296.
Why farm dairy water fails
These are the problems we find most often in dairy shed water.
E. coli
The most common reason for a failed test. It means animal or bird waste is getting into your water.
Giardia
Common in streams, dams and roof water. Normal chlorine doses don’t kill it, so UV is the reliable fix.
Iron and manganese
Often found in bore water. It makes water cloudy or stained and can fail the clarity check.
What your Farm Dairy Assessor checks
Water that can touch your milk has to meet MPI standards. Your assessor checks three things:
- E. coli: none in 100 mL, tested every three years by an approved lab
- Clarity: no more than 5 NTU, checked every year
- A risk checklist for your water source, every three years or when the supply changes
This covers water used to rinse and clean the milking plant and vat, including water going into the wash tub and hot water cylinder, and water milkers use to wash their hands and arms.
New since July 2025: water with a lot of sediment, or turbidity over 20 NTU, must be filtered before it’s treated.
Water that fails needs a water-use plan your assessor accepts, and Fonterra suppliers can be put on temporary water exclusion until it’s fixed. Sources: MPI farm dairy code (NZCP1) and Fonterra water factsheet.
One team, start to finish
From the water source to the wash tub, we can take care of:
Onsite visit and water testing
Filtration and UV sized for your shed
Iron and manganese removal
Tank cleaning and pipework
Safe drinking water for staff houses
Yearly servicing and lamp changes
24/7 emergency call-outs
From first visit to compliant water
One local team for the whole job, with as little disruption to milking as possible.
1
Onsite visit
We look at your source, tanks, pipework and how much water the shed uses at its busiest.
2
Water testing
Accredited lab tests for E. coli, clarity, iron and manganese, so we know exactly what we’re treating.
3
A plan for your assessor
A system design and written plan you can show your Farm Dairy Assessor.
4
Filtration
Sediment filters and a fine 1 micron filter, so the UV can do its job.
5
UV treatment
UV sized to the flow into your wash tub and hot water, to kill E. coli, Giardia and other bugs.
6
Tanks and lines
We clean out tanks, flush the lines and replace perished hoses, where contamination often hides.
7
Installation
Our registered plumbers install everything, planned around your milking times.
Compliant water for the milking plant
Clean water from source to shed
Tanks and pipework kept clean
On water exclusion, or worried about your next assessment?
Call Steve. We’ll find the cause, fix it and get your water back to compliant, with as little disruption to milking as possible.
Don’t just take our word for it…
⭐⭐⭐⭐⭐
“Steve came out and quoted on installing a UV system and tank filter, which I accepted and was promptly installed. Everything went as expected and site was left clean and tidy afterwards. Steve was great to deal with and gave us some tips for our bore as well. Strongly recommended as great local firm.”
Linda Matheson, Kaipara Flats, 2020
⭐⭐⭐⭐⭐
“This company has been servicing our water filtration system for 9 years now and we have always been very happy with the results. The service person has always been very helpful with information to guide us on what we should be aware of.”
Marilyn Wheeler, Kaiwaka, 2025
⭐⭐⭐⭐⭐
“Outstanding service. We have been with Steve and his team for over almost 20 years now and feel secure in the expertise and support they have provided to us in the past and going forward. Absolutely your go to for safe water provision.”
A. B., long-term customer, 2026
Why farmers choose Aqua Works
We’ve been treating rural water across Rodney and North Auckland since 2000, from bores and springs to streams and roof water. We also provide commercial water treatment for schools, cafés and other businesses.
- We test first, then design treatment for your water
- Systems sized for your shed at its busiest
- Installation planned around milking
- Records for your Farm Dairy Assessment
- 24/7 emergency call-outs
Local expertise. Local trust.
Four of our team have passed the NZQA small drinking water supplies course, and four have passed the NZQA course on writing Drinking Water Safety Plans.
Dairy farm water FAQs
What does a Farm Dairy Assessor check about my water?
E. coli, with none allowed in 100 mL, tested every three years by an approved lab. Clarity, no more than 5 NTU, checked every year. And a risk checklist for your water source every three years, or when the supply changes. Tell your dairy company and assessor straight away if you change your water supply.
Which water on a dairy farm has to comply?
Water used to rinse and clean the milking plant and vat, and to wash milkers’ hands and arms. That includes water going into the wash tub and hot water cylinder. Water for teat cleaning and milk cooling must be visually clean and fit for purpose.
What is temporary water exclusion for a dairy farm?
A plan your Farm Dairy Assessor approves so non-compliant water can’t touch your milk. Fonterra’s water factsheet lists extra steps for suppliers on exclusion, like treating rinse water and running milk to waste at the start of milking, plus a monthly charge and a tighter trigger for milk quality downgrades.
How does a dairy farm get off water exclusion?
Fix the cause, then have your water re-assessed. Fonterra’s water factsheet says it pays for the re-assessment once the work is done, and refunds that season’s exclusion charges if the water passes. Check the current details with your Farm Dairy Assessor.
Does UV work for dairy shed water?
Yes. UV is one of the most common fixes. It needs a 1 micron filter in front of it, a new lamp every 12 months and a clean quartz sleeve.
Can I put a chlorine tablet in my dairy shed water tank?
Not a pool tablet. Anything used to treat farm dairy water must be on MPI’s approved list, labelled for farm dairies, used at the label dose and checked after dosing. Overdosing can affect your milk and wear out rubberware faster.
Why does my dairy water pass at the source but fail in the shed?
The problem is usually in between: a dirty tank, biofilm in the lines or a perished hose. We clean the tank, flush the lines and replace hoses, then retest.
Does a dairy farm’s water source need protecting?
Yes. MPI’s farm dairy code keeps stock at least 10 m from a surface water intake, and effluent ponds, septic tanks and fuel at least 45 m away. Bore heads must be protected from effluent, chemicals and ponding water.
Do dairy farm staff houses need treated water?
Staff need safe drinking water. A supply for 25 people or fewer that’s only for household use doesn’t need to register. If it serves 26 or more people, or also provides drinking water at work, like at the dairy shed or a staff lunchroom, it needs to register by November 2028 and fully comply by 2030. We can check where your farm fits.
Our bore water is cloudy or stains. What can we do?
That’s often iron or manganese. We test first, then remove it with aeration, settling or filtration, so your water passes the clarity check.
Compliant shed water, every assessment
Book an onsite visit. We’ll test your water, fix the cause and look after your system, so your next Farm Dairy Assessment is one less thing to worry about.