Irrigation Good Management Practices

Irrigation GMP 1: Manage the amount and timing of irrigation inputs to meet plant demands and minimise risk of leaching and runoff.

To meet this GMP you must

  1. be able to demonstrate why you chose to irrigate and justify the amount you used.

Things you can do:

  • Install and use an objective tool to monitor soil moisture deficit, such as an Aquaflex tape, soil moisture probe, a scheduling service or a soil water budget
  • Keep irrigation, rainfall, and PET records
  • Keep records of when you irrigate for some other reason, such as to wash in fertiliser or to activate herbicide.
  • Make sure you are irrigating the land and not the road, watering the road is no only a waste of water but can create safety risk for motorist. MHV’s water take consent also prohibits irrigating the road.  

Watering road

Irrigator irrigating the road.

Irrigation GMP 2: Design, calibrate and operate systems to minimise the amount of water needed to meet production objectives.

 To meet this GMP, you must ensure:

  1. All new irrigation systems are designed and installed according to industry code of practice standards
  2. Install a water meter on your dairy shed water take
  3. Maintain and regularly calibrate your irrigation system to optimise efficiency
  4. All staff (including you) are adequately trained

Things you can do:

  • Make sure you use an accredited irrigation designer when you build or upgrade your irrigation system
  • Make sure your new irrigation is commissioned properly, and include this as a requirement in your contract with the irrigation installer
  • Keep your design spec information on hand, such as design flow rates and pressures, maps, nozzle charts etc
  • Regularly check your irrigators such as a winter service, unblocking and replacing nozzles and pressure regulators, cleaning out sand traps and re-aligning your pivot to make sure the gun turns on and off when it needs to
  • Complete a bucket test every year, or check the pressure and flow rates of your system regularly
  • Keep records and invoices of maintenance you do on your system, you never know what patterns you might pick up
  • Make sure staff are trained up to your system and have the information they need to keep everything working as it should.

Good irrigator performance

Calibration of irrigation systems with bucket testing.


Poor irrigator performance

A poorly performing irrigator spreading water unevenly.



Irrigation NZ Soil Moisture Monitoring Guide

Dairy NZ Soil Water Budget

Irrigation NZ Certified Irrigation Designers

Download the Bucket Test app

Irrigation Records Calendar

Learn more about why bucket tests are a useful check  

Irrigation New Zealand  irrigator maintenance records sheets

All MHV shareholders and their staff can attend our training workshops for free. Keep an eye out for these on our Events  page.

IrrigationNZ run numerous training days to upskill yourself and your staff on efficient irrigation management.

MHV Water Ltd
326 Burnett St
Ashburton 7700

Phone: +64 3 307 8389