Be a smart irrigator this season

Why irrigation efficiency matters

The main environmental risks from irrigation are overwatering or non-uniformity of irrigation, which can lead to runoff and leaching of nutrients (nitrogen and phosphorus), sediment and microbes.

“As an irrigator, you can make a positive contribution towards reducing leaching and runoff in your catchment by integrating efficient irrigation practices into your farming system,” said water and land central team leader Marcelo Wibmer.

“Improved irrigation efficiency can lead to savings in operating costs, water use, improved pasture and crop production, reduced fertiliser loss and it can help improve overall water quality.”

The savings associated with increased irrigation efficiency can be significant. According to LandWISE, increasing uniformity of water from 0.7 to 0.9 can allow 50 per cent more area to be irrigated from a certain volume of water.

Using the right pump can reduce an electricity bill by 30 per cent.

Pre-season irrigation checklist

Spring is the time to check your equipment and make sure your irrigation schedules are ready for summer. Here are some things you can do to ensure you are ready to irrigate efficiently:

• Plan for the season: be ready to manage your scheduling under restrictions and identify higher production areas to concentrate on for the best return.
• Undertake maintenance: make sure your flows and pressures are within 10 per cent of operating design; check your system for leaks and broken sprinklers and make sure your end guns are aligned and operating as they should.
• Evaluate your irrigation performance: undertake a bucket test once a year. This helps determine the application depth, rate and how uniformly water is being applied during irrigation. Keep in mind it may be required as part of your consent conditions and FEP audit.
• Monitor your soil moisture: improve irrigation efficiency by implementing soil sensor technology in irrigation scheduling.
• Get accurate weather forecast information: weather and evapotranspiration data allow you to take advantage of rain and avoid irrigating when the conditions are not ideal.
• Upskill staff: training on scheduling and operation helps optimise water use and avoid damage to equipment.

Meeting Farm Environment Plan (FEP) audit requirements

Our FEP framework includes irrigation as a management area. As a bottom line, irrigation design and operation should minimise the risk of nutrient leaching to groundwater and runoff to surface water, to ensure the protection and buffering of mahinga kai value sites such as springs, wetlands, water courses, and drains.

Under the Canterbury Land and Water Regional Plan, consent holders have a responsibility to manage irrigation. A robust FEP audit process is a key instrument that assures the community that this objective is being achieved. Auditors verify the on-farm practices against the objective and four targets relating to:

• installation
• maintenance
• decision-making
• training

More information on irrigation Good Management Practices is available on the Farmers' Hub.

Commissioning tests for new systems

If you have recently installed irrigation equipment, you will need to get a commissioning test to ensure your equipment is set up efficiently and is safe for staff to operate. A commissioning test also provides a performance baseline that can be used as a reference point for future performance assessments of the irrigation system.

We’re here to help with irrigation management

Our land management team are available for any support or guidance around irrigation good management practice. They can:

• Carry out an irrigation risk assessment with you
• Discuss current irrigation management practices on farm
• Pinpoint what’s needed to achieve a high level of confidence in irrigation management
• Discuss the evidence needed to demonstrate GMP in irrigation
• Discuss the value of bucket tests and show you how to undertake one
• Work with you on a ‘to do’ list with timelines to help you reach your goal.

Further help: If you have any questions about irrigation management, please contact your local land management advisor for advice.