Case Study – Fronterra – Optimisation of Pasture Irrigation using Wastewater

Fonterra is a global dairy company with a major processing facility at Darnum Park, Victoria. The facility manages a wastewater irrigation program that requires careful environmental oversight to maintain compliance and protect local groundwater, surface water, and pasture productivity. HydroTerra was engaged to design, implement, and manage an automated monitoring system to support these objectives.

Fonterra required a monitoring system to supplement and complement its existing environmental monitoring program at Darnum Park. The system needed to optimise wastewater irrigation while ensuring compliance with environmental regulations.
Existing challenges included:

• Soil analysis showed increasing solute concentrations that could affect pasture growth, and plant uptake alone was insufficient to mitigate this.
• Groundwater levels fluctuate, with unclear impacts from irrigation due to bore screening within a confined aquifer.
• Weather data was continuously measured but not recorded, making it difficult to integrate into irrigation modelling.
• Pivot Area 1 features two main soil types (A and C), but existing soil data did not provide enough insight for irrigation scheduling.

HydroTerra designed a monitoring system to centralise data collection, improve environmental oversight, and optimise irrigation. Key elements of the solution include:

• Surface monitoring: Rainfall, evapotranspiration, and surface runoff measured via an automatic weather station (AWS) and visual observations.
• Topsoil monitoring: Soil moisture storage and field capacity captured with soil moisture sensors, targeting silty clay zones and the upper 50 cm of the soil profile.
• Groundwater monitoring: Groundwater levels measured using soil moisture sensors and manual dip measurements at key aquitard and aquifer locations.
• Data integration: All measurements connected to HydroTerra’s DataStream™ platform, enabling automated data capture, centralised storage, and remote access.
• Manual field inputs: iPad apps developed to capture field data and provide automated safety reporting.

This system provides a more complete spatial and temporal understanding of soil moisture, groundwater, and weather conditions, supporting optimisation of irrigation rates while maintaining compliance.

The implemented monitoring system provides Fonterra with reliable, real-time environmental data to optimise wastewater irrigation. By combining soil moisture, groundwater, and weather monitoring with centralised data management and field data capture, the system enhances compliance oversight and supports sustainable environmental outcomes at Darnum Park.