• Grounded introduces

    The Ground Truth System

    Measure real nutrient losses on-farm.

    You can't manage what you don't measure.

Base environmental decisions on real measurements

The environment is important. Farmers have known this for generations, and preserved their local environment. And today, there are regulations to ensure that the environment continues to be protected. In New Zealand, farmers are now required by law to minimise nutrient loss to water.

However, there has been no practical way to actually measure nutrient leaching losses. So farmers are required to estimate what their nutrient losses might be, using models. And very critical decisions, costing in some cases many thousands of dollars, are made based on estimates alone.

Are these estimates correct?

Are farmers being fairly restricted, or unfairly penalised?

How can you know?

The GroundTruth System is a growing suite of tools and services that allows the direct measurement of leaching loss on-farm, in a range of situations. At present, the system can measure leaching loss from freely draining soils on flat to slightly sloping topography. This includes the soils of most critical concern in intensive arable, horticulture and pastoral farming. 

for Research

  • Measures leaching losses on-farm or in field plots (ie drainage, not runoff).
  • Accurate. Designed to achieve equal or greater accuracy in relation to leading university and CRI techniques.
  • Affordable. Minimises capital investment to allow funding from many sources.
  • Simple to use. Does not impede cultivation or grazing.
  • Versatile. Can measure Nitrogen, Phosphorus (leaching only), chemical residues, microbial losses...

for Management

  • Real-time. Rainfall and drainage volumes available immediately on your computer, with an estimate of nutrient concentration. Not just an annual accounting tool, can inform management today.
  • Measure actual nutrient loss from arable and horticultural crops that are not well supported by models. 
  • Check the accuracy of models, or use instead of models for specific situations.
  • Not yet certified for use for regulatory compliance measurements - talk to your regional council if you would like to use it for this.


Collects all drainage from a 10m long strip in a paddock. Can be positioned anywhere in a paddock. Averages variation in loss along that strip.

Equivalent size to 15 research lysimeters, 95 fluxmeters or 300 suction cups / electronic probes.


Measures drainage volume, and gives an estimate of nutrient concentration in real time.

Collects a drainage sample for chemical analysis. 

Solar powered, long range radio.

Child not included (provide your own).

Data management

Calculates nutrient leaching losses.  

Presents all data on a website in real time.

Remotely monitors all devices 

Alerts user when samples need collecting.