Managing liquid assets

by Andy Bryenton

American inventor and scientist Benjamin Franklin once said ‘when the well is dry, you’ll know the value of water’. It’s a long way from being dry just yet, but the argument can be made that H2O is more valuable than gold, and that another famous quote will soon come true — ‘there are those who think water will one day become more valuable than oil, and those who know it’s already happened.’

The water industry — in terms of raw supply alone — tops a trillion dollars annually. And that’s without taking into consideration the single most important use of fresh water worldwide — feeding the planet as well as quenching its thirst. Farming uses a vast amount of water, but thankfully here in New Zealand we enjoy a waterrich environment, compared to places such as the Middle East or North Africa.

The ongoing challenge is to use it well, and to cycle it back into the ecosystem without significant contaminants.

Much of the water which falls on NZ as rain reaches the sea rather than the pasture, prompting Federated Farmers’ Conor English to say in 2011: ‘It’s not that New Zealand is running out of water, it’s that water is running out of New Zealand’. Capturing and using water wisely then, is the way forward.

And other countries with water issues more severe than ours point to an nformation-based approach.

Farmers in the United States West and Southwest are all too aware of water shortages currently, leading to the rise of advanced integrated information systems which can pinpoint exactly where water needs to be directed. In cropping and orchard applications this means implanting a wirelessly networked series of probes into the soil, with each of them reporting back to a central computer. A map of the land can then be built up with a detailed hydrographic analysis overlaid — showing which areas need irrigation and at what concentration. Taking things another step, even water reticulation and delivery systems can be placed entirely under computer control, with just the right amount delivered when it’s needed at the right time of the day, to prevent loss through evaporation. Leaks and loss can be identified faster and repaired before they become a large scale problem.

Large-scale irrigation has make more land arable than ever before, 
but managing water means outsmarting unpredictable weather

On a macro level, similar principles are being applied to irrigation-reliant areas worldwide, with feedback direct from the crop advising the best use and coverage of water from large-scale irrigation systems. Such systems can even pinpoint upcoming events well before a human operator, and can work in with the weather itself, taking rain, ambient humidity and dewfall into account when calculating a ‘water budget’ for top yield. The potential exists to combine information from soil hydration monitoring systems with nutrient maps to increase the effectiveness of fertilizer spreading as well, crossing over into yet another industry. 

Soil sensors deep in the substrate monitor water uptake 
and retention in this pasture

Many cutting-edge farming companies in New Zealand already offer hardware and software for water monitoring applications, so the competitive edge these systems offer is already being recognised in the field. As debate continues in several parts of the country about the necessity for large reservoir construction projects to bolster future water needs — and, indeed, as water use and its environmental effects continue to make news as an election year ‘hot topic’ — any methods of making the final delivery of water to where it’s needed more precise are sure to be welcomed. Seeing as most farmers now pack serious IT hardware on their person in the form of a tablet or smartphone, having all that info at one’s fingertips is easier than ever before.