Water scarcity

Water Scarcity: South African Agriculture must find a Technological Advantage

Despite South Africa’s continuing slow economic growth – projected by the Reserve Bank at just 1.6% for the 2017 year, the 3rdquarter of 2017 revealed surprising upward trends in a number of sectors, amongst them agriculture.

The government’s Crop Estimates Committee raised its 2017 maize harvest forecast in September by a further 2.2% from its August forecast. With near “miraculous” rain breaking the stranglehold of drought in the maize-growing regions in May, the 2017 maize harvest is expected to reach 16.744 million tonnes compared with 7.78 million tonnes in 2016. Agriculture is likely to maintain the 21.2% year-on-year growth it achieved in the second quarter. Alongside mining, agriculture is emerging as a “saviour” sector for the South African economy, making cost and production efficiencies all the more important. Technology will continue to play a significant role in assisting farmers to extract the maximum amount of yield from an increasingly difficult sector, plagued by droughts, labour unrest, security concerns and land rights uncertainty.

Rainfall and water consumption must rank as the most critical risk factor currently facing South African farmers. The Western Cape’s ongoing drought is projected to cost grape farmers in that province R500m, and 30 000 animals in livestock have already had to be sold or destroyed due to the drought. Anecdotal evidence shows many fruit farmers are removing the blossoms off their trees, in order to preserve the tree for following seasons, as there is not enough water to bring the buds to fruition.

So where does technology come in? A computer can’t, after all, make it rain. However, water scarcity demands a per millilitre approach to water usage, and farmers that track their soil conditions, humidity, dam levels and orchard/field specific temperature conditions on a micro-climate basis may be surprised at how the data can impact on water savings and usage.

Let’s briefly explore a few examples of how networked remote sensors can assist in major water saving efficiencies.

Water Pressure

Water pressure is a key indicator of successful irrigation. Constant water pressure is required to ensure effective water distribution – when water pressure drops it not only means that a section of the irrigation system is compromised by a burst or leak, but also that sprayers are not effective – meaning water wastage. With remote sensors applied at key locations throughout the irrigation systems, farmers will be immediately notified of pressure drops. The system can also allow for immediate cessation of irrigation – either manually from the farmers phone or computer – or automatically if water pressure drops below an agreed level. This way, precious water is retained while repairs and adjustments are made.

Dam Levels

Dam levels can be monitored via remote sensors that physical measure the water surface, or by measuring the dam’s overall water pressure. A compromised dam’s water level will drop significantly faster than anticipated drops from irrigation. This would mean that the damn is being compromised, and is leaking. Immediate notification of this would mean that immediate action could be taken to reinforce the dam wall, and prevent further water loss. Dam levels, in relation to shared water schemes, are also an important factor in establishing if farmers are receiving their full allocation from a water scheme. The dam level monitoring system can be improved by adding water flow sensors on channels, programmed to measure water flow over the period of the farm’s shared water period, immediately informing the farmer if the full allocation is not reaching his dam.

Soil

In 2012 the US Department of Agriculture discovered that more than three-quarters of American farmers irrigate based on observable crop conditions, such as the way a leaf shrivels in the heat, or how dry the soil appears. Nearly 7 percent simply irrigate when their neighbours do. Many South African farmers also irrigate based on instinct, habit and the visual appearance of the orchard, field or vineyard. This is not necessarily an accurate way to establish which areas in fact require water at any given time, and can lead to massive water wastage. Soil monitoring is a precise means of measuring which areas of the farm require water, it can even be calibrated to measure specific micro-areas with a given vineyard or orchard. Using precise scientific measures (sap flow, soil hydration etc.) the sensor can measure when precisely certain groups – or even individual plants - will require water, taking the guesswork out of irrigation practices. Read a fascinating case study from Napa Valley at WIRED magazine here. Through using remote sensor technology, two Napa vineyards saved a massive 37 million litres of water a season, between them.

The water shortages in South Africa are dire, and whilst the drought (the longest in recorded history in the Western Cape Province) will invariably break, the weather projections for the next half-century indicate increasingly dry conditions. Water usage, saving and retention must therefore be approached with evermore care and consideration – part of this approach must be an increasing trust in, and reliance on, already available technologies that have the power to save not only millions of liters of water, but 1000s of jobs, and millions of Rands.

The Xemote Difference

Xemote is a South African product, and unlike other systems is not imported. This means our clients benefit from local support capabilities, that feed into a full solution tailored directly to the scope of their needs. Xemote is produced by Xpitec (Pty) Ltd, one of South Africa’s leading electronic engineering and software development companies.

The Xemote product is widely used in agricultural applications, where it is provided alongside a physical hardware platform that any sensor can be connected to, ranging from pressure, temperature, digital inputs e.g. proximity switches and relays, analogue inputs, and they can also communicate with other intelligent devices. For agricultural applications, wireless sensors are ideally suited for fast in-field deployment without expensive wiring. For installations where power is not available, Xemote employs ruggedised and vandal proof solar enclosures for its GSM gateways. Monitoring of reservoir levels at our Balfour installation is a good example and has been in operation since September 2016.

Furthermore, we provide the complete monitoring chain. From data collection, transmission via the GPRS network, storing of collected measurement data on hosted servers, data retention, data security, and finally the presentation of the data to end users. Data presentation is provided to any authorised user with an internet connection (mobile or desktop) via a web browser.

These solutions can furthermore integrate into a larger Business Intelligence System, providing clients with timeous information on the processes, saving both time and money.