Latest News Archive

Please select Category, Year, and then Month to display items
Previous Archive
26 March 2018 Photo Pixabay
Back to the drawing board to save water
We’ve managed to damage nature’s ‘filter’ with air, ocean, and soil pollution, and by destroying wetlands.

Dr Cindé Greyling, a University of the Free State (UFS) DiMTEC (Disaster Management Training and Education Centre for Africa) alumni, studied drought mitigation with a strong focus on communicating important water-saving information. 

Can we run out of water?
Yes, and no, says Dr Greyling. “To our knowledge, water is not ‘leaking’ through our atmosphere. We have what we have, but that doesn’t mean we will have enough clean, fresh water forever. Nature has a magnificent way of purifying water through the water cycle. We, on the other hand, must use a lot of money and energy to purify water. Also, we’ve managed to damage nature’s ‘filter’ with air, ocean, and soil pollution, and by destroying wetlands. The other problem is a simple supply and demand scenario. More people will need more water, but not only that, population growth calls for industry development and increased food supplies – all of which require more water.”    

A war over water
Besides some Hollywood impressions, it is difficult to imagine a war over water, but it is possible. “Some experts are convinced that we are heading there, and others claim that such tensions already exist. Personally, I don’t favour these kinds of shock tactics (or truths) – social research has shown us that it rarely leads to behavioural changes. We can learn a lot from what was has been done in Cape Town. Although we all think people were bombarded with ‘Day-Zero’-scares, they were actually encouraged to adapt their behaviour with a communication campaign that hardly ever used the term ‘Day-Zero’. This approach mobilised citizens to reach record lows of water usage.” 

Adapt a new normal
Dr Greyling encourages the “new normal” set in motion by Capetonians. “Water consciousness is needed, even when the rain comes again. We’ve taken water for granted for too long. As consumers, we have the power to turn this situation around – drop for drop. Be aware about the amount of water you use, how you use it, and for what. Keep in mind that any wastage and pollution (of ‘dry’ things) also wastes and pollutes water. Generally, we need to behave better regarding consumption.”  

News Archive

Research helps farmers save with irrigation
2017-02-15

Description: Irrigation research Tags: Irrigation research

Marcill Venter, lecturer in the Department of
Agricultural Economics at the University of the
Free State, has developed the mathematical
programming system, Soil Water Irrigation
Planning and Energy Management in order to
determine irrigation pump hours.
Photo: Rulanzen Martin

Her advice to farmers is that they should make sure they are aware of the total cost (investment and operating costs) of an irrigation system. In most cases the investment cost is low, but the operating cost over the lifetime of the system is high.

“It is very important to have a look at the total cost and to install the most economic system,” says Marcill Venter, lecturer at the University of the Free State (UFS), who has done research on the economic sustainability of water-pipe systems.

Irrigation systems important components for farming
This research comes at a time when many farmers are relying on their irrigation systems due to persistent drought and low rainfall during 2016. South Africa has also experienced an abnormal increase in electricity tariffs in recent years. Due to tariff increases which threaten the future profitability of irrigation producers, the Water Research Commission (WRC) has launched and financed a project on the sustainable management of irrigation farming systems. “I had the opportunity to work on the project as a researcher,” says Venter.

The heart of every irrigation system is the water pipes that bring life to crops and livestock, and this is what Venter’s research is about. “Water pipes are part of the whole design of irrigation systems. The design of the system impact certain factors which determine the investment and operating costs,” she says.

Mathematical system to help farmers
Venter and Professor Bennie Grové, also from the Department of Agricultural Economics at the UFS, designed the Soil Water Irrigation Planning and Energy Management (SWIP-E) programming model as part of the WRC’s project, as well as for her master’s degree. “The model determines irrigation pump hours through a daily groundwater budget, while also taking into account the time-of-use electricity tariff structure and change in kilowatt requirements arising from the main-line design,” says Venter. The model is a non-linear programming model programmed in General Algebraic Modeling System (GAMS).

Design of irrigation system important for sustainability

The main outcome of the study is that the time-of-use electricity tariff structure (Ruraflex) is always more profitable than the flat-rate structure (Landrate). The interaction between the management and design of a system is crucial, as it determines the investment and operating costs. Irrigation designers should take the investment and operating cost of a system into account during the design process. The standards set by the South African Irrigation Institute (SAII) should also be controlled and revised.

Water-pipe thickness plays major role in cost cuts
There is interaction between water-pipe thickness, investment and operating costs. When thinner water pipes are installed, it increases the friction in the system as well as the kilowatt usage. A high kilowatt increases the operating cost, but the use of thinner water pipes lowers the investment cost. Thicker water pipes therefore lower the friction and the kilowatt requirements, which leads to lower operating costs, but thicker pipes have a higher investment cost. “It is thus crucial to look at the total cost (operating and investment cost) when investing in a new system. Farmers should invest in the system with the lowest total cost,” says Venter.

We use cookies to make interactions with our websites and services easy and meaningful. To better understand how they are used, read more about the UFS cookie policy. By continuing to use this site you are giving us your consent to do this.

Accept