Small-scale irrigation in Africa

This post is going to focus on the activities of small scale farmers with regard to their use of irrigation. There are many problems facing small-scale farmers in Africa (especially sub-Saharan Africa) and it is worthwhile taking a look into these in some depth. This isn’t to say it is all doom and gloom as there are a number of opportunities for people to improve their irrigation techniques and earn more money from their crops. Small-scale farmers often lack access to finance for irrigation, have a lack of support from governments and international organisations, are lacking in local water resource knowledge and efficient usage and are often in competition with large scale farms. These will be looked at to investigate the issues at play for small-scale farmers in Africa.

Aid and Finance for irrigation

An article from 2013 highlighted the key problems for farmers is access to irrigation - the fact that being small-scale farmers does not provide them with the finance to develop their irrigation methods and that the government and international aid is lacking in its support of these farmers. In sub-Saharan Africa, this problem is particularly significant as many countries are reliant on aid for a large proportion of their national expenditure. The Official Development Assistance (ODA) to agriculture has been on the decline. Support for the agriculture sector has dropped from 17% in 1980 to just 6% in 2008. This shows that funding has halved in the last three decades. This is especially disappointing as the majority of this funding is likely to be spent on irrigation projects and the development of irrigation for small-scale farmers is known as a method to escape poverty. It is however still possible for many small-scale farmers to fund their own irrigation systems. One of these is known as treadle pump which is a human powered pump that draws groundwater to the surface (Figure 1). These pumps can cost in the region of $20 -$100 and despite being expensive for poor farmers in Africa, it is not impossible to gain the funds. The next stage up from this are motor pumps which are more expensive but more effective at extracting groundwater.

Elsewhere in Africa, there has been a decrease in state funded irrigation schemes such as those in Northern Province, South Africa. This included the decline in funding for central pivot irrigation and has all occurred because the state engaged in the privatisation of many services to encourage local farmers to take responsibility for their own local resources. This leads on to the next section on water resource knowledge and management.

Figure 1: A treadle pump in operation.

Local water resource knowledge, usage and management

Another major problem for small-scale irrigators is that they lack the local knowledge of resources that are available to them and how to effectively manage them. In South Africa, there is growing water scarcity and this means that water management for irrigation is becoming even more important and will continue to do so into the future. This is a major problem compounded by the fact that the new water policy will hurt small-scale farmers even more as in the near future, subsidies will progressively decline and eventually they will need to pay for the water they use. The effective management of water for irrigation will be vital because of this. Unfortunately, there is a lack of mapping of the available groundwater across Africa, which leads to great uncertainty of the accessibility to water resources. It is not known how far down the water is, the volume of water stored in underground aquifers and the rate of groundwater recharge. These are all important aspects of the groundwater resource that need to be known and understood so that water is not used too quickly and is easily accessed. Adding this knowledge would clearly benefit efficient water use for irrigation. As I have mentioned before, I feel groundwater irrigation should be used as a coping mechanism (a way of adapting) for droughts and changes in rainfall as a result of climate change both on a seasonal and inter-annual time scales. This type of research is unachievable by small-scale farmers themselves and requires the support of much larger organisations who have the expertise and finance to carry this out.

Small-scale vs large-scale

Small-scale irrigators often have to compete with larger-scale farmers in a wide variety of ways. Financial donors face the tough decision over whether to finance large-scale irrigation projects that involve dams and reservoirs or small-scale irrigation systems. A paper from 2014 investigated the advantages of investing in small-scale irrigation projects over larger projects. The research found that there was a big opportunity for the expansion of small-holder irrigation in sub-Saharan Africa that would benefit farmers with improved incomes and reduced food insecurity. There are still concerns about the effectiveness of funding these projects as individuals often lack the knowledge to utilise the irrigation techniques and land tenure insecurity reduces funding for long-term projects. This is likely to be one of the main reasons behind the continued funding of larger projects at the expense of small-holder irrigation schemes.

To conclude, it is evident that there are many factors working against small-holder irrigation in Africa but there is still hope for farmers. This area provides great potential for expansion but only if resources (time, money, expertise) are invested in it. Small-scale farming is especially important for African economies and the livelihoods of families and this is why I believe that there should be an increased focus on promoting this area of irrigated farming for growth.

The Food Energy Water Nexus

Today I watched this interesting video by WWF South Africa on Youtube which highlights the key links between water, food and energy. It neatly summarises the issues that South Africa are undergoing (nicely linking to my previous blog post on South Africa). The video made me think about the role energy plays in the relationship between food and water. This is because the role of energy is often neglected. In other words, the focus with regards to water and food is on how to find and obtain more water, not how are we going to find the energy to obtain that water. The clip states that South Africa is currently in an energy crisis and therefore this is a key issue in the country.

The video also raised a point that struck me as unusual. The statement was ‘We need to produce more food with less water.’ To me this is very strange as the obvious ways to increase food production is through increased irrigation and therefore more water consumption. Researching this further, an article titled 'How to grow more food with less water' emphasises the importance of technology to achieve this. Sensors, satellites and software can be used to assess water demand for crops on a farm. New technology is even being developed right now:

“Susan O’Shaughnessy, a research agricultural engineer at the U.S. Department of Agriculture in Bushland, Texas, is developing new sensors for center-pivot irrigation devices to help farmers ensure that precious groundwater isn’t wasted. The sensors measure leaf-canopy temperature to gauge water demand, which helps avoid over-irrigating.” 

This advancement of irrigation by the use of technology is particularly important as around 40% of the world’s food grows on irrigated land. Improved use of water for irrigation through the implementation of technologies could reduce water demands of farms by up to 50%. This includes the use of drip systems that supply water slowly onto the crops, directly at the surface so that almost no water is lost through evaporation. It is clear that there are huge possibilities to make improvements to the irrigation of croplands.

Short videos like this one can help you to view an issue from a different angle and that is always important when studying a complex problem that requires new and innovative solutions.

No mention of groundwater?

A recent article published in Bloomberg titled ‘ “Catastrophe” Seen by S. Africa Agriculture Due to Drought’ caught my eye. South Africa, one of the most developed countries in Africa, is experiencing its worst drought in more than a century. As to be expected, agriculture is being hit hardest. This is exacerbated by the fact that rivers and dams are also running dry and that the drought may well continue into 2017.

The article highlights how the drought is incurring huge financial costs for individuals and businesses in South Africa with the government spending 268 million rand on drought relief. The recent El Niño event caused the drought here and a lack of rainfall since then has halted the recovery from this. This entire article, however, does not mention groundwater what-so-ever despite groundwater being useful during droughts. This encouraged me to look into South Africa’s access to groundwater and the use of groundwater to adapt to climate change.

Figure 1: (a) Groundwater storage measure in water depth (mm) and (b) total groundwater storage by country in Africa

As can be seen from Figure 1, South Africa is not particularly lacking in groundwater storage with eastern areas having around 10,000 – 25,000 mm water depth of groundwater and a reasonable recharge rate of 25-100 mm per year. It is also worth noting that South Africa has more groundwater than around two-thirds of countries in Africa. So now we know that South Africa isn’t lacking in groundwater, why wasn’t it mentioned as an irrigation technique in the Bloomberg article?

The groundwater in South Africa is located relatively shallowly compared to other areas of Africa as shown in Figure 2. This means that it is easier to extract the available groundwater and much greater amounts can be extracted using motorised pumps – as is necessary for irrigation. This gives extra weight to the argument for using groundwater in South Africa and questions why it isn’t being used more.

Figure 2: Estimated depth to groundwater (mbgl)

South Africa’s relationship with groundwater fed irrigation is interesting. As a result of the country’s apartheid history, much of the development and financing for irrigation was focused on White Farmers. This is particularly important as 80.2% of the population in South Africa is Black African. Further to this, irrigated land of White farmers was on average 10 times larger than those of Black farmers. The majority of Black farms are therefore small scale and the irrigation technology was directed to larger scale farms. These statistics help to show that the issues surround irrigation in South Africa are in fact related to the country’s apartheid history and the lack of access to irrigation technology and finances for many Black farmers. To me, this illustrates why South Africa is having such a ‘catastrophe’ with the droughts. The majority of small scale farmers lack groundwater access to keep their crops irrigated during this prolonged dry spell despite the water resources existing in (or under) their country.

Specifically regarding smallholder irrigation schemes in South Africa, just 3.0% of land that required irrigation used groundwater sources. This is incredibly low considering the large groundwater resources that are relatively easily available in South Africa as mentioned earlier. With reduced rainfall and rivers running dry, it is easy to see why crops are dying and small scale farmers are struggling. They simply are unable to access the groundwater beneath their feet that could help them during dry periods like the one they are currently in.

So what does the next year and the future hold for South Africa? Agriculture currently accounts for 85% of freshwater usage and total consumption for agriculture is expected to double by 2050. This increased demand for water alongside climate change is going to have significant impacts on irrigation in South Africa. Figure 3 below highlights that the relative increase in water demand for crops is going to increase more significantly in South Africa than many other areas. With South Africa dominated by a few large commercial farms and numerous small scale subsistence farms, the people of South Africa will be dearly affected by climate change. It is unknown how climate change will impact food production exactly in South Africa but some models predict that under wetter and warmer conditions, welfare in South Africa will increase due to an improved competitiveness in the food market globally. Whether South Africa will get wetter and warmer is again debatable and other future situations see the country far more negatively affected. 

Figure 3: Relative increase in crop water consumption

It is understandable that the Bloomberg article neglected groundwater in the piece on the South African drought due to its relative insignificance as an irrigation technique in the country. It is worth saying however that if the country could provide good access to the groundwater as a source of irrigation, it would improve their resilience to droughts and other impacts of climate change in the future. Personally, I believe that in South Africa’s case, groundwater usage should be limited to instances of extreme drought, and therefore only used sparingly in times of greatest need as the rate of groundwater recharge is low and sustained use could leave the nation short of water.

Welcome!

Hello and welcome to my blog looking into the relationship between water and food in Africa. I thought to begin with it would be useful to introduce this topic and why I have chosen to blog about it. One particular statistic peaked my interest in the relationship water and food, the statistic being that in 2000, around 70% of freshwater extracted was used for agriculture. To me this seemed high considering most of the water use that an individual can observe is used domestically in the form of showers, washing machines and water used in cooking. It isn’t obvious in day to day life how important water is to the food we eat.

As the majority of the water use is for agriculture, I thought it beneficial to investigate further the link between the two. The focus of this blog is Africa, an area of the world that has the biggest issues with water, food production and the effects of climate change.

Introducing this topic a little more, it is necessary to look at some key background data that show some interesting trends. The graph below (Figure 1) shows global blue water withdrawal up to the present and predicted into the future. Blue water just refers to surface water (e.g. rivers and lakes) and groundwater (water stored underground, I will look into this in more detail in future blog posts). This graph illustrates the significant proportion of water consumption taken up by irrigation which is predicted to increase into the future. Interestingly, household consumption is of relatively small importance but this is projected to increase into the future, likely as a result of global population increase.

Figure 1: Estimated and predicted water consumption, abstraction and withdrawal.

This is all very interesting but tells us little about the specific area this blog is looking at, Africa. So why is water for food so important in Africa? Firstly, the very warm climate means that a large proportion of rainfall is lost as evapotranspiration (evaporation and transpiration). This is problematic as it means much larger quantities of water are required to irrigate cropland. In addition to this, Africa contains many of the poorest countries in the world. The map below, produced by the World Bank, makes it obvious to see that the greatest proportions of people living in poverty are found in many sub-Saharan African countries. In some countries in Africa, more than half of people are living on less than $1.90 a day. This illustrates the struggle in Africa, both environmentally and economically and this has an influence on water usage and food production across the continent.

Figure 2: Map of share of the population living on less than $1.90 a day.

I hope this blog will be interesting and informative. I feel this first blog post has highlighted what I aim to achieve and has given a clear introduction to the importance of water to food production and the possible problems faced by people living in Africa. I plan to look into a number of different aspects of water and food, most importantly, the effect of climate change, the idea of water scarcity, groundwater extraction, virtual water and much more…