Agriculture is the most important industry in Africa. It employs more than half of working population and the figures obtained by your blogger last week show that in 2016, the gross value of irrigated agricultural production rose by 6 per cent compared to same period in 2015. This mainly happened in East and Southern African countries. Irrigated production accounted for 39 per cent of the gross value of agricultural production, which was up 2 per cent to more than 2015. According to the data, the highest value irrigated commodities were fruits followed by dairy products and vegetables, accounting for 70 per cent of the total for 2016 with South Africa, Egypt, Morocco, Ethiopia and Algeria leading the pack. The value of most irrigated commodities rose from 2015 except for cotton and cereals due to reduced water availability and unfavourable growing conditions. Also most countries experienced erratic weather patterns with Eastern African countries being the most adversely affected.Value of Africa’s irrigated agriculture was mainly on rice for grain, cereals for grain and seed, cotton, sugarcane, nurseries, cut flowers and turf, hay, vegetables, fruit, dairy production, meat cattle, sheep and other livestock. Water is a finite but crucial resource in African countries. In most river basins around the continent, water is diverted for industrial, municipal and domestic consumption with a good example being River Nile that starts in Uganda and flows all the way to mediterranean in Egypt. It’s also a critical component of wetlands and other natural ecosystems that are of tremendous value to countries commonly known as Nile basin countries. The bulk of water use in Africa is tied to agriculture and it accounts for approximately 59% of water diverted from natural sources for human use and 76% of water consumption. In the arid Southern and Eastern African regions, it’s not uncommon for irrigation to represent 80%-90% of all diversions.Much of the development that’s made these diversions possible is the subsidies by the central governments. This, together with water rights mechanisms that tend to preserve agriculture’s favoured access to the water supply, has made water relatively inexpensive for agriculture. Few farmers have had much incentive to achieve greater efficiencies in their use of water for irrigation. As a result, the amount of water being diverted for irrigation in Africa is about three times as much as is needed for crop production. On average, more than half of the water diverted for irrigation percolates into the groundwater or returns to surface streams without watering crops.According to 2016 data, about 25% of Africa’s total food supply came from irrigated land and in the Nile basin countries, the irrigated fraction of their agricultural land has reached 50%, but this relatively small area produced half the total crop value. As the African population grows, demand for food will also grow. Only a tiny minority of the required increase in food production can come from expanding development of arable land, or by increasing the number and types of crops grown per year. The remaining could be met with yield increased and better water use efficiency.As African population increases, the demand for water for non agricultural purposes will also grow.The water demand is estimated to increase by 40% between 2016 and 2040, and most of this increase will come from manufacturing, electricity production, and urban and domestic use. So in a drier Africa as witnessed over the last few months in countries like Nigeria, Somalia, Somaliland, Ethiopia and Kenya getting the amount of water used by irrigation under control is a necessity. New technologies might go a long way toward helping African countries reach that goal.
Over the past five years, new technologies have been developed to decrease on-farm irrigation losses. One of the technology being used in South Africa used drone-guided equipment to level the field so that water will flow uniformly into the soil, not run down any little hills or collect in little gullies. It also makes it easier to limit the amount of water that seeps beneath where the roots of the crop can reach. The systems also improve the uniformity of water application, reducing the amount of water lost to deeper percolation or runoff from the field. Although the technology is expensive, it helps reduce the costs of other inputs to production.Monitoring and information technologies are also helping reduce water losses at both the system and farm levels.In Morocco, Egypt and Algeria it’s now possible to use a supervisory control and data acquisition system to provide precise, integrated control over an entire irrigation system, in real time. The system automatically measures the amount of water available in reservoirs, quantities of water flowing in canals, and amounts of water being diverted onto fields. Also, the systems also can be used to easily and remotely control releases from reservoirs, diversions into canals. The users of the system, typically reservoir and canal operators, but also individual farmers can easily see where all the water is and how it’s being used, and they can make better decisions for what to do next with respect to releases and diversions.Outside of South Africa, Algeria, Morocco, Egypt and Tunisia, relatively few farmers or irrigation system operators currently use remote sensing as a source of information to reduce losses and improve irrigation efficiency. But this is changing as the cost of newly emerging technologies declines and as the information they produce becomes more readily available.It is possible now to use satellite imagery to estimate quantities of water used in individual irrigated fields almost anywhere in Africa. Although currently being used in South Africa only, the system also allows reservoir operators to monitor total water use in the areas served and better anticipate future irrigation demands for the entire system.In Kenya, an agri tech company is expected to start piloting unmanned autonomous systems to monitor agricultural systems, acquire scientific imagery and provide information for the operation of irrigation systems. Also known as drones, the systems will also support more efficient fertiliser applications, weed and pest management, and harvesting. If drone technologies becomes affordable in Africa, they will potentially provide very valuable information about when and where to apply precise quantities of water to the crop. Farmers with the right irrigation technology could use such information to accurately apply irrigation water at varying rates throughout the field rather than the same rate everywhere, which can lead to waste.As African water demand increases, the competition for a fixed water supply will become more difficult to manage, especially in arid and semi-arid parts of the continent and places where populations will grow rapidly like Uganda, Tanzania, Nigeria and South Africa. Since water use in irrigated agriculture is generally very inefficient, and since the economic value of water for agriculture is typically much lower that it is for African cities and industry, most likely there will be a natural trend to reduce water allocation to agriculture in favour of other uses. It is therefore very important for water sector policymakers in Africa to understand these trade-offs and how alternative schemes for water allocation will have economic, environmental and social impacts. As witnessed with the drought in horn of Africa recently, the climate change will increase the uncertainty in future water supplies in African countries and water management institutions will have to operate with greater flexibility in order to respond effectively to shifts in both water demands and supplies. New technologies will be the only tools needed to fit in Africa’s agricultural uses going forward.