Ground water is more available for rural communities to use compared to restricted flows of rivers which are restricted to channels.
This was said by Seifu Kebede, a hydrogeologist at the School of Earth Sciences, at Addis Ababa University, and author of more than 35 peer reviewed scientific articles and a book entitled "Groundwater in Ethiopia: features, numbers and opportunities" said that.
He was speaking to Sunday Times after the closure of the Nile Basin Development Forum in Kigali recently.
Nile Basin is made up with 10 countries, namely Burundi, DR Congo, Egypt, Ethiopia, Kenya, Rwanda, South Sudan, The Sudan, Tanzania and Uganda.
"For instance, if you build a dam for irrigation, that dam would irrigate 20,000 hectares but what about people who are not covered by those 20,000 hectares if their land is located somewhere else? In that case, the farmers can tap into ground water if it is available around that area.
He pointed out that ground water quality in the Nile Basin is generally ok and it can be used for irrigation, drinking, and for industrial water supply.
Vincent Kabalisa, head of water resources department at Rwanda's Ministry of Water and Forests told Sunday Times that Rwanda has large quantity of underground water and "it is strategic water that we often use when we have [water] problems, and such water is often of quality."
According to figures from the Rwanda Ministry of Water and Forests, the renewable water resources availability (in water bodies such as lakes and rivers as well as rain) per annum in Rwanda is 6.8 billion cubic metres (m3), while ground water recharge is estimated at 4.5 billion m3 per annum.
"In our programmes, we plan to use it [underground water] in increasing our capacity for drinking water because it is mostly purified water," Kabalisa noted.
"For instance, we are looking for ways such water can be supplied to people in Eastern Province of Rwanda so that they be able to use it," he said.
Dr. Elmusalami Yousif Fadlallah, Associate Professor in Ground water at Khartoum University in South Sudan said that there is heavy rainfall in Rwanda and Kenya, which increases the likelihood for ground water recharge, which is different from South Sudan as there is very limited groundwater recharge owing to minimum rainfall.
He said that groundwater is essential for the rural areas which are far from the Nile.
Kebede said that there is a need for collaboration between the Nile Basin countries to map the resources to have reliable, accurate and consistent figures on ground water because it is 'a hidden resource', not like surface water which can be seen easily and measured such as how much water is flowing and how much is recharging.
Comparative advantages of groundwater
Dr. Fadlallah said that ground water was very important and essential for rural areas such as helping farmers in crop production, and animal herders, while surface water supplies the main cities and helps generate power.
For Dr. Yilma Selelhi, Water Resources Engineer, Addis Ababa University, groundwater utilisation can be accessed by the population for use without much infrastructure demand.
He said that ground water can supplement surface water, noting that there was need to work on identifying ground water potentials and knowing the recharge quantities and working on enhancing such water recharge.
Talking about advantages of ground water, he said: "If you take similar volume of water from surface water and groundwater for irrigation, farmers who depend on ground water have proven to produce more crops and get more value compared to surface water."
Ground water use
According to the State of the Nile Report by the Nile Basin Initiative, ground water is an important resource, supporting the social and economic development of the Nile riparian countries and making an important contribution to water and food security in the region.
With the exception of Egypt, ground water from wells, springs, and boreholes is the main source of drinking water for rural communities in the basin.
In the Nile Equatorial Lakes Plateau and the Ethiopian Highlands, about 70 per cent of the rural population is dependent on ground water. This proportion rises to about 80 per cent in The Sudan and close to 100 per cent in South Sudan.
In Egypt, groundwater accounts for only about 13 per cent of total annual water requirements.
In addition to domestic use, ground water in the Nile region is also used for agricultural irrigation, livestock watering, and industrial processing.
What is needed to effectively use ground water
Kebede said that farmers need to have access to technology, digging and drilling; financing for farmers to buy pumps, but also market availability for farmers get buyers for their farm produce.
"Urbanisation, growing demands from urban centers will drive ground water development.