The Herald, 6 March, 1980
AT LEAST three million hectares of Zimbabwe’s land surface can be put under crops irrigated from groundwater (water extracted from springs, dug wells, boreholes and all other kinds of water point.)
This area is far in excess of that under groundwater irrigation. It also greatly exceeds the total area irrigable by surface water from rivers.
For almost 50 years, it has been a widely-held belief in Zimbabwe that groundwater is difficult to find.
This belief is incorrect in most places throughout Zimbabwe.
In fact, usually it is much more difficult not to find groundwater than it is to find it.
The origins of the belief are irrelevant here, but the belief itself has an inhibiting effect on the extension of the area under groundwater irrigation for the following reasons:
First, the available data were not analysed until 1977. Not until then was it possible to identify and locate the regions suitable for irrigation from high-yield wells and low-yield wells. The former, desired by the large-scale farmer will irrigate at least 200 000 hectares. The latter, suited to the small-scale farmer will irrigate at least three million hectares.
Second, the extensive use of low-yielding wells for crop irrigation by small-scale farmers appears not to have been considered.
Crop irrigation from groundwater is free from those limitations to the extension of the area of and irrigated by surface water. It has other more important advantages also. It offers to Zimbabwe its greatest single opportunity for:
increasing social stability in the country;
suitably resettling refugees, ex-soldiers and others;
greatly increasing the value of Zimbabwe’s agricultural production;
providing great employment opportunities.
Based upon a long experience of rural socio-economic development, the writer, sees no better solution to Zimbabwe’s post-election and population problems than the properly planned considerable extension of the area under crops irrigated from groundwater.
The potential economic rewards can be great. The effect on social stability both within Zimbabwe and its neighbouring countries can also be great.
The expenditure of Z$500 000 to initiate the achievement of these goals is ridiculously small, but it can achieve the purpose, if the work is done under suitable conditions.
Zimbabwe has a choice. Will it choose to increase the benefits obtainable by increased crop irrigation from groundwater?
Or, will it choose to remain content with its present situation?
LESSONS FOR TODAY
This definition from an online source gives a 21st Century understanding of underground irrigation: “ . . . a method that delivers water to gardens and lawns through buried hoses or pipes. The different types of underground irrigation are: irrigation hose, drip irrigation and sprinkler systems. Depending on the size of the area that needs an irrigation system and the level of expertise required to install it, many people will hire irrigation companies instead of doing the work themselves.”
Even if Zimbabwe had normal rainfall patterns, underground irrigation would still be one of the most viable options to ensure food security and exportation.
The availability of cutting technology gives room for better research on the irrigation method so that farmers do not underestimate its importance in agri-business.
The writer Dr Donald Gear, had spent 33 years, including 22 with the United Nations, and three in Rhodesia) in 18 developing countries in Africa, the Middle East, Asia and Australasia. He worked on the planning, investigation and development of water resources, especially groundwater and related disciplines.