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非洲南部的小農耕作有著非常豐富的傳統。在這種農耕體系中水的利用是具可持續性的，其中可能包括雨水和地下水澆灌，小型水壩、淺井、低成本的幫浦抽水器以及節水保濕的農耕方法。透過仔細的考慮，將傳統的節水技術和現代的有效方法相結合，這可能會有助於平衡乾旱地區農業的需要，和滿足發展中世界對水的需求。
在非洲南部，很多傳統的灌溉方法過去一直沒有被官方的灌溉工程所採用，如聯合國糧農組織的計畫，這種情況直到最近才稍有改變。據水利專家珊德拉‧波思岱爾說，雖然他們現在有了較深的認識，但非洲的小規模灌溉方法，幾乎沒有投資可信度，無法拓展實行，也無法對大型公共灌溉計畫提供其他形式的支援。波思岱爾在【最後的綠洲】中便寫道：「結果，非洲小規模灌溉的潛力就一直受到壓制，得不到發展，糧食生產也一直得不到安全保障。」（請見資料來源）
年平均雨量為100毫米或低於此數目的地區，就採用「逕流式農耕」（runoff agriculture）。雨量大的時候，人們收集雨水，導入儲水槽，以便在乾旱季節仍有水可用。
坦桑尼亞的Sonjo用矮灌木做的小水壩引導水流，灌溉吉力馬紮羅山的斜坡，水壩最高至3米。這種小水壩很容易遭洪水毀壞，且洪水會沖走水壩後方的許多沈積物，因此這個特徵能夠提昇整體系統的可持續性。和大型水壩不一樣的是，矮灌木水壩仍允許水流通過，因此減少了對下游生態的破壞。這種水壩是利用當地的材料和由當地的勞力所建造而成，所以重新建造這些水壩通常花費並不大。
另一個傳統方法是，在坡度較緩的地面上，沿著等高線，堆起長長的石岸，以減緩應流水的速度，和擴大水流流經的範圍。布基納法索（非洲國家）的Yatenga地區發展出這種方法，現在該國400個村莊中，有8000多公頃農田都採用這個方法。肯亞和尼日也採用此法。據【缺水世界的解決方法】一文，此舉將農作物產量提高了約50%。
辛巴威的Dambo耕種模式是自然水源可持續利用的典範。Dambo所利用的土地面積非常小（通常還不到半公頃），是季節性地被水淹沒的山谷，並且都是位於盆地的排水口，水流過這裏進入更大的水渠。從較高處和溝渠收集而來的水，可供這些山谷裏生長的植物利用。倘若旱季延長了，Dambo可以保留水分，在某些旱災時期裡，這裡也是唯一生產玉蜀黍的農場。
與非洲的大型灌溉計劃恰恰相反的是，經驗說明小規模灌溉在多數情況下獲得良好反應，並且它還有很大的未開發的擴展潛力，包括在公共及私人投資兩方面。困難就在於很少有政府只為了這些工程的效率很低，而會願意放棄對大型專案的投資。大規模體系更容易被中央政府控制，因此，才會吸引非洲國家那些保護自己地位的城市官僚主義者。(註)
註：本段落出自於『非洲水資源利用要點：需求管理，節約以及效率』書，為
傑弗瑞‧斯戴爾 所著
版權歸屬 國際河網IRN，環境資訊協會（陶俊 譯，李傑、李瑞玉 審校）
中英對照全文：http://e-info.org.tw/issue/water/2001/issue-water-irn01091001.htm
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Southern Africa has a rich tradition in small-holder farming. Water consumption in such systems is usually sustainable. Such systems may include rain- and groundwater harvesting, microdams, shallow wells, low-cost pumps, and moisture-conserving agricultural practices. Careful consideration of traditional water-saving techniques combined with effective modem methods may help to balance the needs of dryland agriculture and help to meet the developing world's water demand.
Up until recently, many of these traditional irrigation methods were excluded from official irrigation programmes in Southern Africa, such as UN Food and Agricultural programmes. According to water expert Sandra Postel, although they are now getting greater recognition, Africa's small-scale irrigation methods are rarely offered the investment credits, extension services and other forms of support given to large public irrigation schemes. "As a result, small-scale irrigation's potential in Africa remains constrained and underdeveloped, and food production remains less secure," Postel writes in Last Oasis (see Resources).
Runoff agriculture has been used in regions where the average yearly rainfall is 100mm or less. During high rainfall, rain-water is collected and diverted into storage tanks and used throughout the dry season.
The Sonjo of Tanzania divert water with small brushwood dams, up to three metres high, to irrigate the slopes of Mount Kilimanjaro. Small dams of this type are easily destroyed by floods, a feature which can enhance the sustainability of the overall system as the floods then wash away most of the sediments behind the dams. Unlike large darns, brushwood dams still permit water to flow through, thereby decreasing ecological damage downstream. Because the darns are built with local materials and labour, rebuilding them is usually not a major expense.
Another traditional method involves placing long lines of stones along the contours of gently sloping ground to slow runoff and spread the water across a wider area. Developed in the Yatenga region of Burkina Faso, this method is now being used on over 8,000 hectares in 400 villages throughout the country. It is also used in Kenya and Niger. This practice has increased crop production by about 50 percent, according to Solutions for a Water-Short World.
Dambo farming in Zimbabwe is a classic example of the sustainable uses of a natural water resource. Dambos are small (usually less than half a hectare), seasonally waterlogged valleys at the head of a drainage basin where water makes its way to larger channels. Water collected from the runoff of higher ground and channels support the many gardens growing in these valleys. Dambos can maintain water during prolonged droughts, and have been the only farms to produce maize during some droughts.
In contrast to large-scale irrigation schemes in Africa, small-scale irrigation has had largely positive experiences and this offers considerable untapped potential for expansion involving both public and private investment. The difficulty is... that few governments have been willing to forego investment in large-scale schemes simply because they are inefficient. Large-scale systems are more amenable to central government control and, therefore for attractive to the entrenched urban bureaucracies of many African states. -- GEOFFREY STILES, "DEMAND-SIDE MANAGEMENT, CONSERVATION AND EFFICIENCY IN THE USE OF AFRICA'S WATER RESOURCES"
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