Environmental experts say by the year 2100 there will be a serious problem of rainfall distribution in sub Saharan Africa which will cause low or poor crop production and drying of available water sources.
They say drip irrigation will be an advantage on reducing the cost of using a lot of water for irrigation.
Today, the scientists say, it is more important to use water resources wisely and intelligently as many farmers have turned to drip irrigation and are enjoying improved profitability by increasing crop yield.
However, many tea farmers in the Southern Highlands of Tanzania, especially in Mufindi, Njombe and Rungwe have enjoyed significant water through using drip irrigation.
Drip irrigation is more important to farmers because it is more targeted, intelligent application of water, fertilizer, and chemicals that when used properly can provide great benefits.
The Tea Research Institute of Tanzania (TRIT)’s Pogramme Leader of Crop Water Management, Benjamin Mtaki, says that his institution has come up with such technology and has established a crop water management programme on the efficiency of using drip irrigation in tea production to large and small- holder tea growers.
"After seven years of investigation the institute came up with a new technology of irrigating tea both in large scale and smallholder farms," he says.
"Tea drip irrigation enables farmers to have double production of green leaves as compared to the traditional sprinkler irrigation that has been used before. It enables efficient utilisation of water to adapt to climate change and poor distribution of rainfall," he explains.
That type of irrigation is the artificial application of water to the land. In order to become of economic value there are important things to be considered.
These include the frequency and duration of the dry seasons, the age and vigour of tea, the depth, type and fertility of the soil and the availability of water suitable for irrigation.
"It is used to assist in the growing of agricultural crops, maintenance of landscapes and revegetation of disturbed soils in dry areas and during periods of inadequate rainfall. Additionally, irrigation also has a few other uses in crop production, which include protecting plants against frost, suppressing weed and helping in preventing soil consolidation," Mtaki says.
"In contrast, agriculture that relies only on direct rainfall is referred to as rain-fed or dry land. Irrigation systems are also used for dust suppression and disposal of sewage.
Mtaki says several important new irrigation innovations have been developed and commercialised in the past few decades. They include automated canal and piped water delivery systems, laser land levelling for surface irrigation applications, set and automated sprinkle irrigation, micro-irrigation and sub-surface drip systems, just to mention few.
"With these new technologies, it is technically practical to uniformly irrigate a field so all areas receive approximately 90 percent or more of the average amount of applied water per unit area," he explains.
Furthermore, with subsurface drip irrigation and accurate scheduling almost all of the water applied to the plants is transpired (the evaporation component of the applied water evapotranspiration is minimised).
Mtaki says that drip irrigation is an efficient method of watering plants. Drop by drop, the water flows through a special pipe to very small outlets called emitters watering the soil around the plant roots – hence the name “drip irrigation”.
It also said that water is applied close to the plant so that only the soil immediately surrounding the plant receives a very limited volume of it meaning that no water is wasted as runoff or lost by moving down through the soil too quickly for the roots to absorb it.
Compared to the water sprinkler systems or to furrow-irrigation methods, drip irrigation can achieve 90-95 percent water efficiency.
The technology has been further simplified and requires low water pressure to operate. The drip pipes are very flexible and can be modified to suit different lengths of rows or plot sizes.
Drip irrigation has enabled farmers, nurserymen, and landscapers to conserve water for decades. This is primarily because, in contrast to gravity or sprinkler irrigation, drip irrigation technology applies water slowly and directly to the targeted plant's root zone.
In addition, drip irrigation technology has extremely high application uniformity, even when pressures vary from hilly terrain or long lengths of run, or where planted areas are oddly shaped.
John Joseph, a farmer in Njombe, says that at the time when he starts drip irrigation technology he finds that the amount of water used is very minimal.
“By applying water only where and when it is needed, with less runoff and less evaporation from leaves and soil, the uniform application of water from drip irrigation systems can achieve high water savings,” he says.
“Drip irrigation has reduced pest problems and weed growth," he adds.