The results of a two-year study to look at the flow of water and the health of the Mbarali River in Mbeya Region have shown that the water is decreasing and this is due to the increase in population and the need for water use to increase along with the destruction of the river's water sources.
That is stated by Prof. Japhet Kashaigili from the Sokoine University of Agriculture (SUA) who is the Principal Researcher of the two-year project on the Sustainable Catchment Management through Enhanced Environmental Flows Assessment and Implementation for the protection of the Western Indian Ocean from land-based sources and activities in Tanzania (EFLOWS) while presenting the results of the study to the stakeholders of the Mbarali River in the district in Mbeya Region.
"What we have seen in the research is that the amount of water in the river has continued to decrease, the need for water is increasing but also climate change has significantly affected the dispersion of water and rain in these areas and thus led to a decrease in water in the river and its negative effects are seen in the ecology of the river ecosystems especially during dry season. We have seen the presence of large-scale use of water without water use permits by using water pumps, and large production of sediments during the rains due to human activities in the catchment areas in the mountains and in the fields," said Prof. Kashaigili
He added" The human activities that take place in Mbarali River catchment in the sense of housing, agriculture, livestock grazing, brick making at water sources and in the river, crop cultivation, fire and other anthropogenic activities have contributed significantly to the decline in water flows in the river, but mostly, the river water abstractions is responsible to the observed negative effects".
Prof. Kashaigili further noted that the challenge of the large use of water has led the river to dry up completely in the lower areas of the river (downstream) while the upper areas of the river and when you reach the middle you find a lot of water flowing that does not reach the end, it ends up on along the way due to people diverting it and drawing it for their various activities, especially agriculture that doesn’t follow the crop water requirements with low water use efficiency.
"This means that the Mbarali River does not contribute anything to the Great Ruaha River especially during the dry season in the conservation areas and this means that the ecology of the river and its sustainability has been affected and thus hampering achieving the global sustainable development goals and the national goals of conservation and protection of the river biodiversity" explained the Principal Researcher Prof. Kashaigili
This globally renowned researcher in water and environment has said that in addition to the research to provide the results to the important stakeholders, they have also identified ways and strategies to do which, if done, will help reduce the effects that have occurred and help restore the health of the river and the flow of water on the Mbarali River and others in the country because the challenges are similar.
He said one of the strategies was to restore natural vegetation to all the water sources, the affected river banks, where the project has initially helped to establish two large nurseries of water-friendly trees in the district of Wanging'ombe in Njombe Region and Mbarali in Mbeya Region by using local knowledge and succeeded in planting more than forty five thousand (45,000) trees on the sources and banks of rivers as well as starting beekeeping to increase the income of the water user associations that manage watersheds as well as increase conservation.
On his part, an expert in aquatic sciences and micro-invertebrates from the Open University of Tanzania, Mr. Sherald Mkama who was monitoring the health of the river and water safety through the project has said that the results have shown that the water flowing in the river is still safe because after conducting research they have found organisms that cannot live in water that is not safe.
"The small creatures that live in the water together with the fish have a great ability to signal the quality of the water in the area and that is why along with other researchers they take water samples and measure them, but the method of looking at the micro-inverts is the most important because they stay for a long time in the area that is better than measuring the water because you can go to fetch water and find that it is better for that time only, but the creatures that live in the water do not flow with water, are always there all the time" explained Mkama.
The researcher has asked the authorities in charge of water to ensure that there is good management especially in the areas where they draw a lot of water from the Igomelo Irrigation scheme where they use pesticides and in the end part of the water returns to the river containing toxic agents, if they do not consider the safe use of pesticides, may in the end kill the organisms in the river and also affect the community that depends on the water of the river for domestic use.
Dr. Emmanuel Mwainunu from the Tanzania Forest Research Institute TAFORI talking about his research area.
The researcher who was looking at the plants growing along rivers and water sources, Dr. Emmanuel Mwainunu from the Tanzania Forestry Research Institute (TAFORI) has said that these plants are important because they help with the maintenance of the river health by absorbing fertilizer and making it flow slowly instead of fast as well as preventing erosion of riverbanks.
"When we look at the condition of vegetation on rivers and the health of the river, we use grades A to F, so when we say the condition of a certain zone is A, it means there is no damage in that area, but if grade B means the area has started to experience initial effects but they have not started to cause harm, and if it goes down to grade D, it means the impact is severe and if it reaches grade F, it means that the area is very damaged, meaning the impact is very big and its effects are so big that it is not easy to repair in normal conditions. Our assessment has shown that there are several changes that have resulted from agricultural and livestock activities, but basically its damage to the vegetation of the river banks is not very great and leads to getting grade B, however, efforts must be made to stop this challenge from continuing" explained Dr. Immanuel.
He has said that they have found plants such as sandalwood (Msandali) which are plants with many uses such as the production of perfumes as well as other water-friendly plants but it is possible to disappear because communities are doing various activities along the river and affecting it, so deliberate efforts should be taken by the river basin management authorities to save the river and keep it intact.
This research project is implemented by the Sokoine University of Agriculture (SUA) in collaboration with the National Environment Management Council (NEMC) and implemented in the Rufiji River Basin within the Mbarali River catchment in collaboration with the Rufiji Basin Water Board, water user associations, Tanzania Forest Services Agency (TFS), Mbarali and Wanging’ombe Districts and communities, with funding from the United Nations Environment Program, UNEP, through contributions from ten contracting parties of the Nairobi Convention whereas for Tanzania it is through the Office of the Vice President, Division of Environment, in implementing the Strategic Action Plan for the Western Indian Ocean under the coordination of the Secretariat of the Nairobi Convention.