As is custom, Ntimbale Dam in the North East District on Monday 16th February released yet another environmental flow of water. The activity will last for a period of 9 days. Completed in 2007, the dam, which is located a stones throw away from Masingwaneng village, supplies a total of 43 villages with water.
It is international practice for water to be released from dams to the environment in order not to disturb the ecological system. Among others, Botswana is guided by the SADC Protocol on Shared Water Courses.The tradition comes from the understanding that, before a dam is built, the environment, including the riparian communities as well as the vegetation downstream, will have had unrestrained access to flowing water from the river.
The construction of a dam, it is argued, has the effect of reducing the amount of free-flowing water downstream hence the regular releases as compensation for the disrupted free-flow of water. According to the Acting Water Resources Manager, Moeti Matswiri at Water Utilities Corporation, the exercise is not symbolic. “The purpose of this is to ensure that life down-stream is not hampered. It also keeps the water table at a normal level.
We are not just doing this. A study was conducted on the basis of which we decided when and how much water we should release as well as the conditions that should guide our actions,” he said at a press briefing at the Ntimbale water treatment centre.
According to Matswiri, the release is supposed to be conducted twice annually: once in the month of February and once in the month of November. One of the conditions for the releases is that there should be enough water in the dam. The dam stands at 95% of its full capacity currently. Matswiri revealed that, in the event there have been low rains and the water level in the dam is low, no releases are done.
“In a dry rainy season, the environment will have not lost any water to the dam and hence no release was effected last year. This is because, due to the low rains between October and November, inflow was very low. “During dry spells, priority is given to the people and no water is released to the environment,” explained Matswiri.