The main areas where water can be saved and released for drainage from Usangu to feed the Ruaha River in the Park during the low flow period are presented for August 4, 2022. The locations of the focus areas for August 2022 is illustrated in the first map. The spill at Madibira has not been included yet.
A pick from obvious sources of spill is summarised in the images below.
Four Focus Areas in the Ruaha River Subbasin and Three Areas in the Mbarali Subbasin show irrigation, spill and riverine evapotranspiration.
A more detailed presentation for the Igomelo small scale irrigation scheme which diverts during the extreme low flow in the Mbarali some few hundred liters per second is provided below.
Not all irrigated farms at Igomelo SSI scheme are visible due to clouds and related shades as can be seen on the image above. The Igomelo farmers are entitled to abstract 17280 m3 in the period from May to November according to the Rufiji Basin’s water abstraction rate table. With 24 hour abstraction per day this correspnds with 1 liter per second for the 320 ha scheme. Obviously the abstraction with the existing infrastructure will exceed the planned abstraction and the current practice should be reconsidered in the light of the growing water stress in the Mbarali River during the low flow period. The images shows riverine “natural losses” along the various tributaries including along the Mbarali River channel in the center. In the hilly environment of Igawa limited spill takes place. It is doubtful if any significant amount of water can be saved from Igomelo.
