Restoring the perennial Great Ruaha River using ecohydrology, engineering and governance methods in Tanzania

The hydrological model of the Usangu wetlands was further developed and verified, and then used to justify the construction of a low-level V-notch weir at the outlet of the Usangu wetlands; by slowing down the outflow from the wetlands, this construction would reduce the period of zero flow in the GRR during the dry season by one to two months. Additional ecohydrological solutions based on the improvement of water governance upstream of the Usangu wetlands, such as controlling rice and horticultural irrigation activities along the length of the GRR, should be integrated with this engineering solution; this would meet the hydrological needs of the water users all along the GRR.