Hydrologic budget for the great Ruaha river basin.

For all water resources and environmental management decisions, accurate calculation of the hydrologic budget is very important. Although many of the components involved are very difficult to measure, consideration of all of them is essential. In this research, attempt has been made to complete the hydrologic budget for the Utengule Swamp of the Great Ruaha River Basin (which forms part of the Rufuji Basin of Tanzania of total catchment area of about 178,000 km2) by determining the amount of water loss through evaporation for the period of 32 years (i.e. 1957-1988). Morton's Complementary Relationship Model was also used to estimate the evaporation of the swamp for a period of 16 years (i.e. 1977-1992). To ascertain the suitability of this model to the swamp, its results were compared with the results of the Proposed Water Balance Model developed for swamp. It was found out that the Model is suitable for this Utengule Swamp within 8.8% tolerance for the duration that was common to both periods (i.e. 1977-1988).