Hydrological modelling to assist water management in the Usangu wetlands, Tanzania
- 1 March 2008
- journal article
- research article
- Published by Taylor & Francis in International Journal of River Basin Management
- Vol. 6 (1), 51-61
- https://doi.org/10.1080/15715124.2008.9635337
Abstract
The Usangu wetlands, containing the Ihefu swamp, are one of the most valuable inland wetlands in Tanzania. Over the last decade, outflow from the swamp has ceased for extended periods in the dry season. This has had severe consequences for downstream ecosystems, including the Ruaha National Park. Results from a simple hydrological model developed for the Ihefu swamp indicate that, between 1958 and 2004, dry season inflows declined by approximately 60% and the dry season area of the swamp decreased by approximately 40% (i.e. from 160 km2 to 93 km2). The model also shows that to maintain minimum downstream environmental flows requires a minimum inflow of 7 m3s‐1, which is approximately 65% greater than occurs currently. There is significant potential for improving water use efficiency. However, given the socio‐economic importance of current levels of water withdrawal, this inflow may be difficult to achieve. Consequently consideration needs to be given to other options, including upstream storage and water management within the wetland itself. This paper highlights that a simple model supplying relatively low‐confidence, but indicative, results can provide a useful basis for contemplating water management options.Keywords
This publication has 14 references indexed in Scilit:
- Towards an ecohydrology-based restoration of the Usangu wetlands and the Great Ruaha River, TanzaniaWetlands Ecology and Management, 2006
- Dynamics of Usangu plains wetlands: Use of remote sensing and GIS as management decision toolsPhysics and Chemistry of the Earth, Parts A/B/C, 2006
- Environmental flows allocation in river basins: Exploring allocation challenges and options in the Great Ruaha River catchment in TanzaniaPhysics and Chemistry of the Earth, Parts A/B/C, 2005
- Entrenched views or insufficient science?Agricultural Water Management, 2004
- Mitigation of negative ecological and socio-economic impacts of the Diama dam on the Senegal River Delta wetland (Mauritania), using a model based decision support systemHydrology and Earth System Sciences, 2003
- Evaporation characteristics of wetlands: experience from a wetgrassland and a reedbed using eddy correlation measurementsHydrology and Earth System Sciences, 2003
- A desktop model used to provide an initial estimate of the ecological instream flow requirements of rivers in South AfricaJournal of Hydrology, 2003
- DITCH: a model to simulate field conditions in response to ditch levels managed for environmental aimsAgriculture, Ecosystems & Environment, 2000
- Modelling ditch water levels on the pevensey levels wetland, a Lowland wet grassland wetland in East Sussex, UKPhysics and Chemistry of the Earth, Part B: Hydrology, Oceans and Atmosphere, 2000
- Estimating evaporation and surface resistance from a wet grasslandPhysics and Chemistry of the Earth, Part B: Hydrology, Oceans and Atmosphere, 2000