Risk-based operational water management for the Incomati River Basin


In heavily committed basins with many different water use(r)s located in different riparian countries strong inter-dependencies exist, whereby water allocation decisions have important economic, social, environmental and political consequences.

Decision making involve difficult tradeoffs, for which decision-support tools exist that are frequently based on optimizing an economic objective function subject to constraints representing, among other things, hydrological processes. Large variability of rainfall, both within and between years, leads to even larger variations in river flow and adds uncertainty to the water allocation equation.

Project duration

2008 to 2014


Research aim

The proposed research aims to assist water managers and stakeholders in identifying, implementing and continuously adjusting efficient allocation policies in a dynamic and uncertain hydrologic environment. Thereto, an innovative policy support system will be developed that integrates the physical, social and economical dimensions of the allocation problem while explicitly considering the hydrologic and climate uncertainties. This policy support system will improve the quality of information upon which managers can develop hedging strategies in order to reduce the risk exposure of the various water users. This policy support system will be developed and tested for one particular river basin, namely the Incomati river basin.

Project objectives

  • To improve our scientific understanding of the hydrology, ecology and economy of the Incomati river basin
  • To assess the sensitivity of the study area to exogenous climatic conditions such as sea surface temperature anomalies, and whether this can be used for flow forecasts
  • To develop optimal allocation policies and to provide operating advices for relevant Basin Water Authorities
  • To quantify the trade-offs and synergies between the different water uses and users in the river basin, and the economic gains and losses associated with water transfers
  • To develop and analyze policy instruments and dynamic planning and management strategies, including institutional adjustments such as compensation mechanisms.