Waterwise is a tool to prioritise land and water management options in large river basins. The prioritisation is based on an integrated model for hydrology, crop production and hydropower, coupled to a mathematical optimisation algorithm.
In many regions in the world, both land and water resources are under increasing stress. It is against this backdrop that scientists at Wageningen University & Research developed a novel approach to assess where and how food production can be increased and whether food self-sufficiency can be realistically achieved or maintained for basins like the Nile Basin and the Ganges-Brahmaputra Basin. With WaterWise, a hydro-economic model developed by Wageningen University & Research that integrates yields from both rainfed and irrigated agriculture in combination with the yield from hydropower, they explored various food self-sufficiency and regional cooperation scenarios for these Basins.
The scenarios included the possibility for: national food self-sufficiency, individual states or upstream countries developing their irrigated agriculture potential to the maximum, and regional cooperation where food and hydropower are produced where it is most cost effective. The model consists of three modules on water flows, crop production and hydropower and an optimisation routine to select the most suitable land use and hydropower options, given a certain level of investment. The latest data on soils, land use and crop production, including the costs and benefits of each crop production type, were used to calibrate and validate the model.
Photo by Marc Ryckaert (MJJR)
The modelling system ‘Waterwise’ thereby attempts to provide an alternative to ‘conventional’ simulation models largely based on trial and error. Instead of (yet another) simulation system it provides a framework for answering ‘inverse’ policy questions. Simulation models can be used for answering questions of the type: ‘What is the effect of a water harvesting structure on downstream flow?’. The inverse question would be: ‘Where should I construct water harvesting structure to get an optimum production given available water resources?’. Waterwise can answer such questions and at the same take various types of preferences into account.
A description of the model is given in Waterwise (doc file); the source code is available in Waterwise_code (text file).