Optimal resources allocation in the Upper Blue Nile basin

2018 Fall Cyberseminar Series

Mariam Allam / University of Massachusetts Amherst

Talk Description

The Nile basin is under stress due to rapid population growth rates, inefficient allocation of resources, impacts of climate change, and conflicts between riparian countries sharing the basin waters. This research develops a framework for optimal allocation of land and water resources to agriculture and hydropower production in the upper Blue Nile (UBN) basin, which contributes about 60 percent of the Nile river flow. The framework consists of three optimization models that aim to: (a) provide accurate estimates of the basin water budget components, (b) allocate land and water resources optimally to rain-fed, and irrigated agriculture, and (c) allocate water to agriculture and hydropower production, and investigate trade-offs between them.

Maps of suitable lands are delineated and incorporated into a land-water allocation model allowing for enhancing soils from one suitability class to another to increase agricultural productivity. The model allocates land to rain-fed agriculture while maximizing the total net economic benefits. This framework is extended to incorporate irrigated agriculture in the basin where eleven proposed irrigation projects are screened, and only three of them were found economically attractive. This optimal agricultural expansion is expected to reduce the basin flow by 7.6 cubic kilometers which will impact the downstream countries.

Cooperation scenarios that limit the magnitude of this reduction are studied and their impact on the net economic benefit is quantified. The optimization framework is expanded further to include hydropower production from the Grand Ethiopian Renaissance dam (GERD). Optimal operation rules are identified to maximize annual hydropower generation from the dam while achieving a relatively uniform monthly production rate. Trade-offs between agricultural expansion and hydropower generation are analyzed defining scenarios for cooperation that would achieve win-win outcomes for all riparian countries of the basin.

CUAHSI's 2018 Fall Cyberseminar Series: Major Challenges in Key River Basins Around the World

Hosted by Katherine Schlef, CUAHSI

Water management of major transboundary river basins is fascinating in its complexity and is also increasingly challenged by change in both hydro-climatology and human populations. For example, the climatology in large transboundary river basins may be influenced by monsoons, mesoscale convective systems, hurricanes, or orthographic rainfall. The hydrology can be similarly complex, ranging from high-elevation glacier- or snowmelt-fed catchments to completely urban landscapes to low-lying flatlands or arid plains with substantial groundwater interactions. Furthermore, human use of water for agricultural, municipal and industrial, and hydropower generation purposes alters the natural water cycle and can become contentious when water crosses geopolitical boundaries and as demand for water increases. In this seminar series, you will hear perspectives from a diverse set of emerging researchers regarding the challenges and possible solutions facing major transboundary river basins in the world, such as the Indus River Basin in Pakistan, the American and Sacramento River Basins in California, the Ohio River Basin in the United States Midwest, and the Nile River Basin in Ethiopia. You will gain an increased appreciation for the complexity of water management in such basins and will be inspired by the innovative and novel methods being used to solve the many challenges they face.