One Strategy, Three Sectors, Many Benefits: Multipurpose Reservoirs as Drivers for Sustainable Development

  • 2015/09/02     Stockholm, Sweden

    Outcomes of the joint session at World Water Week 2015 organized by UNU-FLORES, the International Hydropower Association (IHA) and the United Nations Development Programme (UNDP)


    The proposed Sustainable Development Goals (SDGs) aim to achieve food security, ensure the availability of water and ensure access to energy for all, among other things. To achieve these goals, by 2030 we will need 35% more food, 40% more water and 50% more energy according to the 2014 World Water Development Report. This will result in high demand of water for many different uses and by many different users. Meeting this demand sustainably will require integrated water management options that can address the numerous users and uses of water in all of these sectors, strategies that apply a Nexus Approach.

    One feasible opportunity to put such an approach into practice is given with multipurpose reservoirs, providing both water and energy services. When developed and maintained in an integrated manner, multipurpose reservoirs can deliver hydropower for sustainable energy while simultaneously securing the supply of water for human consumption, agriculture, industry, navigation and the management of floods and droughts. At World Water Week 2015 in Stockholm, UNU-FLORES, the International Hydropower Association (IHA) and the United Nations Development Programme (UNDP) convened a session to discuss the possibilities and limitations of utilizing multipurpose reservoirs for integrated water management and for sustainable development.


    Hydropower is a growing industry, particularly in emerging markets “where it offers not only clean energy, but also water services, energy security and facilitates regional cooperation and economic development,” Tracy Lane, Director of Hydropower Development at IHA, outlined in her presentation. In addition to electricity generation, she pointed out that hydropower can provide other developmental benefits, such as flood and drought protection, irrigation and aquaculture potential, water storage and supply, sanitation, and downstream flow regulation. Recently, in light of the evolution of the renewable energy market, hydropower has been awarded significant attention due to its ability to store energy. The technology used in hydropower offers a considerable degree of flexibility, storing potential energy for later use.


    Lane emphasized that this ‘flexibility also allows hydropower to compensate for variable renewable energy output, making it an important asset for enabling deployment of other renewable energy technology such as solar and wind.’ Finally, hydropower can offer important services in the areas of climate change resilience, adaptation and mitigation.

    All these functionalities of multipurpose hydropower reservoirs make them particularly interesting as drivers of sustainable development. Nevertheless, according to statistics from ICOLD, 74% of all dams worldwide are predominantly single-purpose dams, meaning they were developed and are managed for the purpose of providing only one of the services outlined above – mainly irrigation. Identifying development and management strategies that consider other water uses and users as well as environmental, social and economic implications is essential to maximize the benefits of water storage infrastructure and hydropower. ‘There are hundreds of mathematical models available to calculate how to best operate reservoirs, but most of those models focus on one user/use as the main variable and treat other users/uses as constraints,’ UNU-FLORES Director Reza Ardakanian pointed out during the session. One aspect is given a privileged role in these models, instead of looking at all aspects equally. ‘Successfully managing hydropower reservoirs to drive sustainable development will require new or linked models, able to consider water uses in an equitable way across sectors, promoting synergies and minimizing trade-offs – in short, a Nexus Approach’.

    Panelists (from left to right): Reza Ardakanian (UNU-FLORES), Lin Chuxue (China Three Gorges Corporation), Tracy Lane (IHA), William Rex (World Bank), Lifeng Li (WWF) and Joakim Harlin (UNDP)

    Panelists (from left to right): Reza Ardakanian (UNU-FLORES), Lin Chuxue (China Three Gorges Corporation), Tracy Lane (IHA), William Rex (World Bank), Lifeng Li (WWF) and Joakim Harlin (UNDP)

    Multipurpose reservoirs, developed and managed in this manner, can be an effective tool for achieving many of the targets outlined in the UN Sustainable Development Goals. To elaborate on the potential and limitations this type of infrastructure project offers, the session continued with a panel discussion providing various perspectives on the issue and drawing on specific examples. The Three Gorges Dam in China served as useful example since ‘all dams built by the corporation are multipurpose,’ stressed Lin Chuxue from the China Three Gorges Corporation. ‘The #1 purpose of the Three Gorges Dam is flood and drought control, #2 electricity generation and #3 improving the navigability of the river’. The case of hydropower development in Mozambique provided insights into some specific opportunities and challenges of a developing country with high hydropower potential but generally weakly developed water and energy infrastructure.

    While multipurpose reservoirs are clearly an important water management option, the development and maintenance processes can be optimized further to ensure sharing of benefits across uses and users. For example, many reservoir development projects involve representatives from the social and environmental sectors as well as the economic, but often too late in the process to truly maximize benefits for all. Li Lifeng, Freshwater Director at WWF, pointed out that environmental considerations should happen at the beginning of the process. The location of a project should not be chosen based on the electricity generating potential alone, but also on the impact on the ecosystem and conservation efforts.

    www15_talks_01-1-300x252 Another important conclusion of the discussion was that there needs to be more research on the economics of multipurpose dams. There is research on the ecosystems services, on the social benefits and challenges, on the financial returns, the flood protection and the navigation, but ‘the ability to start pulling these together is what will enable societies and governments to work out what the real trade-offs are,’ argued William Rex, Global Lead for Hydropower and Dams at the World Bank. ‘We need a science of the economics of trade-offs’.

    Joakim Harlin, Senior Water Adviser for UNDP and moderator of the panel summarized by emphasizing that multipurpose reservoirs pose considerable opportunities for achieving the SDGs. However, this will require that the development and maintenance of reservoirs takes possibilities for benefit sharing into consideration. Applying a Nexus Approach to the development and management of hydropower reservoirs will be crucial in addressing these key challenges.

    Besides convening the aforementioned session, UNU-FLORES represented the United Nations University in the World Water Week Exhibition. Water for Development is a common theme across many Institutes in the UN University. Under the slogan #UNU4Water, Institutes and programmes joined forces to develop a campaign that showcased the various projects and publications focusing on this theme. One of the main institutes working on water, UNU-FLORES presented these projects and publications to the participants at World Water Week 2015.

    For more information on the strategic opportunities for hydropower in Mozambique see UNU-FLORES Working Paper No. 4.