Improving the governance of the floodplain in over-built river basins (SGP-HW 091)


Project information

Guilherme Fernandes Marques, Associate Professor, Universidade do Rio Grande do Sul (UFRGS)
Campus do Vale da UFRGS - IPH, Av. Bento Gonçalves, 9500 - Agronomia, Porto Alegre - RS, 91501-970, Brazil.
Contact: Phone: (+55) 31 99795-5184, E-mail:
July 2019 - 2022. USD 199,827.60
Brazil, Canada, Chile

Executive summary Results Outreach Investigators Students

Executive Summary

There is growing consensus worldwide that in hydropower-dominated river basins, the allocation of water can no longer be only driven by the demand for energy; rather a balance must be found between hydropower and the other uses including the environment and the need to sustain ecosystems. However, because water re-allocation has technical, economic and socio-political dimensions, it is a complex governance issue which lends itself to trans-disciplinary analytical framework. The uncertainty regarding global changes intensifies this complexity since it will affect both supply (water availability) and the various water demands in the river basin.

The overarching goal of this project is to improve the governance of the floodplain in over-built, over-committed river basins where the livelihood of riverine communities is at risk following the degradation of ecosystems and fragmented institutions. To achieve this goal, the project will tackle the following scientific challenges:

Understanding ecological effects on large wetlands and floodplains downstream of hydropower plants given their importance as biodiversity hotspots providers of a large number of ecological services such as fish reproduction, wildlife preservation and flood control;

Integrating decisions on ecosystem services protection and recovery with water allocation for energy and other competing demands, given it requires a well-structured approach and a strong interdisciplinary cooperation between academic partners, water managers and stakeholders;

Clear understanding of governance options which is necessary to bridge the knowing - doing gap and to support the required efforts in stakeholder involvement and capacity building to secure long-term intellectual support of science-based IWRM in the region.

Without transparent information about these issues, negotiation is contentious, and agreement is unlikely. As result, environmental demands remain unmet, ecosystem services end up compromised and the governance system will likely fail to adapt to future changing conditions and to provide reliable services to human wellbeing.

The methods and results of our project will allow:

Improved stakeholders’ awareness about the need to adapt to future changing conditions when ecosystem services are restored and maintained; Identification of improved operating rules to adapt to future conditions that reduce the trade-offs to other demands (water and energy); Calculation of the cost of the adaptation and proposing different institutional arrangements to share costs and benefits of adaptation, fostering collaboration and facilitating implementation of the desired adaptation plan. In this project, this will be accomplished with stakeholders’ discussion and interaction.

Finally, the collaboration between four institutions across Brazil, Chile and Canada, involving academic professionals, water managers and stakeholders will also contribute to consolidate a decision-making process that is both adaptive, science-based and participatory. The project will also strengthen institutional and professional liaisons for future application of scientific findings, new research ideas and real-world problem solving.


Keywords: ecosystem services, fisheries, fish production, dams.
The research team is working to improve the governance of the floodplain in over-built, over-committed river basins where the livelihood of riverine communities is at risk following the degradation of ecosystems and fragmented institutions. Some findings to date:
Professional fishing is facing a decline in the region, from 1,200 registered fishermen 10 years ago, to 700 registered 3 years ago and 384 registered currently. Those figures are still approximate estimates and the causes are being explored.
Fish migration and reproduction, key elements to provision of the ecosystem services associated with some key fish species (professional fishing and touristic fishing), respond strongly to the duration of the flood events, followed by starting date, peak and frequency. Furthermore, low flows are also important to allow germination of grass species, which contribute to biomass abundance and food availability. 
The fish production was established as the main ecosystem service of the region, which is linked to subsistence (professional fishing), tourism, and recreation (which is linked to real state sector services). 
Identification of preliminary key relationships: 
a. Dam sediment retention reduces availability of nutrients downstream; 
b. Dam sediment retention in increases the water clarity downstream, which is praised by tourists; 
c. Dam sediment retention increases the water clarity downstream, which increases light penetration and may contribute to sub-aquatic plants growth and potential impacts to fishermen activities;
d. Plants and biomass are carried from upstream Parana river and its upper tributaries to nearby reservoirs (e.g. Porto Primavera). As those plants are released to downstream, they affect professional fishing (by entangling fish lines); 
e. Touristic activities (motored water sports) generates noise and interference with professional fishing; 
f. The number of fishermen has been in decline and facing economic difficulties. This groups also demands more access to areas where fishing is restricted for environmental protection.


Principal Investigator


Guilherme Fernandes Marques, Universidade do Rio Grande do Sul (UFRGS)

Co-Principal Investigators (co-PI)


Angelo Antonio Agostinho, Maringá State University

Elimar Pinheiro do Nascimento, Universidade de Brasilia


Amaury Tilmant, Université Laval


Marcelo Olivares, Universidad de Chile.