Evolution in Recognition of theIssue Terminology Main Objectives “Sanitary” Flows (static or discrete Dilution values) Minimum Flows (static or discrete Downstream Water Uses values) Third Party Impacts In-stream Flows (hydrographs) Fluvial Geomorphology / Ictiofauna Ecological Flows (hydrographs) Species / Biota Downstream Flow Regimes Ecosystems + return flows (hydrographs + adaptation)3
Environmental/Ecological Flows - Timeline Until 1960s: Water management in developed nations focused largely on maximizing flood protection, water supplies and hydropower generation. 1970s and 1980s: Ecological and economic effects of hydroelectric projects prompted scientists to seek ways to modify reservoir operation to maintain target fish species (salmon); The initial focus was to determine the minimum flow necessary to preserve individual species. The minimum flows concept evolved to instream flow objectives. 1990s: Scientists realized that the biological and social systems supported by rivers are too complex to be represented by a single minimum flow requirement; Restoring and maintaining more comprehensive environmental flows gained increasing support. Scientific methods to define downstream flow regimes focusing on maintaining a broader spectrum of reverine species, processes and services. 2007: The Brisbane Declaration on Environmental Flows was endorsed by more than 750 practioners from more than 50 countries. The declaration announced an official pledge to work together to protect and restore the world’s river and lakes; By 2010: Many countries had adopted environmental flow policies.
Project Location Tingo María PERU Huánuco LIMARoad Distance Lima – Huánuco : 420 kmRoad Distance Huánuco – Obra : 130 km
Project Characteristics Dam Type Rockfill Concrete Face High 199 meters Length 400 meters Reservoir Storage Volume 345 hm³ Reservoir Area 4,66 km² Aduction Tunnel Length 15,6 km Diameter 7,6 m Power and Generation Main Powerhouse 400 MW PCH 6 MW Execution Period 54 months Investment USD 1.2 billion
Project Location Peru - Ley de Recursos Hídricos (Water Resources Act): • Ecological Flow Definition: The water volume that has to be kept in natural systems for the protection and conservation of local ecosystems, the landscape aesthetics or other aspects with cultural and scientific interests; • The Water Authority in Peru will establish the ecological flow in each river; • Ecological Flows will be defined in each basin’s Water Resources Management Plan. For the definition of the Ecological Flow specific studies will be performed for each stretch of the basin. Projects with water exploitation to produce energy must perform specific studies to determine the Ecological Flows for the affected stretch; The Water Authority in Peru (ANA) has not yet established a standard methodology to determine ecological flows.
Ecological Flow Management Plan Phase 0 – Adjusting location to reduce length of impacted reach (improved hydrology); Phase 1 – Understanding systems characteristics (hydrology, ecosystem, species, topography, water uses, etc.) and validating the proposed approach (mathematical modeling) – critical to preserve and/or restore key tributaries; Phase 2 – Improve knowledge of the system, refine and consolidate modeling framework, identify critical areas and issues. Develop a blueprint to resolving critical obstacles; Phase 3- Implementation of physical interventions; Phase 4 – Operational – continuous monitoring and adjustment to changing conditions. Carachama (Chaetostoma sp.)
Lessons Learned• Increasing Complexity • Understanding the Characteristics of the Ecosystem; • Incorporate ecological flow objectives early (upstream) in your decisions making process (project identification); • Definition of objectives (target species, sediment transport, cultural values, existing and potential water uses, connectivity, etc.)• No “one size fits” all formula • Focus on principles and best practices – flexibility11
Ecological Flow Management Plan Partnership involving the Government of Peru, IDB and Odebrecht; Beyond the project specific solutions the process is developing and disseminating knowledge to contribute to development of regulatory frameworks and methodologies as well as to improved solutions for future projects. AXIS OF THE DAM DIVERTION TUNNEL OUTLET
THANK YOULuiz Gabriel Todt de Azevedogazevedo@odebrecht.com