update Updated
category News
Implementation of Ecological Flows in Water Planning by Sub-Basins: Experiences of Peru and FAO within the Framework of SDG6 Implementation.
The determination of ecological or environmental flows is a crucial component of integrated water resources management and water security in watersheds worldwide. In this regard, Peru, through its National Water Authority (ANA) and in collaboration with the FAO’s Land and Water Division, carried out two pilot projects to implement a holistic method for calculating ecological flow. This approach follows a precautionary principle and water planning framework, incorporating the use of the “ecohydrological threat index” to assess pressures and threats to aquatic ecosystems such as rivers, lakes, estuaries, and wetlands. Based on this index, four possible ecological flow scenarios were determined through the calculation of ecological flow duration curves at a monthly level, under the “natural river” paradigm.
The pilots were conducted in 2024 in the Pisco and Huallaga river basins. The Pisco River basin, located on the Pacific slope, spans the geographical regions of the Pacific desert and the Andean region, while the Huallaga River basin is on the Amazon slope, in the high jungle region. Based on the applied methodology, in addition to estimating ecological flow, it was also possible to assess the level of water stress within the framework of SDG 6, Target 6.4.2. The pilots utilized modeling tools such as SWAT (The Soil & Water Assessment Tool) and WEAP (Water Evaluation And Planning System), as well as official data available in Peru on ecological, hydrological, and socio-economic aspects.
The results of these pilots were shared at the international workshop “Environmental Flows and Disaggregation of Water Stress Levels by Basin and Sub-basin – Peru’s Experience,” held in Lima from February 2 to 4, 2025, with the participation of representatives from Brazil, Chile, Colombia, El Salvador, and Mexico.
Erick GARCIA GONZALES, Specialist in ecohydrology and remote sensing, National Water Authority – Peru