Managing Environmental River Flows

Geographical location:

Asia/Pacific > Southeast Asia > Vietnam

Summary

The project aims to design a national framework and methodology to assess sustainable river flows and ensure a healthy river system within Vietnam. The volume and timing of flows needed to ensure a healthy, sustainable river system is known as environmental flows.

Work needs to focus on a framework adapted to meet the specific needs of Vietnam, taking into account physical and institutional constraints, as well as the availability of certain data, tools, and expertise.

Background

Vietnam's rapid economic growth requires the development of major water supply systems and increases in the use of water for a wide range of purposes. Unfortunately, there has been little consideration of the resulting impacts of changes in river flow regimes and extraction of water on natural river or aquifer processes. The result is that river health suffers and aquifer levels decline. This impacts most on the poorest people.

Under current arrangements managing flows in rivers in Vietnam is not based on a strategic basin-wide assessment of available water and the full range of community needs that depend on that water. Generally, the most upstream water user has first access to water. If flows are insufficient then the downstream water users may finish up with no water at all, even though upstream users have all they need. There is no formal requirement to pass any flows to water users down river for river health or other community benefits. Incorporation of environmental water provisions in water sharing and allocation is a fundamental component of integrated water resource management (IWRM).

The study of environmental flows has made great advances in recent years. Water managers and scientists alike now acknowledge the importance of holistic approaches to environmental flow assessment, which combine hydrologic, ecological, and social criteria, as well as comprehensive approaches to environmental flow implementation, which formally integrate environmental flow needs into river basin planning and management.

Leading river scientists representing 10 international scientific organizations have developed a framework called Ecological Limits of Hydrologic Alteration ( ELOHA2). Through a series of hydrologic and ecological analyses, ELOHA generates relationships between flow alteration and ecological response for groups of similar rivers throughout the country. By informing decision makers of the tradeoffs between flow levels and ecosystem response, these relationships provide a sound scientific basis for setting environmental flow standards nationwide. Furthermore, ELOHA generates (or uses existing) hydrologic models, which can serve as decision support systems for integrating environmental flows into water sharing and river operations.

Objectives

Establish a framework and methodology to assess sustainable river flows and incorporate provisions into water sharing and river operations to ensure a healthy river system in Vietnam.

Solution

The project will undertake the development of a framework to assess and provide sustainable river flows through structured consultation and negotiation within the DWRM, and with other Ministries, provincial representatives and national and international experts.

1. Situation analysis of current management of flows in river
2. Documentation of good practice principles, framework elements and assessment processes.
3. Documentation of national environmental flows framework and processes.
4. Action plans and measures, including identification of pilot river basins for the application of the approach.
5. Identification of legal issues