The world can be divided into hundreds of river basins ranging in size from the largest, the Amazon basin, to many small ones. The lower part of these basins, the deltas, are home to over half a billion people and locate both productive ecosystems and economic hotspots.

What are the issues?

Many of these river basins and deltas have serious problems ranging from water distribution, water shortage, flooding to pollution and presenting serious risks to people and ecosystems. For example:

  • Distribution of water between upstream and downstream users requires adequate management of the water resources in a basin.
  • Water shortage as well as flooding are becoming more severe due to climate change and require long-term and adaptive planning.
  • Land use changes have amongst other things, an effect on water availability and quality;
  • Pollution through diffuse (e.g. agrochemicals) and point source discharges (waste water) have a considerable effect on water quality.

Technical solutions to water management are often difficult to implement cost-effectively for many reasons. These include the scale and inter-jurisdictional complexity of water systems, their multiple uses of which many conflict, impeding cooperation and cost sharing. In some cases, there is also skewed interdependence, for example where upstream jurisdictions control the water on which downstream jurisdictions depend, or where upstream jurisdictions undertake major developments that have adverse downstream impacts.

The development and sustainable use of water resources in the basins and deltas requires allocation of water among competing human activities. This implies decision making in complex situations, often with conflicting interests. Careful planning and analysis are required to support such decisions, taking into account technical, economic and environmental aspects in a specific social, cultural and institutional context. Intensive and timely consultation of all stakeholders is of utmost importance.

Role of SEA

Adequate management of water resources by the government requires strategic planning of river basins and deltas. Effective use of SEA (Strategic Environmental Assessment) can enhance the quality of river basin and delta planning, by assessing its contribution to sustainable and inclusive development and by reducing negative consequences for underprivileged groups in society. Furthermore, SEA plays a proactive role in integrating such planning in the broader context of transboundary and regional development planning and in aligning these activities with existing national sector policies.


SEA and IWRM (Integrated Water Resources Management ) have a lot in common. IWRM is the main concept that is used in river basins and delta planning. The recently developed Dutch Delta Approach can be considered as a specific form of IWRM applied for delta planning. IWRM has been the accepted management paradigm for efficient, equitable and sustainable management of water resources since the early 1990s. SEA can build upon and reinforce IWRM and thus add quality to river basin and delta planning. SEA adds various components to the process, such as stakeholder analysis, development of alternatives, comparative assessment of the impacts of the alternatives, quality review of the process and report. For more information on SEA and IWRM, please read our views on SEA for river basin and delta planning. 


Main decisions

Main issues for decision making

Water (and land) management

To be addressed in SEA

  • Governance of water management
  • Alternative governance models: public, public-private, level of decentralisation, funding mechanisms, decision power
  • Water distribution agreement between up- and downstream countries or regions
  • Water distribution alternatives
  • River stabilisation (flood protection dikes, channelisation, groins, dredging, training works, etc.)
  • Alternatives ranging from a natural to a completely regulated river system
  • Water allocation to different uses and users, such as maintenance of ecosystems and ecosystem services, agriculture, hydropower, public water supply, process water, navigation, etc.
  • Alternative combinations of water allocation for different uses and users
  • Land use management and planning (combat salinisation, soil subsidence, soil erosion and soil degradation)
  • Land use planning alternatives
  • Flood risk management and early warning
  • Flood adaptation measures (including early warning) versus maximum flood protection;
  • Zoning and differentiated safety levels based on magnitude of flood damage;
  • Restoration of water related ecosystems to rehabilitate ecosystem services, e.g. for nature conservation, enhanced resilience against climate change, land and water productivity, water quality, etc.
  • Site alternatives; connectivity and quality of water related ecosystem; type and magnitude of restoration interventions; alternative management and exploitation regimes.

Water quality

To be addressed in SEA

  • Use of agro-chemicals (diffuse pollution)
  • Alternatives to avoid and reduce the use of agro-chemicals
  • Discharge of polluted water (point source pollution)
  • Alternatives to avoid, reduce and re-use water discharges
  • Surface and groundwater salinity intrusion
  • Alternatives to reduce or adapt to salinity

Major projects

To be addressed in ESIA

  • River training or channelisation works
  • Coastal defence works
  • Dredging works
  • Dams and reservoirs (single or multipurpose)
  • Hydropower projects
  • Irrigation schemes
  • Ground water extraction
  • Water diversion (inter-basin transfer)
  • Ports and harbours
  • Alternatives (siting, size, design, applied technologies, timing of construction, operational regime, etc.) 
  • Mitigation, compensation and offset measures
  • Environmental and social management plan