International Waters learning Exchange & Resource Network

Rivers

Potential Water Quantity related impacts from climate change (flood, drought and scarcity)

  • Risks to physical structures
  • Sediment transport (link with water quality)
  • Low flow / ecological flow requirements (links with water quality)
  • Changing demands from sectors utilising the water resources (especially agriculture)
  • Flooding damage and potential of pollution as a result of flooding [link to Danube Flood Hazard risk work]

Potential Water Quality related impacts from climate change (pollution, ecological flows, sediment)

  • Run-off (agriculture, urban) transporting nutrients and organic matter
  • Point sources from untreated storm drains.
  • Flooding of hazardous sites resulting in toxic pollution loads
  • Impacts of temperature on dissolved oxygen
  • Sediment transport/deposition from increased (and decreased) discharge and impacts on turbidity

Potential Ecosystem related impacts from climate change within river basin systems

  • Change in species distribution due to temperature, dissolved oxygen, transparency, sediment, pollutant, etc.
  • Fisheries - risks from pollution, increased temperature or insufficient flow to maintain oxygen
  • Insufficient water (scarcity, droughts) for irrigation
  • Loss of biodiversity/negative impacts on ecosystem as a whole

Case studies on strategies to adapt to climate change on rivers

Danube River Basin - Strategy on Adaptation to Climate Change

The International Commission for the Protection of the Danube River Basin (ICPDR) has recently prepared a river basin management plan (in accordance with the requirements of the EU Water Framework Directive) and is currently in the process of updating this plan. As part of the plan the ICPDR has developed a strategy that is designed to assist the countries of the Danube Basin implement measures that adapt to a changing climate that is expected to have a significant impact on the water resources of the basin. The strategy responds to the cross-cutting issues of the multiple sectors that utilise the water resources. The Strategy was developed on the basis of expert collaboration in reviewing the climate change scenarios for the basin (including temperature, precipitation extreme events) and evaluating the potential impacts across the basin.  The Strategy also presents an approach for dealing with uncertainty in the estimates.

The ICPDR identified key lessons from developing a strategy for adaptation to climate change within river basins and offered the following suggestions to this Guidance:

  • Creation of a common knowledge base for the whole international river basin on climate change and expected changes - this is a required basis for joint decision making
  • Interdisciplinary approach since climate change is a cross cutting issue
  • Focusing on the basin-wide level on the issues required to be coordinated on the basin-wide level; country-specific issues can be addressed more concretely on the national level
  • Cyclic approach, requiring an update of the strategy and (adaptation) plans on a regular basis, allowing to take more concrete knowledge into account in the future and allowing to deal with uncertainty.
  • Recognising that the time frames (decades) and which are relevant for climate change, are relevant for the socio-economic developments in a basin, e.g. agricultural development, energy infrastructure, population growth etc. and these may impact a river system eve more then climate change and will compound the overall impacts on water resources
Kura Aras River Basin - TDA

In developing a Transboundary Analysis (TDA) as a component of the overall Strategic Action Programme (SAP), the UNDP GEF Kura Aras project (Armenia, Azerbaijan and Georgia) reviewed regional development and climate change/variability trends. This review assessed both the future demand for water resources based on socio-economic trends (economic development from industry/agriculture/power, population growth, etc.) and potential climate change impacts on water resources.

To prepare this informative section within the TDA the project undertook a detailed study focusing on climate issues utilising both material and national expertise from the Second National Communication to the UNFCCC (such information should be investigated at the national level through ministries/institutes responsible for UNFCCC reporting. Projects should identify these information sources during the inception phase)

This detailed study focused on key issues for climate variability and change relevant to the region with data from both observation and models addressing:

  • Observed temperature and precipitation over past decades;
  • Frequency and intensity of extreme events (drought, flooding, frost, wind, etc.);
  • Project climate changes based on outputs from several global circulation models to indicate potential temperature and precipitation changes with linkages to impacts on water resources (both surface and groundwaters);
  • An assessment, based on various scenarios, on overall water resources and the impacts on economic activities within the region.
Tisza River Basin - Integration of land and water management

Over the last 150 years, most of the natural wetlands and floodplains within the Tisza River Basin have been lost through land reclamation for agriculture or developments or flood defence schemes. These natural riverine features offer multiple benefits such as retaining harmful levels of nutrient pollution, buffering flood waters and improving biodiversity.

By developing an integrated management plan, linking issues of land and water management together with concerns of water quantity and quality, the countries are better equipped to address regional issues affecting the river and developing approaches to mitigate the impacts of varying climate and extreme events. For too long the often competing requirements of land management (agriculture, forestry, urban development) have not been involved in helping to develop and implement strategies for water management – which in return can lead, for example, to reduced flood damage to economically and socially important areas.

In developing the Integrated River Basin Management Plan national assessments on potential climate change (based on extensive research) were included in identifying measures for addressing the transboundary problems and in further strengthening the management of land and water. This recognised the importance of wetlands and floodplains in the future measures to mitigate floods and the multiple benefits that wetlands also offer the environment.