End of Basin issues in Mekong Basin Issues facing those living in Tonle Sap /Delta Bio-physical causes /origins of these problems Who is affected? What are their long-term development objectives?

Issues facing those living in Tonle Sap/Delta Natural resource degradation Declining fish population Salinity intrusion and acidity River bank erosion Sedimentation Imbalance water flow in dry and wet season Water shortage in dry season Competing demand for water Flood and inundation Deforestation

Seawater Intrusion in Mekong Delta (2/3) Jan. 2003 Upstream Discharge into Mekong Delta is Key Factor ! Upper Limit of Maximum Salinity in 1985

Flood and inundation

Tidal effect at Delta 0.8 m above sea

Flood-Hazard Areas in the Lower Mekong Basin

Issues facing those living in Tonle Sap/Delta Natural resource degradation Declining fish population Salinity intrusion and acidity River bank erosion Sedimentation Imbalance water flow in dry and wet season Water shortage in dry season Competing demand for water Flood and inundation Deforestation

Deforestation

Bio-physical causes / origins of these problems Population pressure Development interventions Over-fishing Increasing water demand in sector development Increasing use of chemicals Change of hydrological regime Climate change Deforestation

Who is affected? All people in the sub-areas (directly and indirectly) The ecology in the sub-area The biodiversity in the sub-area

Prosperous and peaceful basin What are the long-term development objectives of those at the end of the Basin system? Economic growth Poverty alleviation Prosperous and peaceful basin Mutual benefit and understanding, and cooperation

Irrigation growth Total dry season irrigated cropped areas (ha)

Basin irrigation efficiencies of 90% and 70% Indicative dry season water balance 40% 52% 13-17% of Kratie flow On average 10,400 MCM/month in dry season Basin irrigation efficiencies of 90% and 70%

Mekong Fisheries Total  2 million tonnes Capture Fisheries  1.75 million tonnes Aquaculture  0.25 million tonnes Total value: $1,400 million 40 million people involved full or part-time Non-fish products (shellfish, frogs, insects, aquatic plants)

Flooding 2000 flood 2002 flood and drought 800 people died $400 million damage 2002 flood and drought impact on food security and health

Key Factor of Water Utilization in Mekong Delta

Changes in overall paddy areas and production - 1990 to 2000 80% 60% 40% 20% Production Area Rice production has increased dramatically, to provide for the growing population, meet the countries’ requirements for food sufficiency and, where possible, provide export income. This has been achieved partly by increasing areas under production, and partly by intensification, with rise in areas irrigated and increase in inputs such as fertilisers. Cambodia Lao PDR Thailand Viet Nam