1. Tuul River Basin, Mongolia Ms.S.Baasansuren, Lecturer Mongolian University of Sciences and Technology Ms.J.Otgonbayar, Officer Water Authority, Mongolia

2. Mongolia has 3 hydrological drainage basins. Tuul River Basin-TRB belongs to Arctic Ocean Basin.

3. TRB occupies 3.19 % of the total area of Mongolia.

4. Tuul River Basin has 9 sub-basins. Catchment area: 49,840 km 2

5. Tuul riverWidth →35-75 m Depth → 0.8-3.5 m Topography The basin covers mountain, forest and steppe area within Khan Khentii and Bogd Uul strictly protected areas, Gorkhi-Terelj Natural Park and Khustai Nuruu Natural Reserve. Altitude ranges 1200-2700 m. Geology It consists of Cenozoic sand, gravel and clay; Mesozoic granites, sandstones and siltstones and Palaeozoic shales and conglomerates. The alluvial unconfined aquifer thickness of Tuul river valley is 25-30 m or more. Rainfall Average annual rainfall 232 mm River length and annual flow Length of Tuul river is 704 km Annual mean flow 26.6 m 3 /sec GEOGRAPHICAL PROPERTIES

6. Tuul river recharge: GW (26%), melted snow (5%) and rain (69%).

7. Situation Tuul river basin includes 7 districts of Ulaanbaatar city, 19 small administrative units of Tuv, Bulgan, Selenge provinces. Total population in the basin 1 067 472 Basin covers the highest populated part of Mongolia. Population main city The capital of Mongolia is Ulaanbaatar -1 046 921 Water Poverty Index parameters: Water scarcity index 0.025 Safe drinking water accessibility 0.379 Vulnerability index for TRB 0.441* Water pollution 0.420 Ecosystem deterioration 0.829 * UNEP report “Freshwater under threat Northeast Asia” DEMOGRAPHIC PROPERTIES

8. Land use classification of TRB

9. WATER RESOURCES IN TUUL RIVER BASIN Total surface & groundwater resources: 1.28 bln m 3 /year Total surface water abstractions, estimated: 425.4 mln m 3 /year Total groundwater abstractions, estimated: 818.0 mln m 3 /year

10. SectorTotal water use of MongoliaWater use of TBR Drinking water supply5327 Livestock935 Agriculture912 Manufacturing3725 Power plant3327 Mining6532 Tourism0.8 Total water uses372.8 mln m 3 /year118.8 mln m 3 /year

11. Hydrological stations observing the Tuul river regime and quality.

12. downstream ← upstream downstream ← upstream Comparison of Tuul river water quality in Ulaanbaatar city Contaminated by the effluents from city sewage plant and industries

13. Downstream of the Tuul river polluted by silt & mud from mining activities in Zaamar, Tuv provinc e.

14. Surface water pollution leads to lowering of groundwater level. Observation done within the “Sustainable groundwater management in Mongolia” project.

15. - Increasing urbanization, deforestation, overgrazing pasture, waste water mismanagement, mineral resources exploitation destructing the Tuul river ecosystem. - Surface water pollution threatens safety of drinking water resources. Setting up “Tuul River Basin Board” is underway. Work out”Integrated Water Management Plan of Tuul Tiver Basin” is vital. CONCLUSION: