Tuul River Basin, Mongolia

Ms.S.Baasansuren, Lecturer

Mongolian University of Sciences and Technology

Ms.J.Otgonbayar, Officer

Water Authority, Mongolia

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

TRB occupies 3.19 % of the total area of Mongolia.

Tuul River Basin has 9 sub-basins.

Catchment area: 49,840 km2

Tuul river Width →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 kmAnnual mean flow 26.6 m3/sec

GEOGRAPHICAL PROPERTIES

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

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 472Basin 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

Land use classification of TRB

WATER RESOURCES IN TUUL RIVER BASIN

Total surface & groundwater resources: 1.28 bln m3/year  

 

Total surface water abstractions, estimated: 425.4 mln m3/year  

 

Total groundwater abstractions, estimated: 818.0 mln m3/year  

 

Sector Total water use of Mongolia Water use of TBR

Drinking water supply 53 27Livestock 93 5

Agriculture 91 2Manufacturing 37 25

Power plant 33 27Mining 65 32Tourism 0.8 0.8

Total water uses 372.8 mln m3/year 118.8 mln m3/year

Hydrological stations observing the Tuul river regime and quality.

downstream ← upstream downstream ← upstream

Comparison of Tuul river water quality in Ulaanbaatar city

Contaminated by the effluents from city sewage plant and industries

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

Surface water pollution leads to lowering of groundwater level.

Observation done within the “Sustainable groundwater management in Mongolia” project.

-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: