GEOSSAsian Water Cycle Initiative

The 3rd GEOSS Asian WaterCycle Symposium
Beppu, Oita, Japan, 2-4, December 2007
Dr. Sergey MYAGKOVNIGMI of Uzhydromet
72, K.Makhsumov street,
Tashkent, 100052,
Uzbekistan
E-mail: nigmi@albatros.uz

Republic of Uzbekistan

Chirchik-Akhangaran River Basin

Chirchik -Okhangaran river basins is located in theTashkent province. It is the most developed
industrial province in the country. Located innortheastern part of Uzbekistan, between the TianShan Mountain Ranges. Administrative center of theprovince is Tashkent city (2156,3 thousand people).
This river basin include many different goods.
Irrigated area, towns and cities, hydropowerstations, water reservoirs.
Tapping the water resource of the basin to generate
power would mean a sizeable contribution to theincome of the country. Nevertheless, there areissues which need to be addressed in thedevelopment of this basin.

Socio-Economic Information
Agriculture: cotton, grapes and grain, horticulture, poultry and cattle
farming, as well as the silkworm breeding. The valleys are planted withoaks, wild grapes, pistachios, and peanut trees. The province is the only
place in the area to cultivate ambary – a plant out of which rope ismade.
Industry: The province has the most developed industry in the country.
All of the heavy metallurgy industry and a major part of the non-ferrous
metallurgy enterprises are located here. Machinery, chemical, food andconstruction material industries are well developed.
Social Infrastructure: More than 250 state enterprises, 45 joint
ventures and 2632 small and 328 cooperative enterprises are operatingin the province. Railroads and automobile roads cross the territory of theprovince contributing to the intense international and interstate
economic activity. The total length of the railroad network is 354,2 km.
Automobile roads are 6,600 km long, 5,900 km of which is covered withasphalt.

Impacts of Climate Change
Snowmelt induced runoff of rivers of the Chirchik – Okhangaran basin
comprised 60-90% of the total stream flow. The remaining part of
runoff is assigned to glacier melt water and groundwater inflow(i.e. rainfall induced runoff is almost absent in the region).
This demonstration project would assist in monitoring the flow regimes
in the rivers due to climate change.
FloodsSpring and summer flood period is the main phase in the hydrologicalregime of the Central Asian rivers, during which 70 – 85% of the annual
flow is passing through. This time the largest discharge values are being
registered on the main rivers. The character of the flood formation
depends on the different hydrometeorological factors and physical andgeographical features of the river basins, which, being closelyinterconnected, create different conditions of their formation in eachindividual year. With the definite combination of these factors the floods
with the highest volume and height are formed. Sometimes suchanomalies of the water availability of rivers are revealed in a form ofnatural disasters causing significant damage to people and property.

Methods of measurement

VisualStations

Aero visual control

Installation for Snow cover measurement

Different parts of the river basin3349 meters

450 meters

River bed without water

Ikhnach lake (2743 m)

To distinguish the characteristic features and differences in theconditions of the formation of the catastrophic floods it is expedient
to consider the floods with the different genesis in different years.
In 1959 the formation of the outstanding maximum floods wasregistered. That time the catastrophic maximums caused by theexcessive rains were observed on many rivers and ephemeralchannels of the Chirchik – Okhangaran basin.
The proceeding outstanding maximum was registered on Chirchik
river in 1914 which was 1800 m3/sec. Maximum in 1959 was 2160
m3/sec. Let’s consider the qualitative features of the process of thecatastrophic floods formation in 1914 and 1959.
Chirchik is rather big river, the maximum discharges of which arebeing formed mainly by the melt water.
At the same time, the large rain flood was registered on theneighboring Akhangaran river.
Determination of an adequate warning system for floods would be atarget for the demonstration.

Low Stream of River

Upper Stream of River

Dam for Flood Control

Capacity building needs•Education•Training•Research and development•Access to satellite information with heightresolution

Thank you for your attention !