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Rakhmatov Norkobil, Associate professor of technical science at the department "Hydrotechnical construction and engineering structures" Tashkent institute of irrigation and agriculture mechanization engineers (TIIAME), Uzbekistan E-mail: rnr08@yandex.com
WATER RESOURCES MANAGEMENT OF SIRDARYA RIVER
Abstract. The Syrdarya water basin association is an intergovernmental coordinating organization which is part of the interstate commission (ICWC) on Aral Sea rescue in the role of "Executor". Transboundary waters are distributed to Kyrgyzstan, Kazakhstan, Tajikistan and Uzbekistan with the help of hydraulic structures within the association.
In order to avoid disagreements between "water consumers" in distributing the transboundary waters of Syrdarya, the operating organization should have up-to-date information on the amount of water flowing into Syrdarya River and on consumption of water distributed among users.
This article describes the experience of Syrdarya Basin Water-Management Association in improving data collection and management of hydrosystems within its balance.
Keywords: river, basin, water management, consumption, transboundary water, hydraulic engineering structure.
In 1988, the Syrdarya Basin Water-Management Association was established and limited water consumption was introduced to control the water management complex of the Syrdarya river.
The objectives of Basin Water-Management Association are to supply water to the consumers in accordance with the limits of regime control of the Naryn-Syrdarya cascade, water run provision in Chardara reservoir, monitoring the ecological state and river water quality.
The water management complex of the Basin Water-Management Association delivers ofwaterworks facility system, water intake of hydraulic structures on the Naryn, Syrdarya, Karadarya, Chirchik rivers, and also interrepublican canals, "Dustlik", Yujno-golodostepsky and the head section of the budget and finance committee with facilities (49 km). The Basin Water-Management Association serves along the stem stream from Toktogulsky to Chardara reservoir over 1000 kilometers (Fig. 1). The hydraulic structure 198 are on the balance of the Basin Water-
Management Association, including three large river waterworks facility.
The discharge tolerance of the facilities is 20 ... 2500 m3/s, the hydraulic performance of "Dustlik" and Yujnogolodostepsky canals and the head section of the budget and finance committee reaches up to 400 m3/s. 243 pumping stations and small backings are under control of the Basin Water-Management Association.
Table 1.
Irrigated area ths.ha
Syrdarya 3200
Naryn- Syrdarya 1770.7
Kyrgyzstan 59.9
Kazakhstan 491
Tajikistan 185.3
Uzbekistan 1039.5
Water intakes from rivers and subordinate canals are counted in 445 points: at 21 head intakes, 36 stationary pumping stations, 172 temporary
Section 6. Technical sciences
pumping stations and branches from main canals. Under centralized management until 1991, the Naryn-Syrdarya reservoir cascade operated in irrigation mode with agricultural priority. The development of irrigated agriculture in the Syrdarya basin was carried out at the expense of measures for the economical and rational use of local water resources. It is considered that the further development of irrigation will lead to the complete exhaustion of water resources in 2000. In terms of the formation five sovereign states "Syrdarya" in Central Asia in 1991, it has become an "international watercourse" according to modern terminology. There was to organize use of "transboundary water resources" as river basin and as the whole basin of Aral Sea. The Inter-State Commission for Water Management was established in 1992 and pick up the management of Aral Sea basin water resources.
The Inter-State Commission for Water Management preserving continuity in management has to be one of the executive bodies of Basin Water-Management Association. The Inter-State Commission for Water Management annually approves water withdrawal limits for each water-consuming country and water supply volume for Aral Sea. In accordance with the Intergovernmental Agreement of Central Asia on the complex exploitation and protection of Syrdarya water resources water intakes are limited from 1992.
Annual water withdrawal limits normal water content in Countries; Kazakhstan- 8.2 km3 (38%), Kyrgyzstan-0.22 km3 (1%), Tajikistan-2.0 km3 (9%) and Uzbekistan-11.15 km3 (52%). In case of water content changes (water shortage or high water year), the amount of water intake limits is adjusted with the appropriate justification and approval of the InterState Commission for Water Management. Having the forecast from Hydromet Chiefs and preliminary proposals on water withdrawal limits from each basin state via canals and pumping stations, the Basin Water-Management Association makes calculations of Naryn-Syrdarya reservoir cascade operating mode and several options taking into account the
water content of the year and offers the Inter-State Commission for Water Managementas the best one.
The delivered project of Naryn-Syrdarya reservoir cascade regime submitted by the Inter-State Commission for Water Management contains a summary information calculations and date explanation of irrigation consumptive water use by canals and pumping stations. The project is submitted 10 days before the meeting to each member of Inter-State Commission for Water Management for studying and giving subsequent comments and suggestions.
The collective decision of the Inter-State Commission for Water Management members is approved only with the consent of all members. The approved project is recommended for further discussion by the working group of power engineers, water workers and preparation the intergovernmental agreement on water and energy resources exploitation for a certain period.
Implementation of decisions the Inter-State Commission for Water Management is carried out by the Basin Water-Management Association and its territorial departments. The Basin Water-Management Association, shall have the right to adjust the limits within ± 10% on the basis of official notification of this water users depending on water situation and rivers content. If situation so requires a larger adjustment of the Basin Water-Management Association, the Inter-State Commission for Water Management delivers relevant calculations and a new adjusted regime of Naryn-Syrdarya reservoir cascade. After agreement the Inter-State Commission for Water Management provides the official guidance document for the Basin Water-Management Association.
Despite a high degree of regulation (93%) of Syrdarya runoff makes possible to effectively supply water to irrigated agriculture, industry, energy, utilities. The implementation of limits has some difficulties caused difference of macroeconomic interests in Central Asia.
The Toktogul reservoir has been operating as an energy regime since 1995. Water pass in autumn-winter period sometimes up to 8.5, in vegetation period 5-6.5 km3. Due to the increased passes in autumn-winter period, the Kayrakkum and Chardara reservoirs are prematurely filled. However, an excessive discharge of water into the Arnasai depression is allowed, farmlands and settlements are flooded. In 1992-2002, more than 27 km3 ofwater was dumped into Arnasay.
In autumn-summer period, artificially created shortage of water resources leads to reduction of limited water supply in the Republic of Kazakhstan, Tajikistan and Uzbekistan, causing damage to agricultural production. In continuation of Toktogul reservoirs, the operation regime of the Kayrakkum and Chardara reservoirs were completely deformed.
Average annual natural river flow in autumn-winter periods at the Toktogul hydroelectric station is 2.5 km3, actually reaches 8.5 km3, or more than 3 times the natural indicator. Summer mode changed
in the opposite direction: average long-term runoff 9-10 km3, reservoir passes 4.5-6.5 km3, or 1.4-2.4 times less than the natural value. This is largely responsible for floods in winter and in summer for artificial water shortage.
The signed agreements among Kazakhstan, Kyr-gyzstan and Uzbekistan on compensatory energy supplies for Toktogul reservoir pass in vegetation period are often led to water shortage for water consumer. Additional complication of water management that, paid water by other countries entraps in Kayrakkum reservoir in Tajikistan without passing to Kazakhstan and Uzbekistan. The absence of a long-term interstate agreement forces out of follow by seasonal agreements only.
In connection with above mentioned conditions, necessity arises to develop an agreed position to prevent a possible violation of joint management and cooperation on rivers. The main guiding principle should be strict adherence the norms of international water law, where natural flow is accepted and relevant water management principles.
Figure 1. Schematic of the Syr Darya River
Section б. Technical sciences
References:
1. Rakhmatov N. Management system improving of transponder water recourses of Sydarya basin. Regional consultative seminary «Сотрудничество в области совместного использования водных ресурсов в Центральной Азии: опыт прошлого и проблемы будещего» - Almata, 26-28 сентябрь 2GG2.-P. 235-237.
2. Rakhmatov N. Правовые вопросы обеспечения безопасности ГТС на трансграничных водных объектах бассейна Сырдарьи. Узбекский журнал «Irrigatsya va melioratsiya».- Tashkent, 2G17.-№ 4 (1G),- P. 31-32.
3. Rakhmatov N. Маълумотлар базасини яратиш йулидаги Сирдарё давзаси сув хужалик бирлашмасининг тажрибаси. Узбекский журнал «Irrigatsya va melioratsiya».- Tashkent, 2G18.- № 2 (12).- P. 31-33.
