Hydrology as a science

9. SAVDOLAR
Ma'lumki, daryolardagi suv miqdori yil davomida mavsumdan mavsumga va yildan yilga o'zgarib turadi. Mamlakatimiz sharoitida qishloq xo‘jaligida suvga bo‘lgan talab ortib borayotgan fasllarda ko‘pgina daryo va soylarda suv keskin kamayib, ayrim hollarda butunlay qurib qoladi. Bunday sharoitda daryo va soylardan to‘liq va samarali foydalanish uchun ularning oqim rejimini nazorat qilish zarur. Daryolarda sun’iy ko‘llar-suv omborlari qurish orqali bu muammo hal qilinadi.
Ayniqsa, mamlakatimiz kabi qurg‘oqchil va dehqonchilik bilan sug‘oriladigan hududlarda suv omborlarini qurish zarur. Ekinlarni suv bilan ta'minlashdan tashqari, ko'pchilik suv omborlari gidroenergetika, baliqchilikni rivojlantirish, yirik sanoat korxonalari va shaharlarni suv ta'minoti uchun ishlatiladi.
Yer sharida ko'plab suv omborlari qurilgan. Dunyodagi eng katta suv ombori Keniya, Tanzaniya, Ugandada joylashgan Viktoriya-Nil daryosida qurilgan Ouen Fols (Viktoriya) suv omboridir. Uning suv sig'imi 205 km3 (Viktoriya ko'li bilan birga) va Nil daryosi oqimini yildan-yilga nazorat qilish uchun mo'ljallangan. Rossiyaning Bratsk (Angara daryosi), Krasnoyarsk (Yenisey daryosi), Kuybishev (Volga) va Qozog'istondagi Buxoro (Irtish) kabi suv omborlari nafaqat bu mamlakatlarda, balki butun Yevroosiyo qit'asidagi eng yirik suv omborlari hisoblanadi.


10.RESERVOIRS
It is known that the amount of water in rivers varies from season to season throughout the year and from year to year. In the conditions of our country, during the seasons when the demand for water in agriculture increases, the water in many rivers and streams decreases sharply, and in some cases completely dries up. In such conditions, it is necessary to control the flow regime of rivers and streams in order to use them fully and efficiently. This problem will be solved by building artificial lakes-reservoirs on the rivers.
Construction of reservoirs is especially necessary in arid and agriculturally irrigated areas such as our country. In addition to providing water to crops, most reservoirs will be used for hydropower, fisheries development, large industrial enterprises and urban water supply.
Many reservoirs have been built on the globe. The largest reservoir in the world is the Owen Fols (Victoria) Reservoir, built on the Victoria-Nile River, located in Kenya, Tanzania, Uganda. Its water capacity is 205 km3 (including Lake Victoria) and is designed to control the flow of the Nile River year after year. Russia’s Reservoirs such as Bratsk (Angara River), Krasnoyarsk (Yenisei River), Kuibyshev (Volga), and Bukhtarma (Irtysh) in Kazakhstan are the largest reservoirs not only in these countries, but also on the entire Eurasian continent.