Zarafshan Valley and its Downstream
The Zarafshan river, which is considered the main water source of Samarkand and Bukhara, originates from the Zarafshan glacier, located at an altitude of 3154 meters, at the junction of the Zarafshan ridges in Turkestan from the north and Hisar from the south. The glacier is 24.7 km long, 1.7 km 2 wide, and 200 m3 thick. Its capacity is 40.8 sq/km4.
Zarafshan is called Mastchoh until the place where its first huge confluent - Fandaryo flows. The Mastchoh river begins at the lower limit of the Zarafshan glacier at an altitude of 1775 m and flows westward along a single bed along a high rocky and narrow mountain gorge. The width of the upper part of the river is 25 m, and every kilometer, on average, it goes down 7 m, so it flows very fast and carries with it loose rocks such as sand and mud.
205 km below the Zarafshan glacier, above the village of Ainiy (ancient Varzaminor), the water of the Fabdarya joins the Mastchoh river from the left side, and from this place it gets the name Zarafshan. The water basin of the Mastchoh river is equal to 4660 sq.km and it is mainly formed by the confluence of the waters of three rivers - Iskandararyo, Yagnob and Pasrud. The upper reaches of Iskandararya is called Karakoldarya, and it starts from small glaciers located on the northern slopes of the Hisar mountain in the ridges of Kokhisafid, Tagisiyo, Siyokuh and Yahab mountains. From the place where the Mura tributary flows, it takes the name of Karakoldarya Saritog.
Saritog River flows into Iskanderkol. The length of the lake is 3260 m, the width is 2900 m, the surface is 3.4 km2. Saritog flows out of the lake under the name of Iskandaryo. 22 km below Iskanderkol, the Yagnob river flows into it from the right side, and from here it is called Fandaryo.
The Yagnob river starts from the Yagnob glacier, which is located at an altitude of 3650 m in the eastern part of the Hisar ridges in the Kumbel pass region. The Takali confluent joins it from the right side 10 km from the source of the Yaghnob river. At a distance of more than 116 km to the south, the upper stream of Zarafshan flows almost parallel to Mastchoh from east to west, through a deep and narrow gorge. The water basin of the Yagnob river is equal to 1646.43 sq/km.
4 km below the confluence of the Yagnob river, the stream of the Pasrud ​​river flows into Fandarya from the left side. It starts from the Kaznok glacier at an altitude of 3600 m near the Kolikalon pass on the southern slope of the Pasrud ​​Zarafshan ridge, and its water capacity is 375.47 sq/km. From the confluence of Pasrud ​​to the Mastchoh river, the Fandaryo flows through a narrow gorge at a distance of 24.5 km. The total capacity of the Fandaryo water basin (including Iskandardaryo, Yagnob and Pasrud ​​rivers) is 3250 sq/km.
56 km below the confluence of the Mastchoh and Fandarya valleys, opposite the village of Dashtigozi, the Kishtutdarya stream joins Zarafshon from the left side. The upper reaches of the Kishtut Darya are formed by the confluence of the Sarimat and Archamaidan tributaries. Sarimat starts from the glaciers located at an altitude of 3700 m on the northeastern slope of the Punjab Pass. Archamaydon tributary joins Sarimat 20 km from the right side. This tributary flows from a small glacier located on the northwestern slope of the Dokdon Pass at an altitude of 3773 m. 5 km below the confluence of these two tributaries, the water of the third tributary, Vorukh, flows into the river from the left side. Vorukh receives the flow of the Artuch tributary from the right side, opposite the village of Kuleli, at a distance of 17 km, and receives the name Kishtut. Kishtut flows in an 11 km gorge and joins Zarafshan.
Until it joins the Kishtut, Zarafshan flows through a narrow valley between the mountains. The width of the oasis does not exceed 1.5-2 km. After receiving the Kishtut stream, Zarafshan emerges from the mountain gorge and flows through a rather wide valley. The valley with a width of 5-6 km widens towards the west. 9 km above the city of Panjakent, the third of the large tributaries of Zarafshon - Magiyandarya, or rather Mugiyandarya, joins. Local residents call it "Mugdarya".
Mugiyandarya is formed by the confluence of Shinkdarya. Shinkdarya begins from small glaciers on the northeastern slope of the Punjab Pass. Its upper stream consists of almost a series of lakes, and at a distance of 37 km, it forms Khazorchashma, Morguzar, Nofin and other lakes and flows into the Magiyandarya from the right side. The upper course of the Magiyandarya is called Karasuv, and it starts from the eastern part of the Gova pass. 31.5 km below Karasuv, near the village of Mugiyan, the tributary of the same name pours its water from the left side. From here, it is called Margiyandarya. After receiving the flow of Shinkdarya, Margiyandaryo joins Zarafshan 22 km below.
In addition to Fandarya, Kishtutdarya and Magiyandarya, about 50 mountain ranges from Turkestan, Hisar and Zarafshan ridges connect to Zarafshon. These streams dry up with the beginning of summer.
The total capacity of the Zarafshan river basin is 10,200 sq/km up to the Dupul water measuring station, and 11,782 sq/km after the Magiyandarya confluence.
Below Panjakent, Zarafshan does not receive any tributaries, but begins to spend its life-giving waters along artificial irrigation canals. 15 km west of Panjakent, it rises to a wide plain. This is a valley formed by the alluvial deposits of the Zarafshan River. The northern border of the valley is connected to the high and low hills located at the southern foothills of the Nurota ridges, and the southern border is connected to the hills of the Zarafshan ridge. The width of this valley reaches 35-40 km and in some places even more. As soon as it reaches the plain, the Zarafshan river expands. It forms islands and flows along several valleys. The width of the river bed in this region reaches 1-1.5 km. The big and small irrigation arteries, which cut both banks of Zarafshan, start from this district. Most of these irrigation arteries started from the vicinity of Ravothoja, mentioned in historical sources (first in the works of medieval Arab geographers) under the name "Varqsar", i.e. "head of the dam". The reason for that is the main structure of the Dargom canal, which supplies water to Samarkand and its surroundings, has been installed in this place for a long time. Today, the main hydrotechnical facility of a number of main canals from both banks of Zarafshan is located in this place. It was built and commissioned in 1926-1929.
7 km northeast of the city of Samarkand, near the height of Choponota, Zarafshan divides into the northern basin - Akhdarya and the southern basin - Karadarya, and forms Mionkol island. Mionkol Island is 100 km long and 12-15 km wide. Due to its favorable geographical conditions, Mionkol was developed in ancient times and became the most prosperous part of the valley. In Mionkol region of the valley, 22 canals start from Okdarya and 12 from Karadarya. In the eastern part of Mionkol, the width of the valley is 30-35 km, and it narrows towards the west. It is no more than 10-12 km near Kattakorgan region.
In the middle of the valley, many streams flow from the southern slope of the Nurota Ridge and join Zarafshan. Their flood waters are poured into this river in the spring, and during the summer season, they are drawn along the irrigation networks. Some are completely dry. These streams play almost no role in the change of Zarafshan river flow.
At the confluence of Okdarya and Karadarya, the valley widens again and its width reaches 18-20 km. It cuts through low and high hills from the north and south sides and narrows to the west. Near the city of Navoi, its width does not exceed 8-10 km. Konimekh oasis separates from the valley in Navoi region and breaks into the heart of the desert to the north-west. Its width reaches 3-4 km. From the north, it is bordered by the high hills connected with the western foothills of the Nurota ridge, and from the south by the hills of Oftobachi, which join the Konimekh desert.
Starting below the city of Navoi, Zarafshan flows through the desert, which is almost surrounded on both sides. The river washes the southern foothills of the Konomekh desert along the right bank and the northern foothills of Cholimak along the left bank, and then flows into the narrow Khazora Darband, compressed by the upper deserts from the north and south sides. In this region, the valley becomes extremely narrow. Its width does not exceed 2.5-3 km. From the confluence of Akdarya and Karadarya to Hazora, 12 main canals start from Zarafshan. After leaving Hazara Darbandi, it goes towards the lower part of its valley. Upon entering this part of the valley, Zarafshan turns its flow direction to the southwest. In this direction, it forms the Bukhara oasis in a conical shape. The oasis of Bukhara is bordered by Kyzylkum from the north and west through ancient irrigated lands covered by shifting sands. It is approached from the east by Cholimalik and Kyziltepa and Kuyimozor hills, and from the south by the Karshi desert. Its width reaches 65 km.
7 km west of Kiziltepa, its deltaic tributary Vonkent Daryo separates from Zarafshan. The place where Vobkent Darya begins is known as Kharkhor. 10 km below Kharkhor begins the Shahrud highway, which supplies Bukhara and its surroundings with water. This place is called Duoba. From here, Zarafshan will be called Karakoldarya. About 78 km below Duoba, near the Yakkatut station, the ancient dry valley of Zarafshan - Mokhondaryo separates from the right bank of Karakoldarya to the northwest. In this region, the Karakol Darya leaves the Bukhara oasis and flows along a narrow valley towards its lowest stream, the Karakol oasis. The width of the valley here does not exceed 2.5-3 km. 25 km below Yakkatut, Zarafshan-Karakoldarya forms its lowest fan-shaped oasis of the same name. The Karakol oasis is 20 km long and more than 35 km wide. It stretches from the east and northwest to the southwest. It is surrounded by hills approaching the Karshi desert and the eastern part of the Kizylkum, which is covered with sandy dunes on the other three sides.
At present, 35 main canals laid out along both banks of Zarafshan in the Bukhara and Karakol parts of the valley supply irrigation systems with water. Among them, the Kalkanota, Konimekh, Shofrikon, Sultanabad, Pirmast, Kharkhanrud, Vobkentdaryo, Shahrud, Romitan, Khairabad and Saribazar canals are the largest irrigation systems in the Bukhara oasis.
The water of the Zarafshan river, which is drawn from the upper part of the valley to the irrigation networks, ends completely in the Karakol oasis. Only its discharge flows to the south through the Taigyr basin. There is almost no water in Taigyr, and its core is always dry due to lack of water. Only during the winter and spring seasons, excess waste water is dumped into Taigyr. Taigyr flows into Dengizkol located southeast of Karakol. At present, the Zarafshan River flows over 781 km and ends in Kyzylkum, less than 25 km from Amudarya.
Water supply of the irrigated agricultural land of Zarafshan Valley, which was cultivated and developed as a result of the work of farmers over the centuries, has always depended on the stable regime of the river flow. According to V.L. Schultz’s classification, Zarafshan and its upper tributaries are among the rivers filled by high mountain glaciers and permanent snows. That is why its flow is constant. 34 percent of the Zarafshan stream is formed from ground water, 1 percent from glacier water, 34 percent from snow and the rest from rain water. Therefore, seasonal changes in the water balance of Zarafshan depend on weather conditions and the amount of precipitation. Zarafshan floods pass for a long time, and usually one of them is almost connected to the other. For example, the first flood caused by melting snow in the mountains occurs in May-June, and the second flood caused by glaciers occurs in July-September.
(to be continued)
Taken from Mukhammadjonov A.R, Quyi Zarafshon vodiysining sug`orilish tarixi. Toshkent 1972.