Some results of the study of Otrar oasis irrigation systems
The irrigation detachment of the South Kazakhstan Expedition of the Academy of Sciences of the Kazakh SSR continued to study the irrigation systems of the Otrar oasis. The routes of five systems were surveyed: Sangyl-Aryk, Altyn-Aryk, Kara-Kuvchun-Aryk, Timur-Aryk and Ak-Aryk. The main canals, except Ak-Aryk, are brought out of the Arys River. The source of the latter was the Syr Darya.
Sangyl-Aryk is currently a heavily swollen ramparts. The average width of the channel along the outer base is 35 m, the width between the ramparts is 7 m, the height of the ramparts is 0.7 m. The length of the route is 20 km. During the excavations, ceramics were obtained, which, together with the lifting material and other data, make it possible to date the canal to the 7th-9th centuries.
The source of the irrigation system Altyn-Aryk was found 2 km south-east of the modern settlement. Kzyl-Tu, Kyzyl-Kum district, Chimkent region on the bank of the river Arys. River water was taken into the irrigation network with the help of two head devices. From their connection, a diversion channel departed, through which excess floodwaters were discharged back into the river. Three more collectors provided water discharge throughout the entire route of the main canal. Its average width along the outer base is 45 cm, the width between the ramparts is 14 m, the height of the ramparts is 3 m, and the length is 30 km. A well-preserved protective dam protected the head section from destruction during the river's floods. A ceramic device was unearthed to drain water into a shallow irrigation network in one of the trenches laid along the canal route. The results of a survey of the Altyn-Aryk irrigation system allow us to date the time of its existence from the 10th to the middle of the 13th century.
The head section of the Karakunchuk irrigation system is located 3 km upstream from the source of the previous system. The head building has not been preserved. The empty part of the main canal and the remains of distributors near Otrar are relatively well traced on the ground. The Karakunchuk system is similar in shape and size to the Altyn-Aryk canals. Pottery dates it to the 13th-14th centuries.
The source of the Timur-Aryk highway was fixed 15 km upstream from the Karakunchuk system. The length of the idle run of water in the canal is 10 km. The width of the head part along the base is 65 m, the width between the shafts is 20, the height of the shafts is 7 m. The total length of the main canal is over 40 km. The command area is 600 square meters. Even today, this grandiose hydraulic structure makes an impressive impression. The time of its construction and operation is the second half of the 14th-16th centuries.
The irrigation canals of the left bank (the territory of the state farm "Sheep breeder" of the Kzyl-Kum district) are identical to the canals of Otrar of the pre-Mongolian period. Nine different-time head canals were recorded here, spaced from each other up the river. The study of the hydraulic structures of the Oasis gives grounds to speak of artificial irrigation in this area from the 7th to the 14th centuries.