Completion of the Thartar Head Race Canal

The completion of the Thartar Lake Head Race Canal is a critical steps for the use of the lake during very draught years. The design parameters of the Head Race canal are: Length = 1.1 km, Bottom width = 100 m, Bed level = 40.00 m (not implemented). The sill level of the Tharthar outlet Escape regulator = 37.50 m asl (lower than the design headrace bottom level of 40 m asl). According to the original design, a withdrawal of 150 m3 in emergence condition with a level in Tharthar lake of 43.70 m asl is provided. This condition is selected based on the normal level upstream Faluja Barrage (42.50 m asl), since Faluja barrage backwater is impacted by the release from Tharthar, even though in most drought years the upstream Faluja barrage can be lowered to get more water from Tharthar during the exceptional drought year.

During the 1999-2001 drought cycle the water resources management rely mainly on the carry over storage that was available in Tharthar depression at the beginning of the drought period in 1999. After the first year of drought part of the available storage was drawn from the lake so the water level in Tharthar dropped to critical level. The reason for the critical situation was attributed to incomplete construction of the ” Head race Canal ” according to the design, this come very clear when the water level drop to level that was never reached before. At that time, some urgent measure were taken but the Head Race CAnal can was never completed.

Provide secure utilization of the Thartar Storage during dorught periods. Complete the design of the HR Canal based on updated bathymertric survey of the outlet area. Excavate the bottom outlet to reach design conditions. The cost of the work are not high

Governament of Iraq