Study of the Thermal Stratification in NO.1 Zabol Chahnime Reservoir in order to manage the quality of water resources in the plain of Sistan

Water lakes and reservoirs of dams in temperate regions in some seasons due to changes in climatic conditions undergo thermal stratification. This phenomenon can change the qualitative factors of water. Therefore, studying about thermal stratification and its time can provide a suitable pattern for water quality management and even monitoring. This research was carried out with the aim of determining temperature changes at different levels of water and heat model of NO.1 Zabol Chahnime Reservoir for optimal management of this valuable resource.

The descriptive-analytical study was conducted through determining sampling station and monthly water harvesting from 8 different water depths (from the surface to the depth of 15 meters) from October 2015 to October 2016. Along with temperatures, TDS, EC, DO and PH factors were also investigated at different depths of reservoir. Finally, multivariate statistical analysis was used to interpret the data set.

The thermal stratification in NO.1 Zabol Chahnime Reservoir starts early in the spring of May, and lasts for almost 6 months from about every year until early November. This phenomenon is most severe in mid-summer and July. Stratification with the onset of the autumn season is lost due to climate change and the tank is homogeneous.

Qualitative factors of Chah Nimeh No. 1 changed under the influence of thermal stratification in different seasons, but their overall average was appropriate according to global standards; and the reservoir water had a drinkable application. In line with the qualitative management of this reservoir, it should be noted that water harvesting from various water levels provided different qualities in spring and summer, but the water quality at different depths of lake was almost the same in the fall and winter.