Numerical simulation of Eutrophication in dam reservoirs using CE-QUAL-W2 software (Case study:Baft dam)

Subject Areas : Subjects

m. ابراهیمی ¹ (دانش‌آموخته‌ی کارشناسی‌ارشد سازه‌های هیدرولیکی دانشگاه قم)
e. جباری ² (استادیار گروه مهندسی عمران دانشگاه قم)
h. عباسی ³ (دانشجوی دکتری تکنولوژی محیط‌زیست دانشگاه گنت بلژیک)

Received: 2014-09-13 Accepted : 2014-09-13 Published : 2014-05-22

Keywords: Eutrophication, Baft dam, CE-QUAL-W2 software,

Abstract :

Eutrophication is one of the most important problems which affect quality of the reserved waters in dams.In this research, using CE-QUAL-W2 software in three states of low water, normal and high water, water quality condition of Baft dam reservoir was measured in terms of monthly changes in phosphate and nitrate. Although the results of the simulation indicate low concentration of phosphate and nitrate in the Baft dam reservoir, these low concentrations given the different eutrophication indices (Chapra Index, Meybeck Index, Carelson Index, and Vollenweider diagram) places Baft dam reservoir in the nutritive area. In addition, in terms of nitrate concentration, Baft dam reservoir is positioned in the interstitial area. And in terms of drinking and agricultural consumptions, the Baft dam reservoir has no problem, yet finding a solution to prevent the Baft dam reservoir from entering the nutritive area which may strongly affect the water quality is necessary. Considering the thermal stratification peak in late August and start of the dam reservoir mixing in February, for preventing the Baft dam reservoir from entering the extremely nutritive area, some suitable solutions can be proposed including: reducing water stay in the dam by quick impoundment from lower layers in late August and impoundment from the lower layers in late December, preventing entry of rural sewages and agricultural waters from upstream of the Baft dam reservoir.