Tarbela dam loses over 40% storage capacity due to silting
ISLAMABAD: A per Hydrographic Survey 2017, water storage capacity of Tarbela Dam has reduced by over 40 per cent due to silting in the reservoir.
“As per results of Hydro graphic Survey 2017 of Tarbela reservoir, since operation the live and gross storage capacities of Tarbela reservoir have reduced by 37.524% and 40.58% respectively,” sources told APP here.
They said inflow of sediment is a natural phenomenon and cannot be prevented. However, construction of Diamer Bhasha Dam will help reduce the inflow of silt into Tarbela Dam. Diamer Bhasha dam will enhance the life of Tarbela dam up to 35 years, they said. They said WAPDA had conducted sedimentation studies in the years 1987, 1991, 1997, 1998, 1999, 2007, 2013 and 2014 for evaluation of possibilities of de-silting Tarbela reservoir.
Quoting studies they said, sediment flushing is uneconomical, technically risky, impacts on the existing infrastructure would be overwhelming resulting into increased variation in bed profile of downstream river system will impact on barrage operations with increased sediment entering the canals. Additionally, it would accompany the loss of electricity generation at Tarbela and Ghazi Barotha besides the loss of water storage for the irrigation purpose. - APP