Sedimentation Study of Kishenganga Reservoir, India

Client: National Engineering Services Pakistan, Ltd.

Contract Period: 2010

The Kishenganga hydroelectric facility is configured as a hydrologically small reservoir with an initial gross capacity of 18.5 Mm3, equivalent to a Capacity:Inflow (C:I) ratio of 0.0062. Of this, the design live pool proposed by India has an initial volume (prior to sedimentation) of 7.55 Mm3. The facility is designed to divert 58.4 m3/s through a 24 km tunnel, generating 666 m of head, delivering water to a 330 MW power station at its terminus which will discharge into the Jhelum River.

Sedimentation aspects of the proposed Kishenganga reservoir were simulated using the SRH-1D numerical model. A projection was prepared of future sedimentation for the reservoir using different outlet structure configurations. Sediment flushing was analyzed as a measure to control sedimentation. Results from the model reveal that the sedimentation in the reservoir will stabilize in the next 30 years, with the configuration dependent on the outlet configuration.

Three alternative reservoir configurations were tested by sediment transport modeling to predict the time required to fill, the equilibrium sediment profile, and grain size of the material transported at the dam.

The Bureau of Reclamation sediment transport model SRH-1D (Sedimentation and River Hydraulics – One Dimension) was used to simulate sedimentation patterns in Kishen-ganga reservoir. Three sediment transport models were prepared to analyze the sedimentation patterns along the Kishenganga Reservoir. Sedimentation patterns for all models were projected for a period of 100 years, a period long enough to reach quasi-equilibrium conditions. The 100-year inflow dataset was prepared by repeating the 32-year inflow dataset, and each model was run for a period of 100 years.