Seite - 659 - in Book of Full Papers - Symposium Hydro Engineering

to achieve. Therefore the location design and layout of project design as shown in Fig. 4 was optimized compared with design of feasibility report whereby the dam was located just downstream of confluence of Bann Nullah and Poonch River and a 3.1 KM tunnel located 1 KM upstream in Bann Nullah from its confluence with Poonch River. The Normal Operating Level (NOL) of the project was changed to be at an elevation of 532 meters from the sea level which was modified from 540 meters in the original plan to reduce environmental and social impacts. Fig. 4 Change of Project Design The scheme was changed in order to get following environmental and social benefits:  Under Feasibility Design, approximately 6.1 km of the River would have experienced the low flows due to operation of the Project while in the revised design only 0.7 km of the River will be affected by these low flows. From an ecological standpoint, the negative impact on the ecological resources of the Poonch River will be much less for the changed design compared with feasibility design.  During the breeding season, Golden Mahaseer migrates into the tributaries (nullahs) of the Poonch River for spawning including the Bann Nullah and Rangar Nullah as shown in Fig. 5. The construction of a dam, as envisaged in Feasibility Study, at the confluence of Poonch River and the Ban Nullah would disrupt this breeding migration and negatively impact the population of the Golden Mahaseer. Under the new design, the Project facilities will be located about 6 km downstream of Feasibility Study location. The breeding grounds of Golden Mahaseer particularly in the Ban Nullah will not be directly affected by project operations under new scheme. 659