Grant County PUD engineers and mechanics are installing new advanced turbines at Wanapum Dam.  Grant PUD mechanics have extensive experience overhauling turbine units.  After assisting Voith Hydro crews during assembly of the first unit they are managing the assembly of additional units at a good pace.

The new turbine design is the result of a decade of research and testing aimed at learning how dam operators can achieve higher survival rates for juvenile fish passing through turbines. Tests were conducted on the new turbine in the spring of 2005, comparing salmon smolt survival through the new turbine unit and comparing it to survival through an existing unit. Test results revealed an overall weighted survival estimate of 97.82 percent for smolts passing through the new turbine compared to survival rate of 97.71 percent in the existing turbine. Based on the improvement of an already high survival rate, the Federal Energy Regulatory Commission (FERC) approved Grant PUD’s request to continue installing the new turbine designs in remaining generating units at Wanapum Dam.

The new turbine has an added advantage of increasing power output of the turbine by 14 percent and water use efficiency by an average of 3 percent.  When all 10 turbines are replaced, power production will increase by 14 to 20 percent while continuing to provide safe downstream passage of juvenile salmon.