Abstract: In the Pacific Northwest, downstream migration of juvenile salmon on the Columbia River has been impeded since 1933 by the construction of 14 hydropower facilities. Volitional passage of juvenile fish through turbines at these facilities has resulted in direct mortality and indirect mortality from the effects of dams on the surrounding environment. For over three decades, improving fish passage has been a high priority on the mid-Columbia River by the Public Utility District of Grant County. Two unique bypass systems have been designed, built, and installed over the past six years to improve fish passage at Wanapum Dam (2008) and the Priest Rapids Dam (2014). Since 2008, fish passage efficiency studies using acoustic and passive integrated transponder (PIT) systems have shown annual variability at both dams. At Wanapum Dam, up to 77% of the juvenile steelhead passed through the bypass system, which is equal to a 66% reduction in turbine passage; the average between 2008 and 2010 was 71%. At Priest Rapids Dam, results from 2014 have demonstrated that a total of 69% of juvenile steelhead passed through the top-spill bypass and spillway, which was a 19% increase in the average non-turbine passage from previous estimates (2008- 2010). This case study will be presented to highlight the telemetry tools that were used to evaluate the spring migrants that used downstream passage alternatives in the mid-Columbia River during these studies. The results, fish passage behavior, guidance efficiency, and survival at both dams and the associated reservoirs before and after the installation of both bypass systems, will be discussed.