From 1968 to 1980, the National Marine Fisheries Service (NMFS) conductednumerous transportation studies at Snake and Columbia River dams operated by the U.S. ArmyCorps of Engineers (COE) (Park 1986). Reaulta of these studies were very encouraging for fall(subyearling) Chinook salmon (Oncorhychus tshawytscha) and ateelhead (O. mykiss) in all studyyears, but marginal at best for yearling spring/summer Chinook salmon since 1976. Baaed onresults from 1968 to 1975, mass transportation of smolts around dams has been used in eachsubsequent year in varying degrees, depending upon environmental conditions, as amanagement option to enhance survival of downstream migrating juvenile salmonids.In 1989, NMFS and COE continued to emulate the effect of collection and transportation onjuvenile salmonids dams on the Columbia and Snake Rivera. This evaluation included thefollowing objectives: 1) to mark the transport and control groups of spring/summer Chinooksalmon and steelhead at Lower Granite Dam, 2) to continue the recovery of adult salmonidstagged as juveniles at Lower Granite and McNary Dams for transport research and ideapurposes, 3) to conduct a pilot study of the feasibility of utilizing passive integrated transponder(PIT) tap to evaluate transportation of wild spring/summer Chinook salmon, and 4) to developand evaluate a system to efficiently divert PIT-tagged smolts from the collection system back tothe river at Lower Granite Dam.