At the direction of KWUA, Dave Vogel, a fisheries biologist with 28 years of experience, examined and compared the maximum water temperatures during September 2002 immediately below Iron Gate Dam on the Klamath River, on the Trinity River below Lewiston Dam, and in the area of the fish die-off. Key aspects of Vogel’s findings include:

• Unlike the upper Klamath River during September, the Trinity River does have cold water suitable for salmon.

• Vogel’s recent study examined and compared the maximum water temperatures during September 2002 at the following three locations: 1) the Klamath River downstream of Iron Gate Dam, 2) the Trinity River downstream of Lewiston Dam, and 3) the lower Klamath River at river mile 6 in the area of the fish die-off.

• Although water temperatures downstream of Iron Gate Dam were as warm or warmer than the area of the fish die-off during most of September, Vogel determined that water temperatures in the upper Trinity River were much cooler and within the suitable, if not optimal, range for salmon.

• The significance of this fact is that, prior to the time of the fish die-off in the lower Klamath River, water temperatures were hostile for salmon in the main stem downstream of Iron Gate Dam, whereas temperatures in the main stem Trinity River downstream of Lewiston Dam were suitable for salmon.

• Increased Iron Gate Dam releases could not have cooled down the upper main stem Klamath River but increased Lewiston Dam releases undoubtedly could have cooled down at least a portion of the main stem Trinity River downstream of Lewiston Dam providing thermal refuge for salmon in that area of the basin.