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Erosion shrank Applegate Lake in 1997 New Year's Day flooding Applegate Lake has gotten smaller. That's what the Army Corps of Engineers found after an extensive acoustical survey last summer of the reservoir behind the Applegate Dam. "The change was on the order of less than 10 percent change since the project was built, but we don't know how much of that was due to infill in the lake and how much was to do with differing survey methods," said Russ Davidson, who manages the dam from the Corps' Portland office. When the dam was designed, the Corps worked off topographic maps and came up with an original estimate of 82,200 acre feet. But after serious erosion caused by the 1997 New Year's Day Flood, the Corps decided to take another look. "When we toured the empty lake, we saw some large erosion cutbanks there in the lake," Davidson said. And some boat ramps were ankle-deep in mud. Last summer's acoustical survey measured the lake's actual depths. "We took many, many, many soundings a few feet apart all over the entire lake when the lake was full," Davidson said. When more funding becomes available, the Corps will take the next step and calculate what impact, if any, the reduced reservoir size would have on the dam's ability to hold back flood waters. With a change of less than 10 percent, Davidson expects only a few more inches of water would be sent downriver in the event of a flood. Lost Creek Lake wasn't surveyed, he said, because the 1997 flood didn't cause much erosion on the Upper Rogue. Mail Tribune Copyright � The Mail Tribune 1998, Medford, Oregon USA