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Photo from U.S. Geological Fact Sheet 168-97

Picture 5.

Figure 5.  Discharge waves move downstream faster than the water. For example, in May 1991, the discharge waves produced by rapidly changing dam releases moved through the canyon in about 12/3 days, whereas the water took about 41/3 days to travel the 235 miles from Lees Ferry to Gneiss Canyon. The dye was injected at Lees Ferry into the discharge wave labeled wave 1 (top graph). Wave 1 passed the Gneiss Canyon sampling location on May 8, whereas the dyed water passed that location late on May 10.

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