Thursday, May 29, 2008


With very high snowfall this year - record levels at some locations - the threat of snowmelt flooding has been a concern. There is still 9 feet (2.75 meters) of snow at 5,000 feet (1524 meters) on Mount Hood. At 6,000 feet (1829 meters) near Timberline Lodge there is nearly 14 feet (4.25 meters). This is more on the ground that falls many years.

In April 2002 we had heavy rains combined with melting snowpack to produce a moderate flood, perhaps 37 or 38 feet (11 meters) above sea level, or about 15 feet (4.6 meters) above the rivers summer levels. The peak lasted less than a day.

This year, despite continual cool wet weather, no large rain events have come along. A 5-day heat wave starting May 15th gave local highs from 84 to 95 (29 to 35 Celsius) and began rapid snowmelt. Since then the river has kept at 28 to 31 feet (9 meters) above sea level with the continuing meltoff at high elevations. No dramatic flooding is happening, but the sustained high levels are unique in our 20 years living on the banks of the Clackamas.

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