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Clear Lake Information


What is Rumsey?

The natural level of Clear Lake has been maintained by the Grigsby Riffle, which is a rock sill located at the confluence of Cache and Seigler Creeks near Lower Lake. The natural low water level of Clear Lake was established as "Zero Rumsey" and all subsequent lake measurements are based on this elevation.

Zero Rumsey is equivalent to 1318.256 feet (1929 NGVD).
This file last updated April 13, 2015