A politcian with swamp land to sell. Strom has a smile on his face as well.
The National Weather Service will adjust by 1 foot the stage at which the Savannah River officially floods.
Effective Feb. 15, the official flood stage at the confluence of Butler Creek and the Savannah River -- used by forecasters to document floods -- will be raised from 21 feet to 22 feet, according to National Weather Service hydrologist Greg Lamberty.
The change, he said, doesn't mean it will take more water moving down the river to be classified as a flood.
Rather, he said, it is a technical adjustment made necessary by the U.S. Geologic Survey's recent recalculation of the elevation of the bottom of the river channel.
The old zero datum -- or the elevation used as a baseline to calculate rises in water level -- was 96.58 feet above sea level. The previous flood stage was always 21 feet above that mark, meaning flood stage occurred when the water level reached 117.58.
The Geologic Survey's new datum is 1 foot lower -- or 95.58. Thus, to compensate for the change to continue to have flood stage occur at 117.58, the number of feet above the datum was raised a foot, to 22 feet.
"To compensate, you have to increase flood stage by 1 foot to get the same level as it was before," Mr. Lamberty said. "The public needs to know that, because it doesn't flood at 21 feet anymore using the new datum."
The change will not impact federal floodplain elevations or development, he said, but was necessary to ensure accurate flood and river forecasting.
In the past, changes in those floodplain designations helped open more land along the river for development, particularly in North Augusta.
In the 1980s, consultants hired by former Georgia Gov. Carl Sanders claimed that data used to calculate floodplain levels on the river was flawed and unfairly restricted private property and limited its potential.
Federal authorities -- including the Federal Emergency Management Agency -- resisted the request for changes. But after six years, a compromise reached in 1994 altered floodplain levels 8 feet, opening the way for development on Mr. Sanders' 220-acre property, which has since been developed as RiverNorth subdivision.
Reach Rob Pavey at 868-1222, ext. 119 or rob.pavey@augustachronicle.com.
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