Page 326 - Laboratory Manual in Physical Geology

Flood Hazard Mapping, When the water level of a river is below the river’s
banks, the river is at a normal stage . When the water level
Assessment, and Risks
is even with the banks, the river is at bankfull stage . And
The water level and discharge of a river fluctuates from when the water level exceeds (overflows) the banks, the
day to day, week to week, and month to month. These river is at a flood stage .
changes are measured at gaging stations, with a permanent Early in July 1994, Tropical Storm Alberto entered
water-level indicator and recorder. On a typical August day Georgia and remained in a fixed position for several days.
in downtown St. Louis, Missouri, the Mississippi River More than 20 inches of rain fell in west-central Georgia
normally has a discharge of about 130,000 cubic feet of over those three days and caused severe flooding along the
water per second and water levels well below the boat Flint River. Montezuma, Georgia, was one of the towns
docks and concrete levees (retaining walls). However, at the along the Flint River that was flooded, and it is the subject

peak of an historic 1993 flood, the river discharged more of Activity 11.6 . Some of the flood damage experienced by

than a million cubic feet of water per second (8 times the Montezuma, Georgia, in 1994 could have been prevented by
normal amount), swept away docks, and reached water planning ahead.
levels at the very edge of the highest levees.

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