The water level at Lake Lanier will be lower for July 4 than it has been on Independence Day since it was built in the 1950s.

With stumps and sandbars lurking just below the lake's surface, the federal agency that operates the lake issued a warning to holiday revelers to beware.

Michael Lapina, Lanier's chief park ranger with the U.S. Army Corps of Engineers, said all the public swim areas are dry. With buoys marking swim areas on the ground, swimmers are venturing into water where the bottom can drop suddenly.

"That's a potential accident because some people don't know how to swim or they aren't very good swimmers," Lapina said.

In May, a 22-year-old man drowned at Van Pugh North, one of the corps' day-use parks on the southern end of the lake. Lapina said it may have happened when the man stepped off a drop-off.

Some boaters have damaged their motors on the changing lake, he said.

Lanier is nearly 15 feet below full, at an elevation of 1,056.2 feet above sea level. The current record low for July 4 was set during another bad drought in 1988, at 1,061.2 feet above sea level or 5 feet higher than it will be this year.

About 6,500 acres that were once under water are now dry, or about 18 percent of the lake's surface.

According to the corps, only two of 39 public docks are usable, and only 12 of more than 100 lanes at public boat ramps are usable.

The corps expects Lanier to drop another foot by July 25.

Lake Allatoona, metro Atlanta's other popular corps-operated lake for fishing, swimming and boating, is in much better shape. That lake, northwest of Atlanta, is less than 2 feet below its full level.

To find out which boat ramps are still open, go to http://lanier.sam.usace.army.mil/ParkSchedule.htm.

 DALE E. DODSON / Staff 
LAKE LANIER 
This year's Fourth of July level will be recorded as the lowest for the holiday. Holiday elevations are shown in feet above sea level. 
Line graph shows Lake Lanier elevations in feet above sea level from shortly after '57 to current. Graph also indicates when the lake has been full.
Previous low: 1,061.2 
Current: 1,056.2*
Note: Lake began filling in 1956 and did not reach its full pool until 1959. 
*Estimated 
Source: U.S. Army Corps of Engineers