Army Corps of Engineers Says Voids Do Help.
May 02, 2008 - MATTHEW EISLEY, Staff Writer

Q: Why is the Corps of Engineers releasing water from the Falls Lake dam? Shouldn't they be saving it for summer?
-- Wayne Alexander, Raleigh

A: With memories of Falls Lake's long drought-induced depletion still fresh, it seems obvious to many people that the U.S. Army Corps of Engineers should let Raleigh's water supply source swell higher than normal, before summer's heat evaporates much of it and the city's water consumption soars.
Raleigh Mayor Charles Meeker and other city officials want the corps to let the lake stay 2 feet higher during spring to stave off summer shortages.

But corps officials have been cool to the idea. They note that another of the lake's major purposes is to reduce flooding along the Neuse River, which helps protect downstream property owners and the low-lying towns of Smithfield, Goldsboro, and Kinston.

To do that, Falls Lake's operators have to leave space for water to rise during heavy rains -- about 13 feet is the target. Once the lake reaches its normal elevation of 251.5 feet above sea level, the corps releases about as much water as flows in.

"A major rain event on top of an overfull pool could cause serious problems," corps spokeswoman Penny Schmitt said. "There is so much downstream development and encroachment that we are not able to make big releases out of Falls Lake without causing at least nuisance flooding to neighborhoods downstream."
Therefore, Schmitt said, the corps must try to keep the lake level as close to its target height as possible so that a deluge wouldn't force the agency to release damaging volumes downstream.

The corps will have to operate the lake close to target level, she said, "in spite of public desire for 'drought insurance' in the form of extra stored water."

The 28-mile-long lake north of Raleigh was a foot and a half above full Thursday, so the corps was releasing 510 cubic feet of water per second -- about seven times the rate of Raleigh's water use.

The release is expected to increase today to 750 to 800 cubic feet per second, about 11 times Raleigh's water usage but much less than would cause downstream flooding.