Wednesday, September 23, 2009


Some interesting photos and comments from the U.S. Geological Survey on the recent flooding in Atlanta, with particular regard to conditions right here in my own neighborhood:

Flood conditions at Peachtree Creek on Sept. 21st — stream height (gage height) is about 20 feet, which corresponds to about 9,000 cubic feet of streamflow (cfs) and almost to the level of Northside Drive.

Normal flow conditions at Peachtree Creek. At base flow conditions, gage height is about 3 feet, which corresponds to about 100 cfs. That standpipe thing is the stream gage, where the streamflow measurements are taken.

Historic high-water flood conditions at Peachtree Creek on Sept. 21st — stream height (gage height) is about 23.7 feet, cresting over Northside Drive.

Flooded house on Woodward Way, next to Peachtree Creek at Northside Drive.

And here's a view of Woodward Way, parallel to Peachtree Creek, flooded. But we here in Atlanta actually had it pretty good compared to portions of Georgia to the west of us. Here's a collapsed bridge over Snake Creek in Whitesburg in Carroll County:

When bridges such as this one collapses during a flood, it is more often not the pressure of the rushing water against the bridge structure that causes the bridge to fail. Rather, the rushing water erodes the ground underneath and surrounding the structure that supports the bridge to erode away, and the lack of support under the bridge causes it to collapse.

Here's Sweetwater Creek in Austell in Cobb County:

For sheer devastation, it's hard to top the flooding in Powder Springs Creek near the town of Powder Springs in Cobb County.

Tragically, I learned today that the son of a former co-worker of mine was one of nine who died during this flood - he drowned when the SUV he was driving got swept away by the floodwaters. Apparently, this happened near Powder Springs. not at all far from where the pictures above were taken.

No comments: