If you have a boat in Lake Lanier now, you might want to consider taking it out for the winter while you still can.  According to sources from the Corps of Engineers, there are currently only nine boat ramps still open on Lake Lanier.  At the current forecasted rate of decline, the number will dwindle to only one by the middle of November, and zero by December 10th. 

The US army Corps of Engineers publishes an excel spreadsheet that calculates and predicts the status of all 106 ramps on the lake, and according to this spreadsheet, at the current level, only nine are open.

By contrast, Lake Hartwell is also down over 10 feet, but over half of its 97 ramps are still useable.  On December 10th, according to forecasts, there will be no useable ramps on Lake Lanier at all.  Lake Hartwell will have 46.

Data Sources:

Lanier Ramp Data
http://lanier.sam.usace.army.mil/BoatRampElevations.htm

Lanier Level Forecasts
http://water.sam.usace.army.mil/fc.htm

Lanier Level Forecast Graph
http://water.sam.usace.army.mil/lanfc.htm

Hartwell Ramp Data
http://www.sas.usace.army.mil/lakes/hartwell/hartrampelev.doc

Hartwell Level Graph
http://water.sas.usace.army.mil/archive/10Week/071029_P004.gif