Name:	blmeanie -	Reply
Subject:	Lake Allatoona volume drop
Date:	1/12/2018 6:25:46 AM

Every year as the lake level bottoms out around 823' I wonder what the 17' of lake water level is in gallons to take it back to full pool.

Obviously there is shorline creep so it isn't straight 17' down from full pool shore line, but has to be an incredibly staggering amount of water for the lake to add back 17' depth.

With the concerns on water usage and shortfalls in parts of the world always has seemed crazy to purposefully drain that much water out of so many lakes each year.

Name:	JohnnySlalom -	Reply
Subject:	Lake Allatoona volume drop
Date:	9/7/2018 2:21:45 PM

This is a common misconception.  They do not just intentionally drop the lake levels on purpose.  The drop is due simply to the decrease in rain during the fall/winter months coming into the lake from the rivers.  Also, by the end of summer with all the heat, there is even more evaporation.

By law, there has to be a steady flow of water coming out of the dam going downstream.  The amount of water they have going through the dam is constant and only changes when the lake gets too high, when they have to increase the outflow.

So, during the fall and winter, there is less water coming into the lake than the amount going out through the dam.  Ergo, the level steadily drops.  Once the spring rains start, you see the level start rising again.

Name:	Craig -	Reply
Subject:	Lake Allatoona volume drop
Date:	10/1/2021 2:26:30 AM

Allatoona is operated by the Corps of engineers as primarily a flood control lake for the Etowah/Coosa rivers. They purposely drop the lake level 17 feet every Autumn to "allow sufficient capacity for spring floods". Why they need that much of a drawdown I dont know but in the early 60's winter pool was below 820. The COE raised it to 823 in the early 70s'. The other purposes of the lake are hydro power, drinking water, and recreation. Full pool is only allowed for about 5 months of the year. If they waited until the end of November to draw the water down it would extend the season and be much safer for people using the lake. The people who really have it bad are at the very Southern end of the lake in Cobb county where it goes completely dry at 832 elevation.