Understanding Lake Lanier’s level
The level for Lake Lanier is measured by distance above sea level. In a normal summer, the lake is at 1071 feet.
Right now its sitting at about 1056 feet. If it gets down to 1035 feet, the water outflow essentially stops and we’re in big trouble. Right now its dropping by about 1.4 feet per week, which puts it below 1035 in late January unless we get some help from congress (or a lot of rain).
Of course, the pace of the dropping water level could increase as it gets lower (1.5 feet/week, then 1.6 feet/week, etc). The reason for the potential increased drop is simply mathematical - if you have less surface area but you are still pulling out the same amount of water each day (~500 million gallons), the level will drop more quickly.
For example, imagine going to your local swimming pool and taking out a large bucketful of water. The level of the pool will drop, but not noticeably — probably less than an inch. Take that same bucket and use it on a kiddie pool and it’ll drop by at least a couple inches, even though you took out the same amount of water.
The same theory applies here. As the lake level drops and you have less surface area, the level of the lake will drop more quickly as water keeps coming out. Fortunately, the reverse holds true — as the lake gets lower, it will require less rainwater to increase the depth.
If any of that was confusing, or if I was wrong in some of my math, please let me know in the comments section below.



















October 20th, 2007 at 6:03 pm
[...] 475 days). The problem is that most of the water is hard to get to. Once the level of the lake drops below 1035 feet it becomes much more difficult to get the water out (we’ll need barges and [...]
October 29th, 2007 at 11:32 am
[...] been widely reported that Lake Lanier is dropping 1.4-1.5 feet every week (we even said so). After I saw that number posted again while watching “Georgia’s Water Crisis” [...]
October 31st, 2007 at 2:35 pm
These building contractors need to realize you cannot build that many new homes and expect to sustain the water supply. It cannot be “build first, and worry about water shortages later.” I can’t believe Atlanta city officials have allowed this “out of control” growth without wondering how they were going to take care of all the new homes being built. What good is all that property tax if no one has water? I have seen this water crisis coming for years. I knew all it would take was one dry summer and we would have a major crisis. Sad reality is now it may be too late to solve the problem. I pray for rain everyday in Atlanta and its surrounding areas. This problem could easily cause a chaos Atlanta has never seen before if we don’t get some rain soon or adjust water taps to slow the flow rate.
Concerned resident.
October 31st, 2007 at 6:56 pm
[...] are really two parts to this question. First, how long until we hit the 1035 foot mark in Lake Lanier? When that happens, water will no longer flow over Buford Dam. From there, we’ll need to use [...]
November 6th, 2007 at 5:06 pm
[...] you are confused about why the drop will accelerate as the lake gets lower, you can read our “Understanding Lake Lanier’s Level” post from a few weeks [...]
November 21st, 2007 at 10:49 pm
The current Georgia Governor refuses to admit that the current ‘crisis’ has ANYTHING to do with runaway growth. Thank God he’s ‘gone’ with the next election. Politics aside, the future viability of this sector of the United States resides as much with climactic forecasts as with the mental conditioning of the 5+ million residents clinging to the side of an eroding mountain chain deviod of undergound aquifers. In normal rainfall patterns (the ones that sustain the two streams that flow into rivers and together create Lake Lanier), there has not been, is not, & will not be enough water to sustain the currrent growth of the region; any climactic ‘abberation’ in those rainfall pattterns that creates a multiyear deficit could well be a catalyst for the first MASS EXODUS of millions of inhabitants in AMERICAN HISTORY. I hate to say this, but the coming recession & the economic (and building/growth) slowdown that will accompany it is sorely needed to slow the pressures upon the small reservoir named Lake Sidney Lanier, that formerly resided at 1071 feet above mean sea level
December 5th, 2007 at 1:56 am
I believe it may be possible to turn this drought around.
December 6th, 2007 at 7:42 am
The other possible problem that no one (that I can see) has mentioned is what happens if all of a sudden there is quick massive rainfall? With the ground dried and probably weakened, could there be devastating flash floods? Just a thought.
December 10th, 2007 at 7:10 pm
Drought?
Read all about it in The Economist
http://www.economist.com/world/displaystory.cfm?story_id=9071007
December 12th, 2007 at 10:16 pm
The is many reason for the drought. It’s a big issue on T.V. but not a big issue to the people making money from the water. I have a leaking water meter that has been obviously been leaking for over 6 months according to the bill. I found the leak 2.5 weeks ago and reported to Atlanta water dept. They have yet to come out to fix my water problem. In my home there are 2 grown ups and 1 newborn and I used over 19,000 gallons of water last month alone. That’s 3 times the norm and no one has bothered to fix. I have been over average for way over 6 months and the meter person did not report that my meter has water in it everytime they come out to do a meter read. Act on all the broken meter and leaks if you really wanna curve the rate of water consumption. There are reports that shows 40% of meters in meto Atlanta are damaged and leaking. Fix the darn problem. Even if it requires over time. Fix the problems. This is one of the best measures to conserve the remaining of the water we have and this is something the city of Atlanta has control over.
December 15th, 2007 at 6:46 pm
Paul, I have been screaming this since June. And, I don’t even live in Atlanta. I live in South Georgia. I don’t want to see the Atlanta exodus. But, we both know it is coming. I have been in Newspapers, radio, tv and personal appearances, even with elected officials from the State, and members of the State’s “Think Tank”. I offered them the solution to the impending doom of Lake Lanier three months ago, when there was time. At that time, I gave them a cutoff date of December 15th for anything effective to be done. Now it is time for the people of Atlanta to start looking for new homes, if they haven’t already. The State Government of Georgia and the Atlanta City Government already have in place plans to keep the political system rolling. They will truck in water. Once everyone leaves and quits using water, and the rains come and the snow melts, the water will return to the lakes.
February 21st, 2008 at 4:42 pm
This may be an ignorant question, but how much rainfall translates into the water level in Lake Lanier? In other words, if we get one inch of rain, does this equate to one more inch of water in Lake Lanier? Or, does one inch of produce more than one inch of elevation in water level since the streams that feed it also rise, so there compounding effect?
If anyone could provide some insight I would greatly appreciate it.
February 21st, 2008 at 4:47 pm
This post should help answer that.
http://www.atlantawatershortage.com/20071022/what-would-one-inch-of-rain-do-for-lake-lanier/