Inflow to Lanier reaching record lows
The various rivers and streams that flow into Lake Lanier are at (or near) their all-time lows, which isn’t a good sign for the lake.
According to 11Alive, the Chattahoochee River north of the lake is at 28% of its normal flow. Other than the 28% figure, the article didn’t give any other numbers, just quotes from local residents talking about how low it looks.
So far this year, the lake has done pretty well. It even surprised some folks (like myself) when it rose a few inchdes last month. This month has been a slow but steady drop, down about 4 inches so far. Last June, the lake dropped by about 21 inches, so at least we’re still dropping at a slower rate. Of course, we’re already about 10 feet lower than this time last year…
If the inflow continues to dwindle, this could create some big problems, even with the revised operating plan in place.
Tags: chattahoochee, inflow, Lanier, operating plan
June 14th, 2008 at 5:33 am
BIG PROBLEMS?
[shudder]
DEAD POOL?
BGGAAAAWWWKKKKKKKKK
June 14th, 2008 at 7:32 pm
The year to date total inflow (through June 13) is the third lowest in Lanier history. Even 2007 had a better total inflow over the same period (14.3% better).
Afternoon pop-up thunderstorms like the ones we’ve been getting may help to keep some lawns green but they won’t have a significant impact on Lanier inflow. This is because soil moisture and groundwater levels in the Lanier drainage basin are so low that most of the rain that doesn’t fall directly into the lake never makes it to the lake.
Even so, Atlanta will be just fine this year as long as the US Army Corps of Engineers doesn’t open the flood gates again this summer in its misguided and arguably illegal policy to support an obscenely inefficient Florida power plant and “endangered” Florida mussels of dubious environmental import.
As a drought-busting weather pattern shift this year seems increasingly unlikely, the best hope for a Lanier recharge is to have a tropical storm or two come marching up out of the Gulf and dump copious quantities of rain over the Lanier drainage basin. As oil speculators are happy to use any excuse to run up the price of crude, however, a tropical storm or a former hurricane that comes our way via the Gulf could well prove to be both a blessing and a curse.
– DSO –
June 16th, 2008 at 8:56 am
June so far:
Average loss of 0.0319 feet / day
Total loss of 0.51 feet
Average loss of 1.06 thousand acre-feet of storage/day
Total loss of 17 thousand acre-feet of storage.
We’re 6.36 feet above the low point in depth for the lake. If we kept at this average loss, it would take 200 days to reach that point.
June 17th, 2008 at 11:17 am
200 days?
We’re -146 days from dead pool already!
BGAAAAWKWKKKWKKWKWKWKK!
June 19th, 2008 at 8:43 am
I’ll update the predictions page at the end of June. With less than 30 days data, a single day can make a big difference. For example, NOW june so far:
Average loss of 0.0379 feet/day
Total loss of 0.72 feet
Average loss of 1.26 thousand acre-feeet of storage/day
Total loss of 24 thousand acre-feet of storage.
We’re 6.15 feet above the low point from last year. At this rate of average loss, it would take 162 days (11/28/2008) to reach that point this year.
June 19th, 2008 at 9:23 am
The Lake starts filling up November or December so it’s touch and go so far, unless we get that big tropical storm of course.
rkolter, remind me again, are you included a surface area as a function of depth profile, or assuming it’s constant? Thanks.
June 20th, 2008 at 9:11 am
I do not include surface area as a function of depth profile. This means that my predictions are always optimistic. With a constant outflow, the surface area of the lake will decline, leading to faster drops in depth as the lake drains. I have a chart covering that based on the way the lake filled - it closely match the ACE predictions on the decline in water depth that are based on surface area.
For the next six feet of depth though, we have a good idea what will happen to the surface area, and the loss of surface area means less. The first real precipitous(sp) drop-off should be in the high 1040’s. That’s when the lake started to really flood surface area as it filled, and when it will really withdraw quickly as it drains.
A far more accurate predictor overall is the volume predictor.
As for it refilling in November and December… it only does that when it’s not in a drought… it sure didn’t fill back up last year during those months. Forget that tropical storm stuff. Get a bucket brigade going - St. Louis would be thrilled to death to give you a few billion gallons right about now.
June 21st, 2008 at 4:54 pm
I’m working on the assumption that the immediate drought is due to the El Nino/La Nina SST oscillation that usually lasts about two years. Also, by November and December I meant that then is when then lake stops declining, I didn’t mean that it refilled completely.