Winter water level drop

[alldodge]

Hear folks mention about how low their water level is dropped in the winter. The ones which get my attention are the 12 to 18 inch drop. In my area Cumberland drops around 20 feet and Dale Hollow drops 10 feet. These are averages because they have dropped more when water is needed for navigation in the rivers.

How far down is the lake where you boat drop?

 

[ahicks]

Our lake does the 12"-18" drop typically, but not always. It depends on rainfall. If we have a real wet end of summer/fall, it drops very little. When the weather has been dry, we'll see every bit of an 18" drop, maybe more, which is bad news for people not paying attention when it comes time to store their boats for the winter. Doesn't happen often, but they could be sitting on the bottom, or on lifts that won't can't drop far enough to float the boat off the lift! Important as winter ice destruction near certain for the boat, and the lift....

High water can also occur, but we do have lake level control via a dam on the outlet side of the lake. Inlet via several springs and the headwaters of a small river that starts in some hills just north and west of the lake.

 

[oldjeep]

Doesn't vary by more than a few inches, but it is actually a lake not a man made reservoir

 

[alldodge]

Wife is from French Lick IN and Patoka was built for flood control as most lakes operated by the Corps. She remembers it was suppose to take a few years to fill and it filled in one year. Patoka drops about a foot also and then you see stumps and islands expose themselves. For Dale to start showing submerged islands it has to drop several feet and the lake is deep, many areas over 100 foot

 

[QBhoy]

Loch Lomond actually rises. Currently it's about 4-5ft deeper than the summer peak (if there is such a thing in Scotland).
Probably caused by the fact it's a resovoir for large pet of Scotland (and England when required). The level is controlled by Scottish water by means of a dam at the exit point to the sea.

 

[alldodge]

There are some dam's which are only used for water supply, and this sounds like the one you mentioned. The ones controlled by the US Army Corps of Engineers (USACoE) are used mainly for flood control. This is why they lower the level in the winter so they can catch and hold the water later when rains come. Here in Kentucky the Cumberland River fills Lake Cumberland (LC). Wolf Creek dam holds the water for LC and releases water blow the dam into the Cumberland River (CR).

The Obey and Wolf rivers fill Dale Hollow Lake an the Dale Hollow dam empties into the low Obey river which ends in the CR. The J.Percy Priest and Center Hill dam's are in Tennessee are used to hold the waters of Caney Fork and Falling Water rivers, which intern empty into the CR. The USACoE controls the water flow for flood and commercial barge traffic in the CR and as it passes through.

The Corps order of priority is
Flood control
Commercial traffic
Water supply
Recreation

 

[NYBo]

Mine has been rising. If last winter was typical, it will rise about 6" more or thereabouts.

 

[southkogs]

Priest hasn't gone down as of yet, and the drop is usually less dramatic than Dale Hollow or Center Hill would be. But, we'll drop an easy 8 to 10 feet. I haven't watched Nickajack all that closely, but I know they drop that one too.

 

[jkust]

The lake level that our house is on is managed by the Army Corp of Engineers all year long. The do a winter draw down to deal with whatever the snow fall is that winter to account for the spring thaw and spring rain. Maybe a foot of elevation difference or thereabout.

 

[fishrdan]

I usually boat/fish on Lake Mohave, and every October they draw down the lake 10' for maintenance (endangered species - suckers). By November the lake is back to it's normal level. This lake is on the Colorado river, so they manipulate the flow rates, in-out, to raise and lower the lake.

 

[trailking82]

I was surprised when i found out some lakes here only drop a foot or two for winter pool. I know my main lake drops 35 foot for winter pool. Where as the lake closer to me only drops about a foot or two. I thought they all dropped a great deal for flood protection.

 

[alldodge]

I thought they all dropped a great deal for flood protection.

Most do drop for flood control and the distance (I think) is based on how deep the lake is. Exp: Cumberland max depth is 197 feet, Dale max depth is 130 feet, where as Patoka is 52 feet

 

[southkogs]

I know that the draw down on the lake level is typically to a specific elevation above mean sea level. For Priest, summer pool is right at 490ft MSL. They draw down in winter to 483ft MSL. One would think the drop would look like a simple 7' lowering, but honestly it seems to fluctuate. Part of that is from flow, but I don't know what else comes into play.

 

[jkust]

I was surprised when i found out some lakes here only drop a foot or two for winter pool. I know my main lake drops 35 foot for winter pool. Where as the lake closer to me only drops about a foot or two. I thought they all dropped a great deal for flood protection.

One issue on our lake is that they won't draw down in advance of an anticipated once in 100 year type storm in the even that the rain doesn't actually fall. We had our one in a 100 years event about 5 years ago.