Kentucky Lake covers 120,612 acres, and a day on it is mostly a question of which arm you are in. Lake Cumberland and Lake Barkley are each right around 50,000 acres, and water that size has enough fetch that an afternoon wind puts a chop on the main body while the creek arms stay flat. This is reservoir boating. Underneath the lake is a river valley, the deep line follows the channel that was there before the dam went in, and the water to either side of that line is shallower than the middle of it. Anyone who keeps a boat on one of these lakes carries that map in their head. On a lake you have not launched on before, you do not have it.
The Kentucky pack carries 2,364 charted water bodies. Of those, 556 carry a name, and 42 of the named ones are larger than a square kilometer. The outlines come from the National Hydrography Dataset. The depth on them is built from state elevation surveys, because no NOAA chart was ever drawn for a reservoir. That is the whole difference between water you can plan a route across against your own draft and a blue shape with a label on it.
Kentucky Lake is the largest water body in the pack at 488.1 square kilometers, or 120,612 acres measured from the chart polygon itself. Lake Cumberland is next at 50,360 acres, and Lake Barkley after that at 49,223. Those two are within about eleven hundred acres of each other, a difference nobody would register from the helm. Kentucky Lake is nearly two and a half times either one. The three together come to 220,195 acres of charted water.
Below them the pack steps down into a different class of lake. Dale Hollow Lake at 25,402 acres and Norris Lake at 23,178 are the only two in the twenty thousands. The next name under Norris is Reading House Slough at 10,897 acres, which is less than half of it, and the list runs steadily smaller from there. Forty two named lakes in the pack clear a square kilometer, which is roughly the size where a lake stops being water you can read from the ramp.
The named lakes are the smaller part of the count. The pack holds 2,364 water bodies in total, so 1,808 of them are pieces of water the National Hydrography Dataset records without a name. They are on the chart the same as the rest.
| Lake | Charted surface area |
|---|---|
| Kentucky Lake | 488 km² (120,612 acres) |
| Lake Cumberland | 204 km² (50,360 acres) |
| Lake Barkley | 199 km² (49,223 acres) |
| Dale Hollow Lake | 103 km² (25,402 acres) |
| Norris Lake | 94 km² (23,178 acres) |
| Reading House Slough | 44 km² (10,897 acres) |
| Barren River Lake | 38 km² (9,415 acres) |
| Green River Lake | 34 km² (8,402 acres) |
| Cave Run Lake | 33 km² (8,056 acres) |
| Nolin Lake | 24 km² (6,005 acres) |
| Laurel River Lake | 24 km² (5,931 acres) |
| Rough River Lake | 20 km² (5,016 acres) |
The twelve largest named lakes the Kentucky pack carries, by charted surface area, measured from the chart polygon itself. The pack carries 2,364 charted water bodies in all, 556 of them named, and 42 named lakes larger than one square kilometer.
The coast has NOAA charts because somebody surveyed it for ships. A reservoir has nothing of the kind behind it. It was a valley until the dam closed, and no hydrographer was ever sent out to sound it for navigation. That is why a lake shows up in most chart apps as a flat blue fill with a name on top.
Helm builds inland depth from state elevation surveys instead, and takes the water bodies themselves from the National Hydrography Dataset. The outline comes from the dataset, the numbers under it come from the survey, and each reading carries the date it was measured. Kentucky is one of 48 state lake packs put together this way.
What that gets you at the ramp is ordinary chart behavior on water that usually does not have any. Enter your draft once and the water your boat cannot cross shades. Draw a line from the ramp to the far bank and the shallowest point along it is marked rather than averaged in. The machinery behind the shading and the routing is the same everywhere in Helm and is covered on the depth and routes pages.
Summer pool and winter pool are not the same lake. A flood control reservoir gets drawn down and brought back up on a schedule that has nothing to do with your weekend, and on a lake with long shallow coves a foot of pool moves the shoreline a long way back in them.
The shape is the part that holds. The old channel runs where it runs whatever the gauge reads that morning. A flat at the mouth of a cove is a flat at any level. Contours tell you where the bottom falls away and where it stays up, and that relationship survives a change in pool even when the number printed over it has shifted. Late in the year on a drawn down lake, the channel is still the same line, and the shoulders on either side of it are exactly the part worth having shaded against your draft.
People who run these lakes already watch the level. The chart is the piece that does not move with it.
These are the twenty largest names in the pack, in acres measured from the chart polygon.
Several of them are close enough in size to be worth knowing apart. Nolin Lake at 6,005 acres and Laurel River Lake at 5,931 are 74 acres apart. Taylorsville Lake at 2,916 and Herrington Lake at 2,842 happen to be 74 acres apart as well. Barren River Lake at 9,415 acres and Green River Lake at 8,402 trade places in most people's memory, and Cave Run Lake at 8,056 sits just under the pair of them.
Grayson Lake at 1,211 acres is the smallest of these twenty. Another twenty two named lakes in the pack fall below it and still clear a square kilometer, and under those sit the rest of the 2,364.
Inland lake depth comes from state elevation surveys rather than from nautical charts, and a reservoir sits at whatever level it is being held at that week. Treat the shape and the depth as a guide, keep a lookout, and verify locally.
Depth. The outlines come from the National Hydrography Dataset and the depth is built from state elevation surveys, so both lakes carry contours and a depth number on the water itself instead of a flat fill. Kentucky Lake is 120,612 acres at the chart polygon and Lake Barkley is 49,223.
Kentucky Lake is 120,612 acres and Lake Cumberland is 50,360, so nearly two and a half times. Lake Barkley is a little over eleven hundred acres behind Cumberland at 49,223. The three of them together account for 220,195 acres of the water in the pack.
Yes, at 25,402 acres. The packs are cut to a box rather than to a state line, so water near a border can be carried by more than one pack. Norris Lake is in this one too, at 23,178 acres. The neighboring lake pages cover Indiana, Ohio, West Virginia and Virginia.
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