Almost every big lake on this list is a river with a dam at the bottom of it. Guntersville Lake and Wheeler Lake are two pools on the same run of the Tennessee, and the open water you see from the ramp is sitting over a drowned river channel with flooded bottomland on either side of it. Weiss Lake and Logan Martin Lake bend the way the river bent. Lewis Smith Lake runs back into creek arms that keep narrowing until the far end of one is a creek again. Where you can run wide open and where you idle is mostly a question of which part of that old valley is underneath you.
The pack is one download, and it carries 5,530 charted water bodies. Of those, 1,623 have a name on them, and 86 named lakes are larger than a square kilometer. The depth under that water does not come from a nautical chart, because nobody surveys a reservoir the way the coast has been surveyed. It is built from state elevation surveys, and the water bodies themselves come from the National Hydrography Dataset.
Two of those three counts put this pack in the top third of the 48 state lake packs. The 5,530 charted water bodies rank 15th, and the 1,623 named ones rank 15th as well. The third count is the one that only looks at big water: 86 named lakes clear a square kilometer, which ranks 29th.
Read together they describe water that is mostly small. For every named water body in the pack there are more than two carrying no name at all, and those are farm ponds, sloughs, oxbows and the backs of coves. Some of them are worth a morning in a jon boat and none of them will ever appear on a printed chart.
One thing about how the packs are cut. They are cut to a box rather than to a state line, so water close to the Georgia, Tennessee, Mississippi or Florida line ends up inside two boxes and is carried by both downloads. That is why nothing on this page says a lake is the largest in the state. What can honestly be said is which lake is the largest one this pack carries.
| Lake | Charted surface area |
|---|---|
| Guntersville Lake | 264 km² (65,260 acres) |
| Wheeler Lake | 211 km² (52,164 acres) |
| Martin Lake | 162 km² (40,031 acres) |
| Walter F George Reservoir | 141 km² (34,743 acres) |
| Pickwick Lake | 139 km² (34,323 acres) |
| Weiss Lake | 103 km² (25,402 acres) |
| West Point Lake | 90 km² (22,215 acres) |
| Lewis Smith Lake | 79 km² (19,571 acres) |
| Logan Martin Lake | 67 km² (16,605 acres) |
| Wilson Lake | 63 km² (15,469 acres) |
| Lay Lake | 50 km² (12,454 acres) |
| R E 'Bob' Woodruff Reservoir | 47 km² (11,540 acres) |
The twelve largest named lakes the Alabama pack carries, by charted surface area, measured from the chart polygon itself. The pack carries 5,530 charted water bodies in all, 1,623 of them named, and 86 named lakes larger than one square kilometer.
There is no NOAA chart for a reservoir. A lake behind a dam was a valley within living memory, and the survey work that produced coastal charts never happened out there. So inland depth in Helm is built from state elevation surveys instead, with the shape and extent of the water coming from the National Hydrography Dataset. That combination is the entire reason a lake in Helm is charted water rather than a blue shape with a name floating on it. You get contours, a depth figure where you put your finger, and a shallowest point along any line you measure, which is what lets you plan a run across it against the draft of your own boat.
The second thing worth saying about a reservoir is that it sits at whatever level it is being held at. The bottom does not move. The waterline does, over a season and sometimes over a week, so the same contour has a different amount of water over it in February than it had in June. Read a lake contour the way you would read the elevation survey it came from. It is telling you the shape of the ground, and the level the lake is being held at that day tells you how much water is on top of it.
On a pool that has been pulled down, that difference is exactly where people get in trouble. The old river channel is still the old river channel and still runs deep. The shoulder beside it, and the flat at the mouth of a cove, are the parts that quietly come up to meet you.
Guntersville Lake is the largest named lake in the pack at 264.1 square kilometers, or 65,260 acres. Every figure here was measured from the chart polygon itself rather than copied from a published number. Wheeler Lake follows at 211.1 square kilometers. Those two together hold more water surface than the next three on the list combined.
The comparisons are worth sitting with if you only ever fish one of these. Weiss Lake at 102.8 square kilometers and West Point Lake at 89.9 are both serious water by any ordinary standard, and the pair of them together is still smaller than Guntersville on its own. Martin Lake at 162.0 square kilometers is nearly two and a half times Logan Martin Lake at 67.2, which is something you feel in a chop when the wind has fetch to work with. Lake Tuscaloosa at 20.5 square kilometers, 5,066 acres, is a full Saturday of boating and about a thirteenth the size of Guntersville.
Here is the list, largest first.
A tow to Lewis Smith Lake or Weiss Lake ends somewhere with two bars if the morning is going well, so the pack goes onto the phone at home over wifi and stays there. After that the chart, the depth shading, routing, the measure tool and the anchor alarm keep working with nothing in the signal bar.
Enter your draft once and it stays on the chart. The water your boat cannot cross shades, and on a reservoir what shades is the shoulder beside the old channel and the flat across the mouth of a cove. That is the shoal on your screen while you still have room to turn. Draw a line with the measure tool from the ramp to the far bank and you get the distance, the bearing and the shallowest point along it, marked rather than averaged into something comfortable.
Mark a spot when you find fish on Martin Lake or Lay Lake and the contours around it are right there to read. Saved spots, markers, routes and the logbook sync across your devices, so the run you laid out on the iPad at the kitchen table is on the phone at the ramp. On the drive up, CarPlay puts the lake and the ramp you are aiming for on the vehicle screen.
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.
Yes. Both are in the Alabama lake pack with contours and a depth reading on the water itself, built from state elevation surveys rather than from a nautical chart. Guntersville Lake is the largest named lake the pack carries, at 264.1 square kilometers or 65,260 acres, and Wheeler Lake is next at 211.1 square kilometers. Enter your draft and the water your boat cannot cross shades on either one.
The contours describe the shape of the ground under the water, and that shape stays where it is. The waterline is the part that moves, because a reservoir sits at whatever level it is being held at. Check the level on the day you launch and read the contours against it, the same way you would read the elevation survey the depth was built from. The first place the difference shows is the shoulder beside the old river channel, where the bottom comes up fast.
Because the packs are cut to a box rather than to a state line. Water sitting close to a border falls inside both boxes, so both downloads carry it, and the same thing happens along the Tennessee, Mississippi and Florida lines. It is also why the honest wording is the largest lake the pack carries rather than the largest lake in the state. For this pack that is Guntersville Lake at 264.1 square kilometers.
Helm Boating