Most of the big water in this pack used to be a river. Toledo Bend and Sam Rayburn are large enough that crossing one is a weather decision rather than a hop, and under both of them the old river channel is still the deep line. Lake Livingston and Lake Texoma sit open enough to build a chop by the middle of the afternoon. When the pool is down, the flats on either side of a creek channel are the part that changes first, and that is the part worth having shaded on a screen before you run it in the dark.
The pack covers 19,837 charted water bodies. Of those, 3,667 carry a name, and 307 of the named lakes are larger than a square kilometer, which is about the size at which you stop eyeballing a crossing and start planning one. The water bodies themselves come from the National Hydrography Dataset. The depth under them is built from state elevation surveys. That is the reason a reservoir shows up here with contours and a depth number on it instead of as a blue shape with a label.
Helm cuts 48 state lake packs, and this is one of the heaviest. The count of 19,837 charted water bodies is second among them. The 3,667 named water bodies rank fourth. The 307 named lakes over a square kilometer rank seventh, which is the figure that matters most if you tow to new water, because those are the lakes big enough to need a plan rather than a look around from the ramp.
The difference between the first two counts is 16,170 water bodies that arrive with no name in the dataset. Small stuff, mostly, and not what anybody drives two hours to fish. It is still worth having on the chart, because a map that draws the small water is a map that knows where the water ends.
| Lake | Charted surface area |
|---|---|
| Toledo Bend Reservoir | 668 km² (164,992 acres) |
| Sam Rayburn Reservoir | 451 km² (111,346 acres) |
| Lake Livingston | 335 km² (82,830 acres) |
| Falcon Reservoir | 325 km² (80,284 acres) |
| Lake Texoma | 240 km² (59,182 acres) |
| Sabine Lake | 229 km² (56,686 acres) |
| Lake Tawakoni | 151 km² (37,338 acres) |
| Cedar Creek Reservoir | 132 km² (32,593 acres) |
| Wright Patman Lake | 119 km² (29,381 acres) |
| Texas Industries Lake | 114 km² (28,195 acres) |
| Case Lake | 108 km² (26,687 acres) |
| Lake Lewisville | 106 km² (26,292 acres) |
The twelve largest named lakes the Texas pack carries, by charted surface area, measured from the chart polygon itself. The pack carries 19,837 charted water bodies in all, 3,667 of them named, and 307 named lakes larger than one square kilometer.
NOAA charts the coast, the intracoastal and the navigable rivers. It does not chart an impoundment out in the middle of a county, which is why a lake is an outline and nothing more in a lot of marine apps. Helm builds inland depth from state elevation surveys and takes the water body shapes from the National Hydrography Dataset. That pairing is what turns a lake into water you can draw a line across and check against your own draft, the same way you would check a channel on the coast.
A reservoir also sits at whatever level it is being held at. The dam decides that, and the surface can be well off where it stood last season, so a contour on a lake is tied to a surveyed water surface rather than to a fixed sea level. Reading one means knowing where the pool is today. The bottom does not move. The distance between your boat and it does. On a lake held low, the creek channel you have always run is still the channel, and the shoulders beside it are the part to watch.
Toledo Bend Reservoir is the largest named lake in this pack at 667.7 square kilometers, or 164,992 acres. Sam Rayburn Reservoir is next at 450.6 square kilometers, about two thirds the size. Lake Livingston and Falcon Reservoir land close together at 335.2 and 324.9 square kilometers, so they are the same class of water to plan a day across even though nothing else about them matches. Lake Texoma and Sabine Lake make the next pair, at 239.5 and 229.4.
Below that the drop is steep. Cedar Creek Reservoir, at 131.9 square kilometers, is just under a fifth of Toledo Bend. Lake Conroe, at 79.8 square kilometers, is a lake plenty of people would describe as big, and it is roughly an eighth the size of the largest one here. Every figure is measured off the chart polygon itself, which is why some of them will not match the number on a sign at the ramp.
The eight largest named lakes the pack carries:
The packs are cut to a box, not to the state line. A lake up against a border therefore sits in more than one pack, and both copies carry the same surveyed depth. The neighbors on this one are the Oklahoma, Arkansas, Louisiana and New Mexico packs.
If the water you run is anywhere near a line, take both sides down before you leave the house. The far bank is then charted too, and you are not looking at half a lake from the middle of it with no signal to fix the other half.
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. Both are in this pack with contours and a depth reading on the water, built from state elevation surveys rather than from a nautical chart. Toledo Bend Reservoir is the largest named lake the pack carries at 667.7 square kilometers, or 164,992 acres, and Sam Rayburn Reservoir is next at 450.6 square kilometers, or 111,346 acres.
19,837 charted water bodies, which is second among the 48 state packs. Of those, 3,667 carry a name and 307 of the named lakes are over a square kilometer. The shapes come from the National Hydrography Dataset, so the small unnamed water is drawn as well as Lake Livingston, Lake Texoma and the rest of the big ones.
Read them against the pool level for the day you are there. Inland depth here comes from state elevation surveys of the lake bottom, and the bottom does not change when the dam holds the surface lower. On a reservoir like Cedar Creek or Lake Palestine, the old creek channel stays the deep line as the pool drops and the flats on either side are what goes thin first. Enter your draft once and Helm shades the water your boat cannot cross, which is what puts those flats on the screen while you still have room to turn.
Helm Boating