The History of the Off-Sets

Mine Lamotte is a small town approximately one hour south of St. Louis, Missouri. There is a lot of history surrounding this little town in Missouri. Offsets mine (also known as Mine Lamotte) dates back to the 1600’s when the Indians practiced mining on a small scale. Among the lead mines discovered, Mine Lamotte in Madison County, is one of the earliest and most important in the state of Missouri.

The first prominent white man to set foot on the soil of what is now called Mine LaMotte, in the early 1700’s, was the Sieur Antoine de la Motte Cadillac, governor-general of the colony of Louisiana under the Royal Company of the Indies. During the civil war, there was a southern raid on the mines at the time of the Battle of Fredericktown.

The southerners captured 18,000 pounds of lead and took it back to Arkansas. The Northern army then destroyed several furnaces at Mine LaMotte to keep the South from getting any more lead. For most people, Mine LaMotte today is simply a place for the locals to come and swim or dive. But to those who remember or who have chosen to learn of it’s past, this mining town still holds one’s imagination of days gone by. And for certified cave divers, we can get a glimpse of those days gone by.

Gary Henson, the current owner of Offsets mine, has opened it up as a recreational area. The area now offers swimming and diving for a daily fee. To dive inside the mine, you must be cave certified and present your cave card at the entrance.

Offsets mine is definitely an advanced cave dive. You must remember that this is not a cave, but a man-made mine, and thus, subject to some possible unstable areas. Good skills must be employed at all times. Visibility is generally poor in the shallower sections with virtually no cavern zones. As you get further back and deeper (below 40 ft.), the water gets colder, generally 40-45 degrees all year long. But in compensation for the colder temperatures, you usually get good visibility.

Most of the original exploration was done by Mike Heusack, from St. Louis. Mike has laid thousands of feet of line and is probably the one of a few with a complete idea of the extent and complexity of the labyrinth of tunnels. But up until now a survey or map had never been produced. Currently a survey is being conducted with hopes of producing a map in the near future.

Despite the seemingly ominous environment, Offsets mine offers a great look back into the past. You can see old mining techniques and equipment left abandoned when the mine flooded. Ore carts, picks, shovels lie along the abandoned road beds. You can still find the old pump sitting stodgily in a ghostly room in one of the deeper areas of the mine. As you swim through the numerous roads and tunnels of the mine, lined with the old electrical fixtures, you can pick out the older methods of mining where they used timber/shoring techniques (please use extreme caution in these areas) and then in others see the newer rock/pillar techniques. Occasionally you will see footprints in the old roadbed left by the workers of the mine.