Technical Diving in Missouri

Cold weather and snow makes us technical divers' dream of doing a deep wreck dive on Trimix off Miami or going on a magnificent cave dive in the warm, clear waters of Akumal. But like myself, most of us can only travel to these destinations once or twice a year during our well-deserved vacations. But there are alternatives which I would like to present to you in this article.

I am very fortunate to live in Missouri, more precisely in the Ozarks. Due to the geological history of Missouri, this region is abundant with caves, above and below water, of which the submerged caves are of interest to us. Most of the caves which are available for cave diving are located within a three-hour drive from St. Louis, making them ideal weekend dive destinations for many technical divers living in the Midwestern states like Kansas, Illinois, Indiana, etc.

Probably the most popular cave dive is in Roubidoux Spring, Waynesville (Mo) due to its easy access. After signing in at the Waynesville police station you will be issued the gate key which allows you to park directly next to the spring. There is room for about eight vehicles with additional parking available on top of the little hill. After entering the cave one finds himself/herself in a large cavern zone, ideal for cavern divers. The main line begins about 75 feet back and leads into the upper tunnel. After about 350 feet at a depth of 45 feet you reach the drop-off which stairsteps from 45 feet down to about 145 feet and funnels into the gravel pit. At the gravel pit the lower tunnel begins and goes for about 1200 feet at an average depth of 150 feet until it ends in which is called the Big Room where the bottom drops to a depth of 165 feet. The permanent line continues on to what is called the Second Big Room, but this is beyond the scope of my experience. Before attempting the first Big Room one has to understand that the lower tunnel has only an average height of 4.5 feet and due to its depth penetrations into the lower tunnel carry a high decompression obligation. At a temprature of around 50 degrees Fahrenheit this needs to be taken into consideration when planning a dive in Roubidoux Spring. Deep penetrations into the lower tunnel are best accomplished using scooters, unless you like long decompression times. Visibility ranges from 20 to 70 feet, depending on the amount of rain the area has experienced. The flow is usually dependent upon the same factor. During the summer months excellent visibility with little flow can be expected. After completing the day's diving do not forget to sign out at the police station.

Another popular cave, and my personal favorite, is in what is called Cannonball Spring which is located in the bottom of Lake Wapapello, an Army Corps of Engineers lake near Popular Bluff. After a treacherous climb down an extremely steep hill, or if you have a scooter get in around the bend, one dives through the lake to the entrance of the spring at a depth of about 25 feet. After slipping through a restriction, the main tunnel begins and continues for about 900 feet before ending at the drop-off with an average depth of about 45 feet. There are several small side tunnels, also leading to the drop-off, which can be explored, but they are very tight and extremely silty.

The main tunnel has a height anywhere from 10 feet to 20 feet which makes it easy to swim through. On the way to the drop-off, you will encounter rock formations that look like archway bridges and many other interesting geological formations. Once at the drop-off you will be overwhelmed by its enormous size. Every time I see it I am fascinated by its huge dimensions. After a straight drop down to a depth of about 210 feet, the tunnel slopes further down at a 45-degree angle reaching a depth of 295 feet, making this an ideal Trimix dive. At this point, there is a restriction and what lies beyond it remains yet to be explored. By using EAN50 back to the drop-off, then switching to your bottom mix (Trimix), and on the way up doing multiple gas switches (utilizing the max allowable PO2) the decompression times can be kept within reason. This is due to the fact that the swim back from the drop-off is an excellent opportunity to offgas. As becomes evident through the examples in the two accompanying tables, deep dives in Cannonball Spring require tremendous dive planning and deeper excursions suggest, maybe even require, the use of support divers.

Remember that these are only two examples of possible dive plans and that there are many other alternatives with respect to gases used, depths of gas switches, etc. But a dive in Cannonball Spring is well worth the effort as its visibility can reach 70 feet and more during periods of little or no rain. Flow is usually low unless it has rained a lot during the weeks prior to the day of the dive. And make sure you do not forget to bring a rope to help you get down that damn hill.

Within an hour's drive from St. Louis there is an old lead mine system called the Offsets or Mine LaMotte near Fredericktown which offers cave diving with excellent visibility (70 feet or more) at shallow depths. To my knowledge the deepest you can get in there is about 70 feet, with most diving taking place in the 30 to 40 foot range. Mine LaMotte offers you an excellent opportunity to dive into the past days in mining. Old mine carts and plenty of other relics are still present in these flooded tunnels. Some tunnels contain air pockets where you can get out of the water and explore on foot. But be sure to maintain a continuous guideline to the entrance since this mine system is like a maze with different levels. Permanent lines are installed, but there is such an immense number of tunnels with lines in them that someone diving it for the first time could easily get confused. So follow all the rules of safe cave diving. The owner is really friendly to cave divers and only charges $10 for the day. There is also an open pit for recreational diving and swimming. Mine LaMotte can be dove all year, but in the winter months it is best to call the owner and let him know you are coming.

Another location that allows us to engage in technical diving is Blue Water Park in Oronogo, Mo., near Joplin. This used to be an open-pit mine with some extensive tunnels running for miles. With a surface area of 14 acres and a maximum depth between 210 and 220 feet, this is a relatively large body of water. There are diving opportunities for every skill level. The old road, with a depth from 10 to 60 feet, offers plenty to see (airplane) for the novice diver, whereas the ledges at 130 feet, 150 feet and 170 feet with their tunnels offer diving for the technical diver.

The owner now requires the technical divers to join a form of club with an annual fee which enables the technical divers to be covered by insurance. Time will tell how this new system will work. Dive plans must be filed with the shop and excursions into the deep tunnels require special permission. Some of the tunnels in the shallow portion of the pit allow for training cavern divers. Nitrox and Trimix are available at the dive shop on site.

Black Jack Mine in Galena, Kansas, near Joplin, is another excellent cave dive. It is made unique by the fact that it was hand mined, which makes it look more like a cave than a mine. Although the south tunnel is currently being filled in, good relations with the land owner have preserved the more scenic north tunnel for us cave divers. Black Jack Mine has many side tunnels that can be explored and old mining tools still lay scattered throughout the mine. Especially noteworthy is the old winch which was used to pull the mining carts. With a maximum depth of 80 feet and visibility up to 70 feet and more, one can spend long enjoyable dives in Black Jack Mine. Entering the mine has been made easy by stairs that lead down to the entrance and continue about 12 feet below the surface. The owner is very friendly and, although he does not charge to dive there, it is customary to give him $5 per diver.

Table Rock Lake also offers opportunity for deep dives well below 200 feet near the dam, but it is extremely wise to find out from the engineers when the gates in the dam are opened for power generation, since this creates strong currents close to the dam.

There are many more excellent sites for technical diving in Missouri, but local bureaucracy and individual opinions prevent us from diving these sites legally. But efforts to change this are under way.

I hope this short description of a few dive sites has made the mouth of some of you technical divers water and maybe you will come to Missouri for a weekend dive trip. There are several IANTD facilities in Missouri, so dive support and service is available. All offer Nitrox fills and two offer Trimix fills, along with the opportunity for continued training in technical diving.