Capt. John's Blue Water Lake:

Oronogo, Missouri

By Linda Lee Walden Photo by Lynn Laymon

In 1944 the Oronogo Circle (pronounced Or-or-no-go) mine was reportedly the largest open-pit lead and zinc mine in the world. Today the 230-foot-deep (70-m-deep) pit, now called Blue Water Lake, plays host to scuba divers from several Midwestern states.

The Days of Mining

The extreme western edge of the Ozarks, near the Oklahoma-Missouri-Kansas border, boasts not only fertile farmland, but also rich veins of metallic ore. Local folklore goes back to the early 19th century with stories of trappers extracting lead for their muskets from erosion-widened fissures.

As early as 1853 individual miners began working the Oronogo area, about 10 miles (16 km) north of Joplin, Missouri, and at one time more than 100 digs were in operation. While many of these amounted to little more than a single shaft in the limestone strata, so many of these claims existed that they formed a roughly circular pattern , thus the name Oronogo Circle.

Eventually, the small claims were bought out and consolidated by larger mining companies. To improve production, the mines were "glory holed," blasted to connect the individual shafts and drop the ceiling, creating a huge open-pit mine. A period of relative inactivity followed from about 1910 until the Great Depression, when Granby Mining and Smelting took over the Circle, expanding it and opening a series of new underground shafts.

The world's largest solid chunk of lead was removed from the Oronogo Circle mine and transported on two train cars for display at the 1933 Chicago World's Fair. At the peak of mining activities, between 1939 and 1947, an estimated 5,000 miners toiled in the area. Most were housed around the nearby town of Oronogo, swelling its population to near 20,000.

With the cost of extracting lead and zinc ore rising, and the need to ensure a steady supply of lead for munitions during World War II, the U.S. government began subsidizing mining operations. However, after the war the subsidies were discontinued and the local population dropped to less than 1,000 when the mine closed in 1950.

As with most former mine pits, when pumping stopped, ground water began to seep in. It took some time for several small natural springs to fill the 230-foot-deep (70-m-deep) hole, creating a 14-acre lake. Except for concrete bunkers that supported the mining equipment, the trappings of mining have either been removed by the departing corporation or demolished by weather. Gradually, elm and cottonwood trees covered the once flat terrain left hilly by 100 years of discarded overburden (crushed rock from which ore was extracted).

The Days of Diving

Today, as you approach the Blue Water Lake property, it isn't necessarily impressive , until you stand on the edge of the 30-foot (10-m) tree-topped cliffs that encircle the lake and look out at the inviting water visited regularly by migrating Canadian geese.

For three decades the lake served as a local party spot and swimming hole, until it was purchased by a Kansas City dive store owner. The property changed hands several times before Joplin scuba instructor John Mueller took over in 1987, naming the business Captain John's Sports and Scuba. Until recently, Mueller divided his time between the quarry and his dive boat operation in Belize, but has discontinued the latter to concentrate full time on improving the lake and the surrounding 32-acre property for divers.

One of Mueller's first tasks was to facilitate water entry by concreting the road formerly used by miners to access the pit. The concrete extends below the current water level to a natural limestone shelf, creating a stable, shallow-water ledge for donning fins and last-minute buddy checks. At the entry area, several gear tables have been added for convenient staging and a large underwater map of the lake is prominently displayed.

Once in the water, instructors typically have students snorkel a few hundred feet to Styrofoam floats that support a 25-foot-deep (8-m-deep) platform. The 10-foot-by-10-foot (3-m-by-3-m) platform is constructed of 2-by-10 boards in a steel frame topped by a 32-inch-high (81-cm-high) railing to prevent students from slipping off the sides during skill evaluation sessions. Buoys with down lines mark two similar platforms to the south of the entry area.

The old access road to the bottom of the mine slopes gradually downward in switchbacks along the near wall, the first turn occurring at about 40 feet (12 m). This shallow section is ideal for Open Water students and touring recreational divers. Many of the diver attractions have been placed on this level, including a six-passenger airplane, a small boat and several cars. Divers will also encounter less typical objects , a statue of an elephant, a 3-foot concrete gorilla and an entire personal computer setup.

As divers negotiate the switchback to continue down the road, they'll find a johnboat at 60 feet (18 m). Back toward the entry area, a surface platform attaches to a down line leading to another boat on the roadbed at 80 feet (24 m). On this level of the road, divers pass four archways that open into a large cavern. Carved by the mining operation, these openings were used to remove ore extracted from beneath the wall of the pit. Entering through any of the archways, cavern divers find themselves in a wide, 16-foot-high (5-m-high) chamber with a smaller room opening off the back.

After the second switchback, the roadway descends beyond the recreational diving limit (130 feet [40 m]) to the outer ring of the mine's floor. Technical divers, however, use this deeper part of the lake for extended range and trimix training and practice dives. Opening into the wall at 170 feet (52 m) are additional mine tunnels that create an extensive underwater cave system. Accessing this system requires extensive planning by trained cave divers.

Another underwater feature from mining days is a series of vertical shafts reaching from various depths down into small caverns in the wall to the north of the entry area. The largest of these is known as the Blue Room. Depending on whom you ask, the name describes either the clarity of the water coming from a spring in the room or the color of a wooden pole lying on the cavern floor.

Surprisingly, considering the variable climate of the region, the lake water never freezes. Even in winter when the air temperature plunges, the water only barely falls below 50 degrees Fahrenheit (10 degrees Celsius). The surface temperature rises to near 70 F (21 C) during the summer. Visibility varies according to season and weather; it can sink to 10 feet (3 m) or less during the spring and fall changeover, but has been reported as high as 60 feet (18 m). Mueller has stocked the lake with bighead carp to keep down algae growth.

Plans include sinking a helicopter and additional boats. A dock with multiple stairways for entry and exit directly into deep water is in the works for the north side of the current entry area.


Using the remaining concrete bunkers, Mueller has erected a two-story building housing Captain John's check-in counter, tank filling station, rental gear storage and a small retail area. Men's and women's restrooms, showers and changing facilities occupy the rear portion of the structure and a gear rinse hose has been installed out front. The facility fills standard air cylinders, plus nitrox and trimix through a partial-pressure system.

Next to the building is an enclosed pool, used by Mueller and his wife Regina, both scuba instructors, for occasional certification classes. Out front a patio with benches and tables provides a site for convenient picnicking. In the parking/camping area overlooking the quarry, groups of divers put up sun shelters, pitch tents and park RVs.

On a summer weekend, an average of 50 divers visit Captain John's, predominantly from Iowa, Missouri, Kansas and Oklahoma, but groups from as far away as Minnesota show up a few times a year. Divers are about equally divided between students and certified divers ranging from novice to technical.

Divers are asked to follow cold-water table rules at all times. Solo diving is not permitted and those intending to use double tanks must show proof of an appropriate technical certification.

Emergency oxygen is available on site, and if called upon, the Oronogo fire department rescue team can respond in five minutes. St. John's hospital in Joplin, about 13 miles (21 km) south, maintains a pressurized helicopter for airlifts to the recompression chamber in Kansas City.

Captain John's Sports and Scuba is located at 302 MM Hwy, Oronogo, Missouri. It can be reached from the north via U.S. Highway 71 and from other directions by Interstate 44. The facility is open from 4 to 8 p.m. Fridays, and 9 a.m. to 6 p.m. Saturdays and Sundays. This year Mueller plans to close from Christmas through March 2004. Entrance fee for divers is $10 per day. For detailed directions and prices for cylinder fills, please call (417) 673-2724, check or e-mail