ARKANSAS ' LAKE OUACHITA :

A Diamond of a Dive

Story and photos by David Prichard and Lily Mak

Some of the world's most exotic, faraway dive destinations feature hundreds of islands where divers can see jellyfish, sponges and a wide variety of marine life in clear visibility. But there's one place where can you see those creatures, along with an abundance of quartz crystals — and it's in a freshwater lake in Arkansas .

In one of the most geologically complex areas of the world, Arkansas' Lake Ouachita (Wash'i taw) is in the middle of the Ouachita National Forest with about 1,000 miles (1,600 km) of shoreline with no residential development other than four marina/resort projects. This lack of human development helped rank the lake as one of the top three cleanest lakes in the nation and allowed the development of freshwater jellyfish and sponges.

Besides the approximately 200 islands in the 40,100-acre (16,040-hectare) man-made lake, divers can also explore numerous submerged mountaintops and abandoned settlements in one of the few North American mountain ranges that run east and west. West of the natural spas of Hot Springs and just north of the only diamond mine in North America, the Lake Ouachita region has long been a destination for "rock hounds” collecting rare natural minerals. One dive site in the lake includes one of the largest veins of quartz crystals in the world.

A Sea of Change

More than 450 million years ago, an ocean covered this area of Arkansas . Deep deposits of sediment later compressed into sandstone. Around 250 million years ago, the crust of the Earth was uplifted in this region — in a way that still baffles geologists — to create the East-West Ouachita Mountain range. Silica-rich groundwater seeped out of bedrock fractures and crystallized into quartz veins.

Over thousands of years, the Ouachita River formed a wide valley through the mountains. Spanish explorer Hernando de Soto is credited as the first European to explore the valley as he encountered the Washita, Caddo, Osage and other native tribes that inhabited the prosperous hunting area. In 1803, President Andrew Jackson sent the survey team of George Hunter and William Dunbar to explore the region after it was acquired in the Louisiana Purchase . They were the first explorers to document the hot springs of the valley.

In the early 1930s, the government began buying up land at $30 per acre to create the lake. Many towns were relocated and by 1953 the 1,100-foot- (333-m-) long Blakely Mountain Dam was in operation. The Ouachita River , numerous springs and streams quickly created a 40-mile- (64-km-) long lake that is managed by the U.S. Army Corps of Engineers and is part of the Arkansas state parks program. The park features more than 1,000 campsites in 21 recreation areas.

Diving the Lake

In addition to attracting Arkansas divers, the lake pulls in scuba enthusiasts and training classes from Oklahoma , Texas , Louisiana and Mississippi on a regular basis. Despite the many miles of shoreline, access for divers is somewhat limited. Since it is against park regulations to dive from the marina, campgrounds or swimming areas, many use a variety of boats to visit the dive sites around the lake's uninhabited islands.

Many of the local dive centers have invested in pontoon dive boats to take their classes out to a variety of underwater settings. Some dive boats have training platforms attached to the underside of the boat. After the boat reaches a clear, shallow area near an island, the platform is lowered to the desired depth, away from bottom silt. After the student divers perform their skill demonstrations, the group then leaves the platform to explore different sites on each dive.

The main shore entry for divers is at the far end of the Blakely Mountain Dam. A long series of steps lead from a parking area down to the water and then continue deep into the lake's depth. From the submerged stairway there are cables laid out in a path to a series of sunken boats and vehicles at a variety of depths. This area has some of the clearest visibility in the lake with no current from the hydroelectric dam. The rock face around the dam can reach about 190 feet (58 m) deep.

Water visibility varies around the lake, but increases everywhere past the first thermocline, up to 40 feet (12 m). Despite warm surface temperatures during the summer months, the water temperature can plunge as much as 20 degrees Fahrenheit (11 degrees Celsius) past the thermocline, so divers need proper thermal protection when diving deep.

With boat access, there are several popular dive sites around the lake. Crawdad Island is named after its shape rather than its inhabitants. The eastern side of the island slopes gradually underwater, which is good for novice diver exploration. The western side features a rock wall with large boulders that drops deep into the former riverbed. A sunken boat can be found off the north end.

Zebra Rock is named for its abundance of vertical veins of white quartz that give the appearance of zebra stripes in the rock face. Divers can look through the loose rockslide below the veins to find quartz crystals.

When the mountains were being formed, the uplift pressure on a section of hard sandstone caused the rock to fracture into a checkerboard pattern at what is now called "Checkerboard Point.” The large cracks between Checkerboard's square boulders provide protection for many small fish that, in turn, attract bigger fish for divers to observe.

Unusual Sights Below the Surface

From late May through October, divers can expect to see swarms of small freshwater jellyfish (craspedacusta sowerbyii) swim by them. These bell-shaped hydrozoa are translucent with a white or green tint and are usually less than 1 inch (25 mm) in diameter. They feature four long tentacles for swimming and many shorter ones in-between for feeding on zooplankton.

These thimble-sized jellyfish do possess nematocysts to harpoon prey, but they aren't big enough to penetrate human skin. Originally from China , a form of the polyp version is often attached to ornamental aquatic plants, fish and the feet of birds. When these plants and creatures are transported to other countries, the jellyfish hitch a ride. While they can be found in many warm-water settings across the United States , Lake Ouachita 's clean waters have allowed the jellyfish to reproduce in numbers large enough to be noticed by the average observer.

The best time to see the jellyfish is in September after several hot summer months. They can be seen at depth and floating on the surface from the middle of the lake to the shoreline.

Another underwater rarity at the lake that divers get to see is the freshwater sponge (spongilla demospongiae). The sponges are most noticeable in the fall season and can get to "saucer” size in the lake. They are usually light tan to green, thin and look like a sponge attached to rocks and tree trunks.

The multicellular animal acts as a sieve to filter microscopic life from the water. Like the jellyfish, the sponge dies in the late fall, but not before forming a seed-like body called a gemmule that is immune to freezing and drying. This gemmule can be transported by wind, water and birds' feet to other bodies of water.

A Fishy Mix

While Lake Ouachita features traditional freshwater lake fish like largemouth and smallmouth bass, rainbow trout, crappie, sunfish and two varieties of catfish that can reach 100 pounds in size, another pair of fish often make headlines. Lake Ouachita is often called the "striped bass capital of the world.” Bass have been annually stocked in the lake for more than 30 years. The large sport fish can reach 40 pounds (18 kg) in size.

A problem the lake faces from another invasive marine species from China has allowed a predator fish to swell in numbers. Out of 40,100 acres (16,040 hectares) of water, the lake has nearly 12,000 acres (4,800 hectares) affected by the fast-growing hydrilla plant, with tall stocks often reaching to the surface from deep water. This environment has enabled the chain pickerel (also known as pike or jackfish) to flourish.

Their needle-like body, resembling a freshwater version of a barracuda, allows them to easily maneuver through the thick vegetation to quickly ambush prey or to dart for cover when threatened.

To combat the problem of hydrilla, the Corps of Engineers is turning to another imported creature. The Pakistani hydrilla leaf-mining fly's larvae (hydrellia pakistanae) burrow into the leaves of the plant. Each larva can destroy nine to 12 leaves during its feeding cycle. The corps is treating 13 areas with the tiny fly that resembles a gnat in size and hops along the water surface rather than flying. The Arkansas Game and Fish Commission is also stocking the lake with thousands of grass carp, a fish that prefers to eat hydrilla.

With the abundance of game fish, Lake Ouachita allows divers to use spear guns to catch fish from June 15 to March 15 each year. Divers are allowed half the normal limit of anglers and must have a fishing license.

Geo-Float Trail

Because of its many unique geological features, the Corps of Engineers has published a brochure guiding boaters along a 16-mile (26-km) "Geo-Float Trail” that explains many of the natural formations of the lake. Many of the stops listed are also some of the lake's most popular dive sites, such as Checkerboard Point, Zebra Rock and Whirlpool.

With an abundance and wide variety of marine life, both large and small, Lake Ouachita attracts many divers to its clean water in its mountainous, forest setting. Along with the sparkle of quartz crystals, the lake shines like a "diamond” among the nation's freshwater dive sites.

Getting There

To Lake Ouachita State Park, from Hot Springs in central Arkansas, travel three miles (5 km) west on U.S. 270 and then 12 miles (19 km) north on Arkansas Highway 227 to the park.

Contact Information:

Lake Ouachita State Park Visitor Center , (501) 767-9366

Corps of Engineers (COE)
Field Office, (501) 767-2101

COE National Recreation
Reservation System, (877) 444-6777

www.lakeouachita.com

www.hotspringschamber.com

www.mtidachamber.com

www.ReserveUSA.com

www.ArkansasStateParks.com

Many Arkansas dive centers visit and have information about Lake Ouachita