Prairie Diving: North Dakota's Lake Sakakawea

By Linda Lee Walden Photos by Lynn Laymon

In 1804 Lewis and Clark set out to find a water route to the Pacific Ocean. They followed the Missouri River through the Northwest Territory into what is now North Dakota. Here, the expedition was joined by a Canadian fur trapper and his wife, Sakakawea,  whose knowledge of the land and native peoples was invaluable to the success of the mission.
Although Lewis and Clark did not discover a navigable waterway across the North American continent, the journey did open the upper Missouri River basin to exploration and settlement. Much later, in 1954, the U.S. Army Corps of Engineers completed construction of Garrison Dam, the fifth-largest earthen dam in the world, 75 miles (120 km) upstream from Bismarck, North Dakota. 
The enormous reservoir created by the dam was named Lake Sakakawea, in honor of the famous Native American guide. Today the 178-mile-long (285- km), 6-mile-wide (10-km) lake provides flood control, hydroelectric power, fish and wildlife habitat, irrigation and recreation, including scuba diving.

The Diving
Lake Sakakawea was formed from the broad Missouri River and the gently rolling North Dakota prairie. At its normal level the water measures about 200 feet (61 m) deep at the old riverbed and 170 feet (52 m) on much of its relatively flat expanse. A decade-long drought, however, has brought the current water level down more than 30 feet (9 m).

Because the Lake Sakakawea State Park with its marina and boat-launching ramp is just west of Garrison Dam, much of the scuba diving takes place at nearby sites, including the face of the half-mile-thick earthen dam.
Covered with large boulders, the wall slopes at about a 45-degree angle from the top of the dam to its lakeside base at 12-14 feet deep (3-4 m, at current low-water level). From the base of the wall the rock and mud bottom slopes gradually, flattening out around 100 feet (30 m).
Instructors position students at the relatively sheltered area adjacent to the base of the rocks for skill evaluations. Visibility on the dam wall, as in the rest of the lake, varies greatly with the weather. High winds, especially from the northwest, stir up the bottom and can reduce visibility to near zero, but in mid-summer it rises to 30 feet (9 m). 

Water temperatures range from near freezing in winter to the high 60s (Fahrenheit, high teens Celsius) in August, however, the thermocline found at deeper recreational depths never dissipates. 
The craggy dam face serves as a congregating area for schools of bass, carp and walleye. Although recreational diving season doesn't typically start until early May when the ice has melted, preseason divers may catch a glimpse of a paddlefish cruising near the dam.
Paddlefish also congregate below the dam in the tail race. Bottom feeders, they scavenge for bits of fish that were sucked through the intake of the hydroelectric plant into the turbines and discharged into the outflowing stream.

As questionable as it might at first seem, the tail race is a popular site for drift diving. This shallow channel, 17-foot average depth, was created to return the outflow from the plant to the natural streambed of the Missouri River. Boats drop divers a safe distance downstream from the outflow tubes and follow their float and flag as they drift. 

Algae and grasses grow along the rip-rap banks of the tail race. Lingcod, salmon and "suckers" can be spotted, as well as artifacts from the building of the dam, such as steel cables and large concrete forms.
Despite the shallow depth, the temperature in the tail race remains chilly year-round since the intake pulls water from deep in the lake. Visibility can be as good as 30 feet (9 m).
Current in the tail race varies between a benign 1.5 knots to 4 knots, suitable only for experienced drift divers. Water discharge schedules are posted in local newspapers, but it's best to book dives through local dive stores, which are familiar with dive conditions above and below the dam.
Although less accessible, diving is also possible elsewhere in Lake Sakakawea, however, the upstream end is more susceptible to changes in weather. For multiday charters, dive centers trailer their boats to one of the many public boat launch ramps along the lakeshore. 

The main attraction for divers in the "Deepwater" arm of the lake, about midway to the upper end, is spearfishing. Lake Sakakawea is rated by topside anglers as one of the best fishing lakes in the United States. Walleye, perch, lingcod and salmon are common. Dive centers from as far away as Minnesota plan trips to spear the highly rated Lake Sakakawea walleye.

Walleye follow the seasonal flow of the river. In spring they are more active in the upstream regions as visibility improves with runoff from melting snow. Dive charter boats anchor near shore in 10-40 feet (3-12 m) of water. The underwater topography is generally a continuation of that above water. The bottom steps down in a succession of bluffs and hills to the flats adjoining the former riverbed. 

In addition to spearfishing, divers interested in geology can find unusual rock structures and fossils in the banks of the old river; the occasional piece of petrified wood is indicative of the above-water origins of the lakebed. Bass and northern pike hide in the tall grasses that grow in the numerous shallow bays.
At one time shore diving was an option, but the region has been in a drought for almost a decade and the level of the lake has dropped significantly, making shore entries difficult and impractical.

One exception is ice diving. From December through April, large portions of the Lake Sakakawea shoreline are ice-covered. In cold years the ice can be as thick as 36-48 inches (91-122 cm), enough to support a car. Dive centers drive a vehicle from one of the boat launches a couple of hundred yards out onto the lake to set up a base camp. Curiosity is one of the big factors that prompt hardy divers to participate in this rigorous type of diving, but the frozen lake is also used for winter training of water rescue and recovery personnel.

The most developed portion of the 1,300 miles (2,080 km) of Lake Sakakawea shoreline is near Garrison Dam. 
Lake Sakakawea State Park includes a full-service marina with a boat launching ramp. At least one dive charter service maintains a slip in the marina, and several dive centers trailer their boats and put in there. Boat rentals are also available.
At the marina there is a camp store with a snack bar, restrooms and sundries, but no scuba supplies. Gear, including tanks and air fills, must be obtained at an off-site dive center. The marina is open from whenever the last ice melts through October.
The state park includes a 300-site campground with electric and water hookups, dump stations and restroom/shower buildings.
No matter where on the lake one is diving, ambulance services are no more than 20 miles (32 km) from a boat launching point, and Riverdale emergency services are just east of Garrison Dam. For serious injuries, a helicopter ambulance is available from Minot, 30 minutes away by air. Marine radios are at the state park marina and on county patrol boats. Cell phone service does work for 911 calls.

The best way to dive Lake Sakakawea is with a dive center that frequents the venue. In North Dakota, there are dive operations in Bismarck, Mandan and Minot. Dive centers in South Dakota, Minnesota and Montana also run multiday dive trips to the lake.

Lake Sakakawea can be reached from Interstate 94 via U.S. Highway 83 (North Dakota exit 159) and State Route 200. A daily entrance fee of $5 applies and camping is $8 to $15 per night in season (May 20 through September 30).

Pick City, a small town just outside the state park, offers motel accommodations and food services. 
The state park is closed after dark, but night diving is permitted for those staying in the park's campground.
For more information on Lake Sakakawea State Park, visit, call (701) 487-3315 or e-mail Camping reservations are handled through (800) 807-4723.

Sakakawea or Sacagawea?
Various legends tell of the origins of Lewis and Clark's Native American guide. 
One places her as a Shoshone, abducted as a child from Montana and raised by Hidastas in North Dakota. In Shoshone, Sacajawea means "boat launcher."

In expedition journals her name was written many times as Sacagawea, pronounced phonetically with a hard "g."

Believing that she was actually born Hidasta, the Three Affiliated Tribes (Hidasta, Mandan and Arikara) of the region endorse the Sakakawea spelling, which means "bird woman" in Hidasta.