The largest salt-water lake in the western hemisphere, and the largest inland body of water in the U.S. next to the Great Lakes, sits at the doorstep of Tooele County. The Great Salt Lake is so large, Jim Bridger, that famous mountain man who helped shape the American West, mistook it for an arm of the Pacific Ocean after taking a sip of its brine.
Many travelers and Tooele County residents routinely zip past the Great Salt Lake as they rush east or west on Interstate 80. A quick glance out the window while driving by allows for only a cursory look. To better know the lake’s unique character and size, to take it all in, one must stand beside it.
But there is only one place in Tooele County where the curious traveler or resident can step outside of their vehicle and walk the shores of the Great Salt Lake and dip a toe into its salty water.
The Captain Stansbury Visitor’s Overlook on Stansbury Island opened in 2009. Located 25 miles northwest of Grantsville, the overlook is a cooperative effort between US Magnesium, Tooele County, the Bureau of Land Management, the state Division of State Parks and Recreation, and the state Division of Forestry, Fire and State Lands.
Named after Captain Howard Stansbury, whose crew camped nearby while surveying the shoreline in 1850 for the U.S. government, the overlook has a parking lot, restroom and informational kiosks. Nearby is a trailhead for an interpretive trail that tells the 33,000-year history of the Great Salt Lake and its ancient predecessor, Lake Bonneville.
Step out of your car at the overlook and you are at the bottom of Lake Bonneville, which some 20,000 years ago, the surface was 1,000-feet above your head. The surrounding hills reveal countless high water marks left behind by the ancient lake as it rose and fell numerous times.
A set of interpretive kiosks, prepared by Dr. Genevieve Atwood of Earth Science Education, tells the story of Lake Bonneville and the Great Salt Lake. The kiosks help you recognize the five major levels of both lakes. They also provide information about the geologic, natural, and human history of the lakes and the area.
At its peak, Lake Bonneville once covered 20,000 square-miles from southern Idaho to Southern Utah. For comparison, Lake Michigan covers about 22,000 square miles. The Great Salt Lake now averages 1,700 square-miles and its deepest point is 33 feet.
The 1,000-foot long interpretive trail that starts just north of the parking lot is a scale model of both lakes’ history. A sign placed every 100 feet long the trail marks the passage of 33,000 years.
The trail’s gain and loss in elevation also mimics to scale the rise and fall of the lakes’ level. Ten feet of elevation change equals a 50-foot change in water level.
Debris at the bottom of the trail was washed ashore from high water in the 1980s. Pieces of lumber from a trestle that once traversed the lake, reminiscent of ocean beach driftwood, is found scattered in the grass and wet marshes.
You can reach down and pick up a handful of unusual round sand that is found along the shoreline of the Great Salt Lake.
Each piece of sand is made of small, perfectly round pieces called “oolites.” They are concentric layers of calcium carbonate formed around a central core made of a tiny brine shrimp fecal pellet or a mineral fragment. These oolites were created in shallow, wave-agitated water, where they gradually accumulate more and more layers.
Large boulders with perfectly round holes are strewn along the trail. The holes are panholes created by deposits of water that sit for great lengths of time and dissolve the minerals in the rock.
The overlook area is far enough away from I-80 (about 12 miles) that visitors can’t hear traffic. The quiet allows you to imagine what the lake looked like before Bridger set his eyes on it.
The overlook also gives opportunity to observe modern man’s way of harvesting the Great Salt Lake’s potential. To the west across Stansbury Bay from the overlook is the US Magnesium plant that extracts magnesium from dissolved minerals deposited annually in the lake.
Also north from the overlook you can observe a brine shrimp operation. The workers harvest the tiny shrimp, one of the few organisms that thrive in the lake’s brackish water, and sell them primarily as feed for the aquaculture industry.
The Captain Stansbury Overlook and the Stansbury Island Interpretive Trail are an excellent trip for a family, youth group or school class. The kiosks and trail signs allow you to understand the beauty and history etched into the mountains by the Great Salt Lake.