About Bear River
Springing from sources in the snow-capped Uinta Mountains, the Bear River winds through valley grasslands, between sagebrush-covered hills, working its way around around the Wasatch Mountains to reach the Great Salt Lake. Verdant farms and ranches surround the river, with occasional rural communities.
With a length of about 500 miles, the Bear River has the distinction of being the longest river in the western hemisphere that does not empty into the ocean. The forested northern slopes of the Uinta Mountains lie just south of the Utah-Wyoming border, and close to the point where the border changes direction from east-west to north-south. Utah Highway 150 crosses the Bear River near where the Hayden and Stillwater Forks converge into the Bear River. The highway follows the river northward into Wyoming where its canyon widens into a valley at 7,500 feet in elevation, and the impressive peaks slip into the background.
Low hills, covered in sagebrush, close in on the valley, as the river continues north. It passes through Evanston, the largest city on its route. North of Evanston, the river reaches the Session Mountains. Here a low hill crowds the river up against the mountain, and forces it into the Woodruff Narrows, an unspectacular but surprising geologic feature. The river for no explicable reason, cut a channel a thousand feet deep into the mountains, then turns around comes out near where it entered. The gorge is a few miles long, and begins about a mile from where it starts. A gentle hill about 60 feet high separates the two points.
Emerging from the Woodruff Narrows, the river heads straight west for few miles, into another wide valley, crossing into Utah. Once in the valley it turns northward again, following the base of the Crawford Mountains. At this point the elevation has come down to about 6,300 feet. For many miles it roughly follows the Utah-Wyoming border northward, passing the ranching communities of Woodruff and Randolph. Veering slightly to the east it crosses into Wyoming again, and passes through Cokeville. Just north of Cokeville, the valley narrows down, and it passes into the Thomas Fork Valley.
In the Thomas Fork Valley, the Bear River makes an abrupt turn to the west and passes through a gap in the mountains and into Bear Lake Valley. In some prehistoric time, no doubt, Bear Lake filled the valley, and the river flowed right into the lake. However, when the valley was settled, the lake occupied the lower southern end of the valley, while the river turned to the north, passing through another gap in the mountains. In order to store the water of the river, a canal was dug and the river diverted into the lake. Another canal was dug to return the water from the lake to the river.
To the north, the Bear River follows a narrow valley, turning gradually to the west, passing Soda Springs, and entering Gem Valley. In prehistoric times, the river used to flow straight west across the valley, and followed the course of the Portneuf River into the Snake River Basin. From there it presumably would have flowed to the Pacific Ocean. This changed when a lava flow blocked the path of the river where it entered Gem Valley. Being forced out of its course, it turned to the south and cut the Oneida Narrows through hills leading into Cache Valley. At that time Cache Valley was part of ancient Lake Bonneville, covering most of Utah. The additional water from the Bear River contributed to the lake overflowing its rim, sending a tremendous flood into the Snake River Basin.
In Cache Valley, the river turns west again, cutting through a gap in the mountains, and enters another valley, named the Bear River Valley. From here it flows south until it reaches Great Salt Lake.
The Bear River dumps an average of 1.2 million acre feet per year into Great Salt Lake. A dike was built around the northeast corner of the lake to form Willard Bay, a freshwater portion of the lake. The Bear River is the largest river that empties into the lake.
Along the course of the river, it passes through many valleys that are called the Bear River Valley. In spite of this, they are really separate valleys, formed in between uplifted mountains, connected only by the erosion of the river.