The Dam at Flaming Gorge Reservoir has a visitor center and a lot of plaques and monuments to read, here’s some of it:

Early Inhabitants

People have lived in this area for about 10,000 years. While the first inhabitants dwelled mostly in open areas, our best preserved evidence of their culture has come from caves, and shows a mobile hunting-gathering society.

At a much later date, some 1,500 years ago, the Fremont Culture appeared. These horticultural people made some use of caves and lean-tos, but also existed in sedentary villages with pithouses. Cultural evidence of the Fremont People disappears some 650 years ago, leaving their destiny as one of today’s archeological mysteries.

Built for Fish

Most of the water in the Green River for 60 miles (100 kilometers) below the dam is released from the reservoir through the powerplant. Because the turbine intakes are about 200 feet (60 meters) below the surface of the reservoir, the water releases were rarely about 40° F. (4° C) – too cold for the downstream fishery.

To remedy this, a “Selective Withdrawal Structure” was installed. It allows water for power generation to be taken closer to the surface where the temperatures are warmer. When the warmer water is released into the river, it helps provide am improved habitat.

Geology Along the Byway:
History Recorded in Stone

All around you are ancient signs of advancing and retreating seas, swamps, barren deserts, dry uplands, wandering streams, lakes and rising mountains. Look for them in the layers limestone, sandstone, mudstone and shake as you explore the Byway. Each rock layer represents an extinct ecosystem which contains the fossilized remains of plants and animals.

Roadside signs identify the names of rock formations along the Byway. Each formation was deposited in horizontal layers of sea mud, sand, silt and clay. Shifting of the earth’s crust tilted these rock beds, and erosion exposed the layers like an open book which you can still read today to learn more about the geological and biological history of this area over the last billion years.

Flaming Gorge Area Fish:
Wildlife in a Watery World

The native fish of the Green River are highly adapted survivors. Before the dam was built, run-off from melting ice and snow funneled into the river creating whitewater rapids and lowland flooding. The waters in the spring were cold, powerfully swift and muddy, followed by warm water moving slowly through the braided sandbars in the summer. In the fall, the waters cooled again and the froze in the winter. Those species that adapted well enough to survive these conditions incorporated the seasonal changes into their life cycles.

These fish were survivors. They handled Green River’s changing faces for hundreds of thousands of years. But then people arrived and built concrete plugs in the river. This blocked migration routes, moderated spring floods and caused the river to run cold all year. New habitats for cold-water fish in reservoirs and streams were created and newly introduced fisheries are now flourishing. Only time will tell if the native fish, the survivors, can adapt once more.

  • Bonytail Chub
  • Brown Trout
  • Colorado Pikeminnow
  • Humpback Chub
  • Kokanee Salmon
  • Lake Trout
  • Rainbow Trout
  • Razorback Sucker
  • Smallmouth Bass
  • Utah Chub

Ospreys: Skydiving for Fish

From a distance, those white-headed birds that hover over the reservoir in summer might look like small bald eagles. But actually, they’re ospreys, also known as fish-hawks. It is our good fortune that Flaming Gorge Reservoir is home to Utah’s largest breeding population of ospreys. These large raptors feed primarily on fish. Using their keen aim and eyesight, they dive into the water from heights of 100 feet or more, extending their talons at the last second to pluck their supper from the water.

Around the first of April, males migrate to the area and select what they consider to be an attractive nest site. A couple weeks later, the females arrive and check out the males’ selection. If a female osprey likes what she sees, she moves in and helps construct the nest. Ospreys usually return to the same nest and mate with the same partner, so nest site selection and construction are important parts of the courtship displays.

Once the pair moves into their new home, the female osprey lays one to three eggs which hatch five weeks later. The young are born helpless and are totally dependent on their parents for food and shelter. The makes supplies all of the food for the female and their young. Nine weeks after hatching, the chicks are ready to learn to fly. A month later, they have to fish for themselves. In September, the ospreys leave the reservoir and south to Central and South America for the winter.

Horses Make A Difference

Although the Utes and Shoshone roamed much of this area for hundreds of years, it wasn’t until the European explorers brought horses that they were able to improve their mode of travel. With wild horses and those captured from the Spaniards, Native Americans greatly increased their mobility and range during the 18th century.

“We Have Named It Flaming Gorge”

In 1869, Major John Wesley Powell and his expedition party, floating the Green River, reached brilliant colored cliffs and named this area Flaming Gorge.

The deep red cliffs of Flaming Gorge were formed as the Uinta Mountains uplifted some 70 million years ago and the Green River held its place by cutting through the ancient rocks. Many pages of geological history have been exposed in the Uinta Mountains, as forces of nature work to carve the scenic beauty we see today.

William H. Ashley

The Ashley National Forest, of which Flaming Gorge National Recreation area is a part, was named after William H. Ashley, an early fur trader and trapper. In 1825, Ashley and his party set out to join Jedediah Smith and other mountain men who were successfully trapping beaver along the Green River.

After a nearly-disastrous boat trip down a portion of the river, Ashley traded with the Utes for horses. He crossed the Uinta Mountains and finally met with Smith and the other trappers on Henry’s Fork of the Green River. There, in the summer of 1825, some 1,000 mountain men and Indians traded, while celebrating for several days. Thus, a tradition of the rendezvous was born. It became an annual event for the next 15 years, marking a colorful chapter in Western history.

Francis Turbine Wheel
Installed June 1963 – Removed October 2005

Standing 8 feet and 6 inches tall on its side, this turbine wheel was used to generate electricity at Flaming Gorge Powerplant for 42 years. This turbine wheel, coupled to a generator, produced 7.4 billion kilowatt-hours of electricity. This would be equivalent to powering about one million households for about one year. Approximately 2.1 billion gallons of water ran through the turbine wheel, generating electricity.

The Francis Turbine Wheel is named after the inventor, James B. Francis, and is the type most widely used by Reclamation. The fast-moving water pushes against the blades of the turbine wheel, causing the runner to rotate like a pinwheel in the wind. The runner is connected to the rotating assembly of the generator by a large vertical shaft. The shaft transmits the turbine’s mechanical energy obtained from the falling water to the generator for conversion to electrical energy. When the water has moved through the turbine, it flows down the river, unchanged, to serve other needs.

Flaming Gorge Dam: The Good, the Bad & the Beautiful

When John Wesley Powell first looked out across the Green River, it was warm, silt-laden and swift. Floods scoured the area each spring, triggering the breeding cycle of many fish and creating sand and gravel bars in which the fish would lay their eggs. Flood-created marshes and backwaters also provided food and shelter for young fish, and for numerous insect-eating birds and other wildlife.

When Flaming Gorge Dam was built, it changed the life-cycle of the river. Water was released from the bottom of the dam, so it flowed cold and clear year-long. Releases fluctuated daily, and sometimes hourly, because water levels were controlled by power and storage needs rather than natural rhythms. Spring flooding was controlled. Some wildlife, especially native fish, suffered, since they were not adapted to a river controlled by a dam or to the reservoir it created. A few wildlife species benefitted. Osprey habitat was enhanced by the creation of a clear-water reservoir. Trout also thrived in the cold, clear water. In fact, the tailrace is now considered an international Blue Ribbon trout fishery and the reservoir has produced more than its share of state records for trophy fish.

May 30. The opposite wall is a vast amphitheater… Each step is built of red sandstone… The amphitheater seems banded red and green, and the evening sun is playing with roseate flashes on the rocks, with shimmering green on the cedars’ spray, and with iridescent gleams on the dancing waves. The landscape revels in the sunshine.

May 31. Today we have an exciting ride. The river rolls down the canyon at a wonderful rate with no rocks in the way we make almost railroad speed.
—John Wesley Powell, 1869

Restoring a Better Balance for Fish

More recent modifications to the dam and its management have also helped wildlife. Today, release temperatures can be regulated by taking water from any depth, which enhances trout habitat. The highly fluctuating flows for power generation are moderated by agreements which enhance habitat for native fish.

Wildlife Along the Byway:
From Moose to Marmots

You are standing in one of the richest wildlife areas in the western United States. Utah is known for roughly 600 species of birds, mammals, reptiles, amphibians and fish. About 390 of these have been found in the Uinta Basin and mountains around you. While exploring the Byway, watch for large herds of elk, mule deer and pronghorn antelope grazing within sight of the highway.

Depending on the time of year and the elevations you are in, it is also possible to see moose, Rocky Mountain bighorn sheep, golden eagles, red-tailed hawks, yellow-bellied marmots, golden-mantled ground squirrels, ravens, black-billed magpies and mountain bluebirds. In the summer, watch for ospreys; in the winter, keep an eye out for bald eagles which are most often found near water.

Dam Movement

The concrete pillar in front of you is a permanently installed base from which tiny movements in the dam can be measured. A measuring instrument is affixed to the pillar and horizontal and vertical angles determined. Several of these reference pillars are located throughout the area.

Flaming Gorge Dam

This impressive view of the dam reveals its mass and height. The dam stands 455 feet (140 meters) above the river channel. It extends below the river bottom for another 47 feet (14 meters), where it is anchored in bedrock. One million cubic yards (765,000 cubic meters) of concrete were used to build the dam and powerplant.