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41-560: The Echo Park Dam project was first proposed in 1941. Dinosaur National Monument was, at the time of its designation in 1915, a small 80-acre (32 ha) park unit focused on the dinosaur fossil beds discovered along the Green River in 1909. The monument was expanded in 1938 to 200,000 acres (81,000 ha), encompassing the canyon networks of the Green and Yampa upstream from the dinosaur quarry. The newly added areas were little known to

82-449: A compromise that eliminated Echo Park Dam and authorized the rest of the project. The Colorado River Storage Project Act became law on April 11, 1956. It stated, "that no dam or reservoir constructed under the authorization of the Act shall be within any National Park or Monument." Places on the list of National Register of Historic Places include: The Dinosaur National Monument sits on

123-474: A gravity dam is built to support the weight of the dam and all the water, it is quite flexible in that it absorbs a large amount of energy and sends it into the Earth's crust. It needs to be able to absorb the energy from an earthquake because, if the dam were to break, it would send a mass amount of water rushing downstream and destroy everything in its way. Earthquakes are the biggest danger to gravity dams and that

164-479: A monolith standing just below the confluence of the Green and Yampa, where the Green flows out of Echo Park, a broad wooded flatland walled by steep canyon cliffs. Located at the base of Harpers Point, the dam was to be a 529-foot (161 m) high concrete gravity dam . Above Echo Park, the 6,400,000-acre-foot (7.9 km) reservoir was to flood the Canyon of Lodore, extending upstream through Browns Park . The Yampa

205-650: A nearly complete skull, the lower jaw, and first four neck vertebrae. The specimen was found at the base of the Mussentuchit Member of the Cedar Mountain Formation and is the holotype for the description. Paleontologist Earl Douglass of the Carnegie Museum discovered eight vertebra of an Apatosaurus on August 17, 1909, which became the first dinosaur skeleton discovered and excavated at the new Carnegie Quarry. The area around

246-432: A problem, as they can scour dam foundations. A disadvantage of gravity dams is that their large concrete structures are susceptible to destabilising uplift pressures relative to the surrounding soil. Uplift pressures can be reduced by internal and foundation drainage systems. During construction, the exothermic curing of concrete can generate large amounts of heat. The poorly-conductive concrete then traps this heat in

287-532: A ten-dam, billion dollar Colorado River Storage Project began to arouse opposition in the early 1950s when it was announced that one of the proposed dams would be at Echo Park , in the middle of Dinosaur National Monument. The controversy assumed major proportions, dominating conservation politics for years. David Brower , executive director of the Sierra Club , and Howard Zahniser of The Wilderness Society led an unprecedented nationwide campaign to preserve

328-519: A vast area of desert land in Northwestern Colorado and Northeastern Utah. Typical of high deserts, summer temperatures can be exceedingly hot, while winter temperatures can be very cold. Snowfall is common, but the snow melts rapidly in the arid and sunny climates of these states. Rainfall is very low, and the evaporation rate classifies the area as desert, even though the rainfall exceeds 10 inches. The "Wall of Bones" located within

369-778: Is an American national monument located on the southeast flank of the Uinta Mountains on the border between Colorado and Utah at the confluence of the Green and Yampa rivers. Although most of the monument area is in Moffat County, Colorado , the Dinosaur Quarry is located in Utah, north of the town of Jensen, Utah . The nearest Colorado town is Dinosaur while the nearest city is Vernal, Utah . Originally preserved in 1915 to protect its famous Dinosaur Quarry,

410-637: The Depression under the Transient Relief Service and later under the Works Progress Administration. This work included constructing a road to the quarry, removal of overburden covering the bone-bearing strata, and building of a small, temporary museum. World War II interrupted work, but this was resumed in 1951 with the building of a small metal building over the east portion of the quarry to test whether bone

451-545: The Dinosaur Quarry building in the park consists of a steeply tilted (67° from horizontal) rock layer which contains thousands of dinosaur fossils . The preserved section is only a portion of what was originally present when Douglass made his discovery as seen on the map above. When work ceased in 1922, a portion of the quarry was left for future development. This work began as part of President Franklin Roosevelt's Civil Works Administration, which provided employment during

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492-789: The Echo Park Dam proposal was a July 22, 1950 article by Bernard DeVoto in The Saturday Evening Post , entitled "Shall We Let Them Ruin Our National Parks?" Implicitly comparing the flooding of Echo Park to the Hetch Hetchy intrusion in Yosemite, the article was picked up by Reader's Digest and saw wide circulation. The Colorado River Storage Project was proposed by the Bureau of Reclamation in

533-744: The Fremont culture is unclear. Recent theories suggest that the Fremont's lifestyle may have changed due to drought or other climate factors, dwindling natural resources, or the influence of other neighboring cultures. They left evidence of their presence in the form of petroglyphs and pictographs of human and animal figures, and abstract designs. Human figures typically have trapezoidal bodies and elaborate decorations that suggest headdresses , earrings, necklaces, or shields. The animal figures include bighorn sheep, birds, snakes, and lizards. Purely abstract or geometric designs, such as circles, spirals, and various combinations of lines, are common. Many designs in

574-800: The National Park Service in the Colorado Basin entirely omits the Glen Canyon region from its assessment, focusing instead on the Aquarius Plateau to the northwest and Monument Valley to the southeast. The Park Service had no official opinion on Glen Canyon, since it was not a Park Service unit and was tacitly excluded from Park Service plans, while the Sierra Club, focused on the fight to keep water development out of established parks, failed to realize until it

615-833: The area of what is now Dinosaur National Monument before the 14th century, with archaeological evidence dating from c. 200 to c. 1300. Archaeologists first studied and named the Fremont culture along the Fremont River in south-central Utah and have since traced it through much of the Green and Colorado River drainages. The Fremont did not build large permanent dwellings; instead, they lived in small bands within natural shelters, such as rock overhangs or shallow caves, or small villages. They consumed plant foods, such as pine nuts , berries, and cactus fruits, as well as wild game, including mule deer , bighorn sheep , smaller mammals, and birds. They also grew corn, beans, and squash, sometimes using irrigation techniques. The fate of

656-644: The bedrock below the unstable clay. The Dinosaur Quarry was reopened in Fall 2011. Gravity dam A gravity dam is a dam constructed from concrete or stone masonry and designed to hold back water by using only the weight of the material and its resistance against the foundation. Gravity dams are designed so that each section of the dam is stable and independent of any other dam section. Gravity dams generally require stiff rock foundations of high bearing strength (slightly weathered to fresh), although in rare cases, they have been built on soil. Stability of

697-442: The dam primarily arises from the range of normal force angles viably generated by the foundation. Also, the stiff nature of a gravity dam structure endures differential foundation settlement poorly, as it can crack the dam structure. The main advantage to gravity dams over embankments is the scour -resistance of concrete, which protects against damage from minor over-topping flows. Unexpected large over-topping flows are still

738-406: The dam structure for decades, expanding the plastic concrete and leaving it susceptible to cracking while cooling. It is the designer's task to ensure this does not occur. Gravity dams are built by first cutting away a large part of the land in one section of a river, allowing water to fill the space and be stored. Once the land has been cut away, the soil has to be tested to make sure it can support

779-399: The dinosaur beds as Dinosaur National Monument in 1915. The monument boundaries were expanded in 1938 from the original 80 acres (0.13 sq mi; 0.32 km ) surrounding the dinosaur quarry in Utah, to 210,844 acres (329 sq mi; 853 km ) in Utah and Colorado, encompassing the river canyons of the Green and Yampa . The plans made by the U.S. Bureau of Reclamation on

820-482: The early 1950s as an integrated plan for collecting and using the waters of the upper Colorado River. Politically, the project had the backing of the upper Colorado states: Colorado, Wyoming and Utah, as well as Arizona, who had all fought with California over water allocations from the Colorado, of which California consumed a disproportionate share. Construction of storage reservoirs high on the river system would allow

861-547: The entire monument on the Green and Yampa. Although Split Mountain Dam was to have a hydraulic height of about 100 feet (30 m), a 9,000-foot (2,700 m) penstock was planned to be built to carry water across a deep bend of the Green, taking advantage of the river's fall to create a 200-foot (61 m) head for power generation. The Split Mountain reservoir would have inundated Rainbow, Island and Little Rainbow Parks. Dinosaur National Monument Dinosaur National Monument

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902-468: The foundation's support strength: the Westergaard, Eulerian, and Lagrangian approaches. Once the foundation is suitable to build on, construction of the dam can begin. Usually gravity dams are built out of a strong material such as concrete or stone blocks, and are built into a triangular shape to provide the most support. The most common classification of gravity dams is by the materials composing

943-469: The free-flowing rivers and scenic canyons of the Green and Yampa Rivers. They argued that if a national monument was not safe from development, how could any wildland be kept intact? On the other side of the argument were powerful members of Congress from western states, who were committed to the project in order to secure water rights, obtain cheap hydroelectric power and develop reservoirs as tourist destinations. After much debate, Congress settled on

984-478: The hard rock to reveal the excavated fossil bones in-situ. In July 2006, the Quarry Visitor Center was closed due to structural problems that since 1958 had plagued the building because it was built on unstable clay. The decision was made to build a new facility elsewhere in the monument to house the visitor center and administrative functions, making it easier to resolve the structural problems of

1025-409: The main Echo Park Dam with a reservoir pool elevation of 5,570 feet (1,700 m) above sea level and a smaller afterbay dam downstream at Split Mountain, that would collect and re-regulate discharges from the main dam, assuring an even river flow. The Split Mountain pool was planned for an elevation of 5,050 feet (1,540 m). Echo Park Dam was planned for a site just downstream from Steamboat Rock,

1066-621: The monument are accessible for close viewing, along four trails in Utah, one of which is near the visitor center, and a fifth trail in Colorado. The dinosaur fossil beds ( bone beds ) were discovered in 1909 by Earl Douglass , a paleontologist working and collecting for the Carnegie Museum of Natural History . He and his crews excavated thousands of fossils and shipped them back to the museum in Pittsburgh, Pennsylvania for study and display. President Woodrow Wilson proclaimed

1107-413: The monument was greatly expanded in 1938 to include its wealth of natural history. The park's wild landscapes, topography, geology, paleontology, and history make it a unique resource for both science and recreation. The park contains over 800 paleontological sites and has fossils of dinosaurs including Allosaurus , Deinonychus , Abydosaurus , and various sauropods . The Abydosaurus consists of

1148-517: The park as well. Installed power generating capacity was to amount to 200 MW. Split Mountain Dam, 118 feet (36 m) high, was to be sited a couple of miles downstream from Split Mountain, about two miles in a straight line from the Quarry Visitor Center, or about ten river miles upstream. The pool was to back up through Whirlpool Canyon to the toe of Echo Park Dam. The two dams were to create slackwater reservoirs throughout virtually

1189-553: The position of Secretary of the Interior Oscar L. Chapman , whose department controlled both the Park Service and the Bureau of Reclamation. Drury stated in the 1950 Park Service annual report that reservoir projects would "destroy or impair the beauty and interest" of the national parks. Drury, a Republican in a Democratic administration, resigned in 1951, leading to criticism of Chapman for forcing Drury out. Drury

1230-408: The public and to the Park Service, and the Park Service initially did not oppose the dam plans, having allied itself with the Bureau of Reclamation to develop Boulder Dam National Recreation Area (later Lake Mead National Recreation Area ) and other reservoirs as public recreation facilities. The Park Service finally came out against the proposal in 1950, with director Newton B. Drury in opposition to

1271-603: The quarry building while still retaining a portion of the historic Mission 66 era exhibit hall. It was announced in April 2009 that Dinosaur National Monument would receive $ 13.1 million to refurbish and reopen the gallery as part of the Obama administration's $ 750 billion stimulus plan. The Park Service successfully rebuilt the Quarry Exhibit Hall, supporting its weight on 70-foot steel micropile columns that extend to

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1312-580: The quarry was declared a national monument on October 4, 1915. The International Dark-Sky Association designated Dinosaur National Monument an International Dark Sky Park in April 2019. The rock layer enclosing the fossils is a sandstone and conglomerate bed of alluvial or river bed origin known as the Morrison Formation from the Jurassic Period some 150 million years old. The dinosaurs and other ancient animals were carried by

1353-498: The river system which eventually entombed their remains in Utah. The pile of sediments were later buried and lithified into solid rock. The layers of rock were later uplifted and tilted to their present angle by the mountain building forces that formed the Uinta Mountains during the Laramide orogeny . The relentless forces of erosion exposed the layers at the surface to be found by paleontologists. The Fremont people lived in

1394-520: The size of Yellowstone National Park , that would have encompassed Glen Canyon and the surrounding lands. The proposal was whittled down by excluding grazing lands, and then by intervention by Utah, favoring the reservation of Glen Canyon as a reservoir site. In the 1940s and 1950s this proposal was apparently forgotten or ignored. The Glen Canyon region was a virtually unknown wilderness, not widely regarded as particularly high in scenic value. A 1946 survey of potential recreational resources undertaken by

1435-408: The structure: Composite dams are a combination of concrete and embankment dams . Construction materials of composite dams are the same used for concrete and embankment dams. Gravity dams can be classified by plan (shape): Gravity dams can be classified with respect to their structural height: Gravity dams are built to withstand some of the strongest earthquakes . Even though the foundation of

1476-770: The upstream states more control over the water and its use. In 1955, the new Secretary of the Interior Douglas McKay withdrew the Interior Department's support for the Echo Park Dam. Glen Canyon Dam was proposed from the beginning of the Colorado River Storage Project as the project's chief feature. Secretary of the Interior Harold Ickes had proposed the establishment of Escalante National Monument in 1936, at 2,450 square miles (6,300 km) twice

1517-407: The weight of the dam and the water. It is important to make sure the soil will not erode over time, which would allow the water to cut a way around or under the dam. Sometimes the soil is sufficient to achieve these goals; however, other times it requires conditioning by adding support rocks which will bolster the weight of the dam and water. There are three different tests that can be done to determine

1558-583: Was abundant enough to warrant a larger, more permanent building. This more permanent building was erected in the mid-1950s as part of the National Park Service Mission 66 plan. The architectural design was high controversial for its ultra-modern use of glass, steel and concrete ramp that spiraled around a cylindrical office tower. The building opened at the dedication ceremony on June 1, 1958. The design had two levels and abundant natural light so that visitors could watch technicians remove

1599-427: Was succeeded for eight months by Arthur Demaray , then by Conrad Wirth . Wirth took a less confrontational approach, partly under orders from Chapman to make the disagreement less public. Wirth was an advocate of public recreation lands associated with Reclamation projects, and suggested that Echo Park could become a National Recreation Area once flooded with a reservoir. The first widely published public reaction to

1640-410: Was to be flooded as well to Lily Park. Roughly half of Steamboat Rock's height would have been underwater, along with archeological sites, caves and wilderness valleys. A Park Service report on the dam's effects on the monument called it a "lamentable intrusion" with "particularly deplorable effects" on wilderness and geological features in the monument. Electric power transmission lines would intrude into

1681-410: Was too late that Glen Canyon possessed scenic and wilderness value even greater than Dinosaur. Sierra Club executive director David Brower 's assent to a suggestion that the proposed Glen Canyon Dam be raised led Brower's critics to argue that he effectively sacrificed Glen Canyon to save Dinosaur. Brower considered the trade to be his biggest mistake. The Echo Park project actually involved two dams:

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