Morrow Point Dam
Morrow Point Dam is located 12 miles (19.3 kilometers) downstream of Blue Mesa Dam in a steep and narrow reach of the Black Canyon. Completed in 1968, Morrow Point Dam was the first thin-arch, double curvature concrete dam built in the United States. Double-curvature means that the dam not only curves from left to right, it also curves from top to bottom. Morrow Point stands 468 feet high (143 meters) from the streambed, with a crest length of 724 feet (220 meters), and contains 365,180 cubic yards (279,200 cubic meters) of concrete.
The primary purpose for Morrow Point Dam is to store water for hydroelectric power generation but it also provides for irrigation, limited recreation, and flood control by regulating the river. The powerplant at Morrow Point was the first powerplant constructed underground by Reclamation and is one of only a few in the United States. The powerplant chamber is tunneled into the canyon wall in the left abutment about 400 feet (122 meters) below the ground surface. Morrow Point Powerplant contains two generating units with a total capacity of 165 megawatts.The reservoir behind Morrow Point Dam is formed between the narrow canyon walls and extends to the powerplant discharge point at Blue Mesa Dam. When full, Morrow Point Reservoir’s elevation is 7,160 feet (2,182 meters) above sea level and has a capacity of 117,190 acre-feet (145 million cubic meters) and a surface area of 817 acres (331 hectares). When the capacity of the penstocks and outlet pipes is exceeded, water from the reservoir can be released through the four spillway openings near the top of the dam and fall freely more than 350 feet (107 meters) to the stilling basin at the base of the dam.