Arkansas River Channel Capacity and Riparian Habitat Planning Study

Home Browse Search

1 � ARKANSAS RIVER. FROM OTERO/PUEBLO COUNTY LINE TO JOHN MARTIN RESERVOIR CHANNEL CAPACITY AND RIPARIAN HABITAT PLANNING STUDY 1 2. GENERAL BACKGROUND AND SETTING 2.1 JOHN MARTIN RESERVOIR PROJECT John Martin Dam is located on the Arkansas River in Bent County, Colorado, near the villages of Hasty and Caddoa. John Martin Dam is 58 river -miles upstream from the Colorado- , Kansas state line and is approximately 39.4 river -miles downstream from La Junta and approximately 17.9 river -miles downstream from Las Animas. ' The Caddoa Darn and Reservoir Project, renamed in June 1940 to John Martin Dam and Reservoir Project, was authorized by Congress in the Flood Control Act of 1936 (Public Law 74- 738) as amended by the Flood Control Act of 1938 (Public Law 75- 761)(USACE 1947:1). The legislation authorized John Martin Dam and Reservoir to be operated for flood control and conservation storage of irrigation supply. The Flood Control Act of 1965 (Public Law 89 -298) further authorized the establishment of a permanent pool not to exceed 10,000 acre -feet for fish ' and wildlife and recreational purposes. Construction at the John Martin Project began in 1939 with the relocation of approximately 20 miles of the Atchison, Topeka, and Santa Fe Railway tracks (USACE 1948:5), today known as the Burlington Northern and Santa Fe Railway. Construction work on the dam began in August, 1940, but work was suspended in the spring of 1943 due to World War II (USACE ' 1943:23). However, water diversion through the sluicing conduits of the concrete dam began on November 30, 1941, and storage in the reservoir was initiated in December 1942. Management of river flows and operation of the reservoir officially began on March 11, 1943 (USACE 1943:25, 1948:3 -4, 1999:2). Construction resumed in the spring of 1946 and the project was completed in October 1948. ' At 3870 feet, maximum water surface elevation (top of flood control pool), the reservoir is 14.8 miles long with an average width of about 1.9 miles, the surface area is 17,151 acres and storage capacity is 605,115 acre -feet. Storage capacity at the top of the conservation pool ' (elevation 3,851 feet) is approximately 335,693 acre -feet (USACE 1983x:2 -2; 1999:2). The majority of the water that reaches John Martin Reservoir is derived from snowmelt and rain that originates in the mountainous upper portion of the Arkansas River drainage basin. Upon leaving the mountains, this moisture flows via the Arkansas River and it's two primary tributaries, Fountain Creek and the Purgatoire River to John Martin Reservoir. Other flows that travel via the Arkansas River channel through the study area to John Martin Reservoir include flows such as transmountain diversions, ground water including that that originates from municipal, commercial, private, and irrigation wells, and surface water drainage from plains thunderstorms. Water temporarily stored at the Bureau of Reclamation's Pueblo Reservoir, completed in 1974, is transported down the Arkansas River channel to specific users including 5