Chouteau Lock & Dam

Chouteau Reservoir extends for 18.7 miles (30.1 km) to the next system on the Verdigris River, Newt Graham Lock & Dam. Its surface covers 2,270 acres (9.2 km²). Normal capacity of the reservoir is 23,340 acre feet (28,790,000 m³). Its drainage area is 240 square miles (620 km²)[5] The lock chamber, like all chambers on the MKARNS, is 110 feet (34 m) wide by 600 feet (180 m) long.[4] The lift is 21 feet (6.4 m)[6]

The Chouteau Dam is gravity type, of earthen construction. Built on a rock foundation, its height is 53 feet (16 m), and length is 11,690 feet (3,560 m). The maximum discharge rate is 155,000 cubic feet per second (4,400 m³/s).[5]

The "pintle ball", a vital piece of equipment for the Chouteau Lock, was found to be damaged and in need of total replacement during a routine dewatering of the lock in 2009. This required obtaining an identical replacement, dewatering the lock again, lifting the gate, removing the old ball and installing its replacement, then refilling the lock Such an operation had never been attempted by the Tulsa District of the U.S. Army Corps of Engineers (ACE). Complicating the operation was the fact that there were no plans or drawings to show how the work should be done, and there were no spare pintal ball parts available. The replacement would have to be designed and constructed anew. Since installing the device would require closing the lock to traffic for a minimum of three weeks, scheduling was critical to minimize costs. The ACE planned to close the lock and start the dewatering on August 27, 2012. Reopening the lock to normal traffic was scheduled for September 6, 2012.[8]