Lock and Dam No. 12

Lock and Dam No. 12
Lock and Dam No. 12 on the Mississippi River. View is upriver to the north.
Location	Bellevue, Iowa / Hanover Township, Jo Daviess County, Illinois, USA
Coordinates	42°15′41.08″N 90°25′12.47″W / 42.2614111°N 90.4201306°W / 42.2614111; -90.4201306
Construction began	1934-1939
Opening date	May 13, 1939
Operator(s)	U.S. Army Corps of Engineers, Rock Island District
Dam and spillways
Impounds	Upper Mississippi River
Length	8,369 feet (2,550.9 m)
Reservoir
Creates	Pool 12
Total capacity	92,000 acre⋅ft (0.113 km3)
Catchment area	82,400 sq mi (213,000 km2)
Lock and Dam No. 12 Historic District
U.S. National Register of Historic Places
U.S. Historic district
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Location	401 N. Riverview St., Bellevue, Iowa
Area	101.7 acres (41.2 ha)
Built	1939
Architect	Edwin E. Abbot
Architectural style	lock and dam
MPS	Upper Mississippi River 9-Foot Navigation Project MPS
NRHP reference No.	04000172[1]
Added to NRHP	March 10, 2004

Lock and Dam No. 12 is a lock and dam located on the Upper Mississippi River at Bellevue, Iowa, United States. The movable portion of the dam starts at the locks adjacent to the Iowa shore and is 849 feet (258.8 m) long, consisting of seven tainter gates and three roller gates. It connects to a 200-foot (61.0 m) storage yard and continues toward the Illinois shore with a 2,750-foot (838.2 m) non-submersible dike, a 1,200-foot (365.8 m) submersible dike and a 3,130-foot (954.0 m) non-submersible dike. The non-submersible sections are separated from the submersible section with two 120-foot (36.6 m) transitional dikes. The main lock is 110 feet (33.5 m) wide by 600 feet (182.9 m) long. There is also an incomplete auxiliary lock.^[2] In 2004, the facility was listed in the National Register of Historic Places as Lock and Dam No. 12 Historic District, #04000172 covering 1,017 acres (4.1 km²), 1 building, 3 structures, and 4 objects.