19th century Mississippi River

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lock , dam no. 11, north of dubuque, iowa (2007)


in 1829, there surveys of 2 major obstacles on upper mississippi, des moines rapids , rock island rapids, river shallow , riverbed rock. des moines rapids 11 miles (18 km) long , above mouth of des moines river @ keokuk, iowa. rock island rapids between rock island , moline, illinois. both rapids considered virtually impassable.


in 1848, illinois , michigan canal built connect mississippi river lake michigan via illinois river near peru, illinois. canal allowed shipping between these important waterways. in 1900, canal replaced chicago sanitary , ship canal. second canal, in addition shipping, allowed chicago address specific health issues (typhoid fever, cholera , other waterborne diseases) sending waste down illinois , mississippi river systems rather polluting water source of lake michigan.


the corps of engineers recommended excavation of 5-foot-deep (1.5 m) channel @ des moines rapids, work did not begin until after lieutenant robert e. lee endorsed project in 1837. corps later began excavating rock island rapids. 1866, had become evident excavation impractical, , decided build canal around des moines rapids. canal opened in 1877, rock island rapids remained obstacle. in 1878, congress authorized corps establish 4.5-foot-deep (1.4 m) channel obtained building wing dams direct river narrow channel causing cut deeper channel, closing secondary channels , dredging. channel project complete when moline lock, bypassed rock island rapids, opened in 1907.


to improve navigation between st. paul, minnesota, , prairie du chien, wisconsin, corps constructed several dams on lakes in headwaters area, including lake winnibigoshish , lake pokegama. dams, built beginning in 1880s, stored spring run-off released during low water maintain channel depth.



lock , dam no. 2, near hastings, minnesota (2007)



lock , dam no. 15, largest roller dam in world davenport, iowa; rock island, illinois. (1990)








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