Pool 12 of the Upper Mississippi River extends 26.3 miles from Lock and Dam 12 in Bellevue to Lock and Dam 11 in Dubuque. Pool 12 has 12,349 acres of aquatic habitat. Pool 12 encompasses most of the natural river floodplain and is bounded by limestone bluffs for much of its length. Pool 12 has islands, side channels, and backwaters throughout most of its length. Unlike many pools, the lower reach of Pool 12 is not an open expanse of water. Pool 12 is also part of the Upper Mississippi River National Wildlife and Fish Refuge.
Navigation maps are available from this US Army Corps of Engineers website (link takes you offsite).