Management of water surface elevations at 27 dams affects much of the floodplain habitat in a 653-mi stretch of the Upper Mississippi River (UMR) between St. Louis, Missouri, and Minneapolis, Minnesota. In 1930, Congress authorized most of these dams to maintain a 9-foot navigation channel. This report provides a systemic overview of current operating plans at dams on the UMR and analyzes historical data to determine how well the operating plans are being met. Water level elevations at all 27 dams on the UMR are regulated as a function of discharge, although plans are specific for each dam. The U.S. Army Corps of Engineers strives to maintain a target water level at a specific location in a pool (control point) over a specific range of discharges. In any particular pool, the target water level and control point may change as the discharge changes. Control points can be located anywhere within a pool, but they are usually near the mid-point of the pool or at the pool's downriver end. Difficulties in meeting targets are caused by winds, local rainfall events, ice dams, and rapidly fluctuating discharges from tributaries having upstream reservoirs used for peaking hydropower. Water level measurements and discharge estimates were used to assess the amount of time water levels were near their targets during the navigation seasons of 1980 through 1990, inclusive. Water levels were within their target window an average of 72.5% of the time for 25 dams analyzed. When target windows were expanded by �0.5 ft, water levels were in the target window 99.0% of the time. Yearly water level fluctuations were found to be caused mostly by discharge and were usually less after dam construction. Yearly and daily mean water level fluctuations varied with location within a pool, generally decreasing downriver.