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Drainage water management (DWM) is currently being proposed as a BMP for reducing nutrient export from drained cropland in the US Midwest to the Mississippi River and the Gulf of Mexico. The effectiveness of the practice in the Midwest has not been well documented. We conducted a simulation study using the hydrologic model, DRAINMOD, and the carbon and nitrogen model, DRAINMOD-N II, to evaluate the performance of DWM across the US Midwest. Thorp et al (2008), used the RZWQM-DSSAT models, calibrated for a corn and soybean production system on a subsurface drained IOWA soil, to simulate the performance of DWM using 25-year climatological data from 48 locations across the Midwest. We used DRAINMOD-DRAINMOD-N II models, calibrated for the same conditions, to simulate the performance of DWM at the same 48 locations. Simulation results showed that DWM reduced annual subsurface drainage by 30% and annual N drainage losses by 32%, on average over the 48 sites. DWM was most effective in reducing drain flow and N drainage losses for the south and southeast locations. Highest simulated reductions in drain flow (45%) and N drainage losses (47%) occurred in Memphis, Tennessee. DWM was least effective for the northwest locations. Lowest simulated reduction in drain flow of 19% occurred in both Sioux City, Iowa and Sioux Falls, South Dakota. Lowest simulated reduction in N drainage loss of 12% occurred in Fargo, North Dakota. Simulated crop yields RZWQM-DSSAT showed a similar trend but predicted substantially higher reductions in both drain flow (35-68%) and N drainage losses (33-51%). DRAINMOD-simulated crop yield indicated a slight increase of the regional average of corn and soybean yields because of implementing DWM (less than 1.5%), suggesting that the yield benefits of DWM cannot solely be used to effectively promote the practice among producers.