Surface-applied manures are of particular concern in the Southern Piedmont (USA) because of a high concentration of broiler production. As these manures can contribute to P in runoff, a study was conducted to examine the water conservation potential of mechanical aeration of grasslands which has potential to reduce P transport by increasing infiltration of rainfall and binding of P with clay minerals. The effects of four aeration treatments (disk aeration perpendicular to the slope, aeration with cores, aeration with spikes, and no aeration treatment) on the export of total Kjeldahl P (TKP) and dissolved reactive P (DRP) in surface runoff from grasslands with two nutrient treatments (broiler litter and no manure) were examined. Plots (0.75 x 2 m) were established on a Cecil soil series with mixed tall fescue/bermudagrass vegetation on 8 to 12% slopes. Simulated rainfall was applied at a rate of 75 mm h^-1 to evaluate baseline conditions. Plots were then aerated and manures applied at a rate of 30 kg P ha^-1, prior to additional rainfall simulations. Results indicate core aeration decreased TKP and DRP loads (P < 0.05) from applied broiler litter by 46 and 62%, respectively. Because Cecil soil is common in pastures receiving broiler litter in the Southern Piedmont, these results suggest that core aeration could have a widespread impact on water quality in the Southern Piedmont region.