 By October 7, Polk's forces had fallen back to the town of Perryville.The dry summer of 1862 had left water in short supply, and when the Union troops learned of water in Perryville's Doctor's Creek, they began to move on the Confederate position.Bragg shared Smith's assumption that the bulk of the Union attack would be directed at Lexington and Frankfort, and ordered Polk's forces to attack and destroy the approaching Union force before proceeding to Versailles to meet Smith.