Apart from a foray to Reams Station in mid-July, the regiment was busy with the building of entrenchments until July 26, when the Fifty-third moved with the brigade to the right and north of the James River, to take part in the First Battle of Deep Bottom. It returned to the Petersburg siege lines until August 12, when the command again returned to the left bank of the James where it was engaged with Confederate outposts at the Second Battle of Deep Bottom. On the 21st, the regiment re-crossed the James and the Appomattox Rivers and passing in rear of the army to the extreme left of the line, commenced demolishing the Weldon Railroad near Ream's Station. Five miles had already been destroyed when the Confederates attacked in force and a line of battle was hastily formed to repel his advance and protect the working parties. The first charge was repulsed, but the next charge struck with overpowering force and the line wavered. Exhaustion, illness and low morale all contributed to the near disaster for the Second Corps at the Second Battle of Ream's Station, forced to abandon the field and retire to the lines in front of Petersburg.