Skirmish at Dam No. 5

On October 7, 1861, Thomas “Stonewall” Jackson was promoted to Major General. Two weeks later he received a letter from Judah P. Benjamin the Confederacy’s Secretary of War that he had been appointed the new head of the 6,000 square mile Valley District of the Department of Northern Virginia. His District would be headquartered in Winchester. However, initially his command would consist of only three brigades of state militia led by Brigadier Generals James Boggs, G.S. Meem and J. H. Carson (1,461 infantry and 225 cavalry). His men were far too inexperienced and far too few to cover the vast territory. Jackson turned to Virginia Governor John Letcher for help, and he was instrumental in getting Jackson’s former brigade, the Stonewall Brigade, reassigned to his district, as well as Turney Ashby’s 7th Virginia Cavalry.

The War Department selected Richard Garnett to command the Stonewall Brigade. In addition, Benjamin also ordered Brigadier General William Loring and his 6,000-man Army of the Northwest to join Jackson from the Alleghenies. Brigadier General William Taliaferro’s brigade (3rd AR, 23rd and 37th VA, and the 1st GA) was the first to leave departing McDowell on November 29th and arriving in Winchester on December 8th. While waiting for Loring’s force to arrive, Jackson decided to try and damage the Chesapeake and Ohio Canal on the north side of the Potomac seven miles upriver from Williamsport at Dam No. 5. With the recent disruption of rail traffic on the Baltimore and Ohio railroad the canal was an even more important supplier of coal, lumber, hay and oats for Washington. Jackson assigned Captain William McLaughlin to break the dam there with a force of 400 infantry, and four guns of the Rockbridge Artillery. The dam regulated the water level in lock #46 of the Chesapeake and Ohio Canal there. Without the dam the lock would not function and without the lock the canal could not operate.

McLaughlin arrived at Potomac Heights on the Virginia side of the dam on December 7th. The guns opened fire on the dam which was defended by two or three companies of the 12th IN and one company of the 13th MA. The Federals were armed with old smoothbore muskets that could not reach the Virginia shoreline, so McLaughlin moved his guns down to the riverbank. However, the Confederate Artillery were equally infective at damaging the dam as the Federals were trying to shoot across the river. Overnight Colonel Samuel Leonard of the 13th MA took a canal boat downstream to Williamsport and picked up a company of his regiment that were armed with Enfield rifled muskets. When the artillerymen returned the following morning Leonard’s new company opened fire wounding two men and the Confederates fled up the bluff. They returned after dark to move the guns back to the top of the ridge. On the 9th a detachment of Confederates captured a group of eight men from the 12th IN on the VA side of the river that were reconnoitering to determine if the Rebels were still there. They then proceeded to dig a ditch around the southern abutment to try and wash away the dam. They completed their work after sunset. However, in the interim, the water level in the river fell and once again the dam was undamaged.

When Jackson learned of McLaughlin’s failure he decided to try again with a larger force. This time Jackson would personally lead an operation that would include the Stonewall Brigade, the entire six guns of the Rockbridge Artillery, Ashby’s cavalry, and J. H. Carlson’s militia brigade. Most of the force would engage in feints designed to draw as many Federals away from the dam itself or prevent their reinforcement. A small work party commanded by Captain Raleigh Colston and his brother William Colston from Company E of the 2nd VA would then destroy the dam by hand with crowbars, pick axes and shovels. In the days prior to leaving Jackson sent scouts to the area spreading misinformation that the Confederates would be attacking Romney. On the morning of the 16th they left Winchester camping two miles from Martinsburg. That evening Jackson ordered William Colston to head to the bluffs overlooking the dam with four men and remain there the entire day of the 17th scouting to determine the size of the Federal force. He returned that evening and reported that no Yankees were there. Carson’s brigade was sent to Fallings Water across the Potomac from Williamsport to create a diversion. The Colston brothers and their 3-company work party headed to the dam in the dark and arrived around midnight. Three hours later the rest of Jackson’s force broke camp and headed for the dam. The work party snuck out onto the dam to try and destroy a portion of it but after a few hours they were detected by Union pickets on the Maryland shoreline at daybreak. The pickets fired on Colston’s men until Jackson’s artillery with Lieutenant William Poague directing several of the guns opened fire on them causing the sharpshooters to flee. Battery E of the 1st PA Artillery returned fire and Jackson ordered Colston’s demolition team out of the freezing water and back to shore.

Jackson organized new work parties from the 27th and 33rd VA and sent them back into the icy waters after dark on the 18th until just before dawn on the 19th. Union forces fired on them as soon as they appeared from the shoreline. Union Major General Nathaniel Banks realizing Jackson’s true target was the C&O Canal sent reinforcements there from Frederick. Despite spirited cannon and musket firing from both sides of the Potomac little damage was done. Colston’s men were back in the water again just after sunset until just before dawn on the 20th. They finally succeeded in breaching the dam. Jackson convinced that the break was wide enough to disrupt the function of the canal ended the expedition his men referred to as the dam[n] trip and ordered a return to Winchester. However, Federal engineers repaired the breach and by nightfall on the 21st the canal was once again fully operational.

Images from the Chesapeake and Ohio Canal National Historical Park at Dam No. 5 are shown below.