She was constructed in Seattle, Washington; however, she spent most of her working career on the East Coast of the United States, primarily at Norfolk, Virginia, and Philadelphia, Pennsylvania.

Ordered to the Atlantic Fleet, Arapaho departed Mare Island, California on 25 February 1918 and, after transiting the Panama Canal, reached Norfolk, Virginia on 6 April.

Assigned to the Atlantic Fleet Train, Arapaho towed target rafts and barges and performed routine mooring buoy maintenance at Hampton Roads, Virginia, and occasionally ranged with the fleet to Guantanamo and Guayancanabo Bays, Cuba, and Narragansett Bay, Rhode Island.

During the first year of operations out of her new home port and yard, she was classified as AT-14 during the fleet-wide assignment of alphanumeric hull numbers on 17 July.

She remained in reserve there – reclassified, while inactive, as a yard tug YT-121 on 27 February 1936 – until struck from the Naval Vessel Register on 22 December.