USS Roanoke (ID-1695)
 The third USS Roanoke was the Southern Pacific freighter El Dia temporarily converted for planting the World War I North Sea Mine Barrage. Newport News Shipbuilding and Dry Dock Company launched El Dia at Newport News Virginia on 30 August 1911 for service between New York City and Gulf of Mexico seaports of New Orleans and Galveston Texas. The United States Shipping Board took control of the ship from Southern Pacific Steamship Company in 1917.