From Dictionary of American Naval Fighting Ships, Vol. VI (1976), pp. 18

A river in Minnesota.

(LSM(R)-521: dp. 1,289 (f.), l. 211'5", b. 34'5", dr. 9'9" s. 12 k., cpl. 140, a. 1 5", 4 40mm., 8 20mm., 4 4.2" mortars,10 5" rocket launchers; cl. LSM(R)-501)

LSM(R)-521 was laid down 5 May 1945 by Brown Shipbuilding Co., Inc., Houston Tex., launched 9 June 1945, and commissioned 1 August l945, Lt. Abram E. Manell in command.

After shakedown and training operations, LSM(R)-521 entered the Atlantic Reserve Fleet in March 1946. Named Rainy River 1 October 1955, she was struck from the Navy list 1 October 1958, and sold in 1959.