On This Date in Minnesota History: April 18

April 18, 1965 – The St. Croix River crested at 94.10 ft. at Stillwater on this date, the highest recorded river level.

http://projects.wchsmn.org/reference/events/1965-flood-crest/ 

On Easter Sunday April 18, 1965 floodwaters of the St. Croix River crested here at 694.07 ft above sea level, highest stage ever recorded at this point, and 19 ft above normal. A mile-long dike built by hundreds of volunteer workers, including teenage boys and girls and inmates of the state prison, prevented the flood waters from inundating the business district of Stillwater.

Photos taken by Pamela J. Erickson. Released into the public domain April 18, 2014,
as long as acknowledgement included.