The six mile square that would become Eau Pleine was first surveyed in September of 1851 by a crew working for the U.S. government.

In September 1853 another crew marked its section corners, walking through the woods and wading the streams, measuring with chain and compass.

[5][6] When done, the deputy surveyor filed this general description: The greater portion of the surface of this township is gently rolling, the ballance is flat level land with but little swamp.

The current is generally quick, with frequent small rapids, and a hard bottom of stone and gravel.

The small streams run into the Big Eau Plaine: they have mostly a quick current, a hard gravel bottom and low banks covered with Alders.

[7]The name Eau Pleine is derived from the French phrase meaning "full water" or "stock river".