The LMRWD was principally established to be a legal entity for providing local participation to the U.S. Army Corps of Engineers (USACOE) to construct a navigation channel within the Minnesota River. With this purpose in mind, a nine-foot channel was developed in cooperation with the USACOE.

Today, the LMRWD is still actively involved in the maintenance of the channel. The statutes and rules affecting watershed districts and watershed management organizations have changed since the inception of the LMRWD. These changes have broadened the role that watershed districts play in water resource management.

From the original petition:
That the formation, and establishment of the proposed District is necessary and would be conducive to the public health and public welfare in and upon its formation the District shall cooperate with, aid, and assist the State or Federal Government and all subdivisions of agencies thereof in carrying out the purposes of the District; that the timely establishment of said Watershed District will allow the immediate inception of the plans of the U.S. Army Corps of Engineers for the diversion and improvement of the watercourse of the Minnesota River within the District so as to provide water capacity for barges and heavy commercial river transportation on said river throughout the District, thus providing a water route for incoming and outgoing commodities of trade to serve the general agricultural and industrial areas adjacent to and within the trade area tributary to the District, all of which are of great benefit to the vast area of this State…