Minn. Stat. § 505.10: MAJOR STREET PLAN.

In order to exercise the power conferred under sections 505.09 to 505.13, the board of county commissioners shall prepare a comprehensive major street plan of the district involved, which plan shall be designated and adopted as the official major street plan of the areas adjoining the city of .................... Such plan may, from time to time, be amended, extended, or amplified. In the preparation of the major street plan and in the administration of the powers herein conferred, the board of county commissioners may avail itself of the assistance of the city planning commission of the city of the first class adjoining the areas involved.