The legislature finds and declares that the local governmental units within the metropolitan area are interdependent, that the growth and patterns of urbanization within the area create the need for additional state, metropolitan and local public services and facilities and increase the danger of air and water pollution and water shortages, and that developments in one local governmental unit may affect the provision of regional capital improvements for sewers, transportation, airports, water supply, and regional recreation open space. Since problems of urbanization and development transcend local governmental boundaries, there is a need for the adoption of coordinated plans, programs and controls by all local governmental units in order to protect the health, safety and welfare of the residents of the metropolitan area and to ensure coordinated, orderly, and economic development. Therefore, it is the purpose of sections 462.355, 473.175, and 473.851 to 473.871 to (1) establish requirements and procedures to accomplish comprehensive local planning with land use controls consistent with planned, orderly and staged development and the metropolitan system plans, and (2) to provide assistance to local governmental units within the metropolitan area for the preparation of plans and official controls appropriate for their areas and consistent with metropolitan system plans.