Section 5. A planning commission established hereunder shall make careful studies of the resources, problems, possibilities and needs of its district and, on the basis of such studies, shall prepare a comprehensive plan of development or a schematic study plan of such district or of such part or parts thereof as the commission may deem necessary and in such plans shall make such recommendations for the physical, social, governmental or economic improvement of the district as in their opinion will be in the best interest of the inhabitants of the district. Such plans and recommendations shall concern, among other things, the general use of the district, including land use, principal highways and expressways, bridges, airports, public utilities, public facilities, parks, recreational areas, public institutions and such other matters as in the opinion of said commission will be beneficial to the district and will promote with the greatest efficiency and economy the coordinated development of the district and the general welfare and prosperity of its people. Before the adoption of any such regional plan or a portion thereof, the district planning commission shall hold at least one public hearing thereon, notice of the time, place and subject of which shall be given. Written notice of such hearing shall be given to each planning board, board of selectmen, and city council. Notice of the time, place and subject of the hearing shall be published at least once in a newspaper having substantial circulation in the region at least ten days before such hearing. Adoption of such plan or portion thereof shall be by a majority vote of the representatives of the district planning commission. Such plan may be amended from time to time in the same manner as hereinbefore provided. A copy of the plan adopted by the commission or any amendments thereto signed by the chairman shall be filed with the town clerk of each member municipality not more than thirty days after commission action. Such plan or portion of a plan shall be a public record. Such district planning commission shall also assist the planning boards of the several cities and towns within the area of its jurisdiction in applying any district plans and recommendations so adopted to the local board's area of jurisdiction.

Such planning commission shall report annually to the city councils and town meetings of the cities and towns within its district, showing the status of its plans and recommendations. Such plans and recommendations shall be advisory only.