Such commission is authorized, unless otherwise provided by ordinance adopted by the municipality, to prepare and file surveys, maps or plans of proposed highways, streets, sidewalks or the relocation, grade, widening or improvement of existing highways, streets or sidewalks, or of any building or veranda lines proposed as herein provided, in the office of the town clerk of such municipality, provided such map or plan after completion shall have been approved at a meeting of the commission called for the purpose. Such map or plan shall have inscribed thereon the following: “Recommended by planning commission” and shall bear the date of such recommendation and be signed by the chairman or secretary. Such commission shall, upon the filing of such survey, map or plan, give notice to each record owner and to each mortgagee of record of land included in such survey, map or plan, by mail and by advertisement in a newspaper of general circulation in such municipality, of such filing and of the place within such municipality where, and the time, not less than ten days after such mailing and publication, when, such commission shall hear any person claiming to be affected thereby. Such commission, after such hearing, may approve and adopt such map or plan, and may make assessments of benefits accruing to and damages sustained by any person owning land included in such survey, map or plan, and shall give notice of such benefits and damages to mortgagees of record of such land. Any assessments of benefits so made shall, from the time of the completion of such work, constitute a lien against the property affected, which lien shall take precedence of all other encumbrances except taxes and other municipal liens or encumbrances of earlier date. Such liens may be continued by filing with the town clerk for record in the land records of such municipality, within ninety days after such assessment has been made and notice thereof given to the person or persons affected thereby, a certificate of such lien signed by the secretary of such commission, which lien may be enforced in the same manner as is provided for the enforcement of tax liens. Upon the adoption of any such survey, map or plan which takes an easement for public use over any parcel of land, a notice of the taking of each such easement and a description of the easement shall be recorded in the land records of the town in which such land is located, in the names of the owners of record, before such easement becomes effective. Such commission may change any survey, map or plan so made and filed by it, at such time and in such manner as it deems necessary, and shall thereupon file a survey, map or plan of such change, inscribed as hereinbefore provided, with the town clerk of such municipality. Notice by mail of such change shall be given by such commission to each record owner and to all persons having a recorded mortgage interest in land affected thereby and by advertisement as in the first instance and the subsequent proceedings shall be as provided in the case of an original filing.