No building or structure, except one- or two-family dwellings and their accessory buildings, shall be erected, enlarged or changed in use, except in conformity with a site plan bearing an endorsement of approval by the Planning Board. Said site plan shall show the owner of record, location, zone boundary lines, easements, or other legal restrictions, exact location of building(s) on the lot with side, front and rear dimensions, lot dimensions, topography, adjacent public ways, location of off-street parking, lighting, utility systems, surface drainage, traffic flow, location and nature of open spaces with specific notations as to landscaping, locus plan, and other details deemed necessary by the Planning Board. Upon written request of the applicant, the Planning Board may waive or substantially reduce the site plan submission requirements for projects having limited or minor impacts consistent with the purposes of this bylaw.