124Notwithstanding that a sufficient petition is presented against a proposed work, the council may by by-law passed by unanimous vote of the whole council
(a)
declare a work to be necessary or requisite in the general interest of the locality in which it is to be made,
(b)
authorize and direct the undertaking of such work, and
(c)
order that the cost thereof or such portion of the cost as may be fixed by a general by-law shall be raised by special frontage assessment.