All sewer, paving and other special assessments heretofore attempted to be authorized by any city of the fourth class, under or pursuant to the provisions of chapter 24 of Act No. 215 of the Public Acts of 1895, as amended, the amounts of which special assessments are according to such attempted authorizations to be divided into not more than 10 installments, 1 of which it is proposed shall be collected each year, are hereby declared to be confirmed by the common council, a valid lien upon the respective lot or parcel of land assessed; the provisions of section 3122 of the Compiled Laws of Michigan of 1915 notwithstanding: Provided, That the proposition to authorize any such special assessments has been submitted to the electors of the city at any election duly and legally held and has received the affirmative vote of at least 2/3 of the electors voting thereon.