The adoption of this Zoning Ordinance shall have the force and effect of repealing all presently existing Zoning Ordinances and regulations and amendments thereto, heretofore adopted by the City of Watertown. This Zoning Ordinance and the repeal of all presently existing Zoning Ordinances and regulations heretofore in force shall not affect any act done, any right accrued or any penalty or liability incurred or any suit, prosecution or proceeding pending at the time this Zoning Ordinance becomes effective.