In the case of sewers or drains constructed in any street or road dividing the municipalities, to connect with joint outlet or trunk sewers or disposal plants, the assessment upon all lands and real estate which at the time of making such assessment front or abut on or are situate in the vicinity of the line of such sewer or any other sewer already constructed and connected directly or indirectly therewith, whereby a direct tapping or drainage benefit is or may be secured, shall be collectible at once, and where such benefit is prospective only, depending upon the construction of any other and connecting sewer not yet built, such assessment shall be collectible and bear interest only from the time when the assessment to be made for benefits conferred upon such land and real estate by the construction of such other sewer along the line of which such lands and real estate fronting or abutting or in the vicinity of, shall be confirmed and collectible.