Abstract: An adapter for a fluid conduit comprises a stepped diameter tubular member having an enlarged end portion with a plurality of piercable recesses formed thereon, a generally cup shaped obturator, and a removable sieve disposed therein. The recesses formed around the outer periphery of the enlarged end portion can be selectively pierced so as to form fluid passages with the perforated end portion acting as a filter for drainage water entering the adapter. The open end of the adapter and any perforations formed thereon can be closed off by inserting the cup shaped obturator therein. The sieve is similarly provided with piercable recesses thereon and can function as a secondary internal filter. A further fluid conduit can subsequently be connected to the adapter by inserting an end thereof into the adapter until abutment with the inner shoulder therein is reached.