'This water is not from Wapping'

Having done a bit of research...on this site and others,I need to confirm a particular episode..with whom ever reads this and can assist. For starters I think the episode of "Till Death us Do Part" is "Holiday to Bournemouth" made (according to IMDb)on the 27th of September 1972 or broadcast on that date. I saw this episode years ago. I know Alf and the "siily moo" were on holidays at some seaside "resort"...!! In the episode Alf and Else wander down to the beach...which is appropriately grey and overcast. Alf sensing that "the moo" is suitably over-awed with the experience...explains that the vast expanse of water she sees before her is actually from 'Wapping'.In a rather daring feat this is done in a long shot...the camera too far back to see any facial expressions. When most comedy is shot in close...bang bang...cut to the line and cue the laugh track. The camera then 'watches' as Alf exits the shot to left.

After a very long pause...the camera still in place behind "the moo" who remains in an unchanged posture...captures what could be the line of the series....."THIS WATER'S NOT FROM WAPPING...!!! 'Simply Brilliant' If this is the episode then I will buy it from my long suffering ABC shop in Australia...if they can get it in.