I looked on the Mario maps KATEX mentioned, ( thanks for that KATEX ). That land on Hopwood St is shown as having a 'pump' in the middle of it which is what one or two locals said years ago. I presume that is a well or something and as 'forgotten' now that would account for the water pouring down Hopwood St. Perhaps there is a blocked underground pipe or something.
Anyway MargaretR : it will likely be a lot of work to dig it out and 'taste' it. I would have thought if it is as old as it appears to be, the water was probably from a reliable and clean source originally, but who knows what abandonment has done to it....
All this has got me very interested in the 'underground' Accrington we don't know about! There is a whole row of houses I know of that is sinking into the ground......wonder if they are on an old mine-shaft/tunnel or something....& on that note..an old man told my mother there are tunnels all the way from here to Blackpool that were dug as collieries joined up to others. Sounds a bit far fetched I think..