Queen's Dock is still this bright orange ...

There's "a bit of a dispute" about what it is, where it's coming from and who is going to pay to clean it up.
[IMO - it is Ferric oxide ie rust from old mine workings, probably coal. The water is draining into Corkickle Tunnel and then Bransty Beck before entering the Harbour / Marina. tbh, I think that the Environment Agency should sort it out asap - a reed bed system, but where ? - and claim some of the costs back from the Coal Authority, Network Rail etc. when the final costs are known, Previously, it would appear that the ballast in Corkikcle Tunnel was acting as a filter, so maybe the quickest solution would be for Network Rail to relay the track in the tunnel with clean / recycled ballast]