A Fulham couple say an alley next to their home is used by drug addicts and as a toilet and claim Waitrose, which owns the passage, is indifferent to their plight.
Daniel Petit and Rebecca Bradnam say the alleyway between their Dawes Road home and Waitrose supermarket is constantly fouled by human excrement, litter and hypodermic needles.
After 10 years of blight, the couple contacted this newspaper, which first exposed the problem of the foul thoroughfare in January.
Despite promises from the supermarket to clean it, the couple say the passageway is as vile as ever.
Ms Bradnam added: "There is human waste, dog muck and vomit - it is like a cesspit. It stinks and it is almost as if the ground in the area has been permeated.
"Waitrose is very elusive, they just seem to gloss over the problem."
Ms Bradnam is unimpressed with the super-market's cleaning efforts.
She added: "Whoever sweeps the alley does not clean up vomit, it is just left."
Waitrose department manager Richard Walton said the company was discussing ways to stop the fouling with the council and the police.
He added: "We have also arranged for a contractor to come in and clear the area."
The supermarket is also calling on neighbouring shops to lock their dustbins at night.
A Hammersmith and Fulham Council spokesman said: "This passageway belongs to Waitrose, not the council, and we urge Waitrose once again to put measures in place to keep it clean."
