Around 300 loaves of bread, still wrapped in plastic, were discovered on Thursday afternoon dumped in Southmere Lake.
It took “several hours” for three volunteers from the Peabody Canals team to fish the loaves out of the water.
A spokeswoman from Peabody said the incident had been reported to the organisation’s enforcement team so the environment agency could be notified.
“Unfortunately there are some instances of dumping that take place, but never anything quite like this,” she told the Standard.
She said there was a brand name on the packaging but because an investigation was ongoing she could not release the name of the company.
The spokeswoman added they did have a van registration number in connection with the incident.
The ThamesmeadNow Twitter account posted a photo of the cleanup, writing: “Canals Team spent all day yesterday cleaning up one of our lakes, today we found over 300 mouldy loaves still in plastic wrapping dumped in the same lake. .WHY???”
In a later tweet they wrote: “Canals Team cleared dumped bread from our lake this morning, a good wash down of the tools and van and us to get rid of the smell was carried out, a challenging morning but all clear now."