Floating pennywort was pulled from the River Lee on Sunday (July 3) in a bid to stop the non-native invasive weed choking the water.
The weed spreads rapidly feeding on nutrients in the polluted river and the clean-up was spearheaded by water charity Thames21.
The charity last week revealed the river is more polluted than parts of the River Ganges in India.
It has now launched the Love The Lee campaign to rejuvenate the river and appealed for volunteers to get involved with the clean-up.
Theo Thomas, of Thames21, said: “There’s nothing like this being done anywhere in the UK. This river is the most polluted and degenerated in the UK and we’re very keen that this stops and becomes a river that residents can be proud of.”
The next clean-up event is scheduled for August 6.
Anyone interested in taking part should contact Vicky D’souza on firstname.lastname@example.org