Men are filmed using a hose and closing rubbish bins, as the US orders the mission's closure.
The technique is "too often" used in situations that lead to death, says Houston boss Art Acevedo.
Brooke Williams, George Floyd's niece, said 'justice would be served' for him as long as she is breathing.
By Paul Rincon
Science editor, BBC News website
By Hazel Shearing
Flooding in Houston led to cars being submerged and people having to take refuge on their roofs.
By Simon Head
By Mark Mitchener