More on KentOnline
A group of environmentalists are campaigning to save marshes next to the QEII bridge.
Cotton Marshes, which lays behind the river path and the bridge, has been earmarked for industrial units.
Save Cotton Marshes are asking people to get in touch with councillors and Dartford MP Gareth Johnson to lobby them to halt the development.
According to the group, the marshes are home to a variety of wildlife including nightingales, reed buntings, sedge and Cetti's warblers, butterflies and bumble bees.
Rebecca Hayat, from the group, said: "They seem to be clearing the site before it's real wildlife potential can't be assessed.
"However, the area of mud and stones they've created will restore itself if the workmen leave now.
"Without little patches of wild like this one, Dartford will lose much of it's butterflies, bees and birdlife between the new housing and modern farming techniques."
To find out more about the campaign, click here.