Crackdown on water-weed looming

Floating pennywort forms dense mattresses on rivers

The Environment Agency has won funding to step up a campaign to eradicate a North American water-weed threatening river habitats in Cambridgeshire.

Floating Pennywort was first spotted in rivers three years ago and now blocks navigation and threatens wildlife.

The agency has spent £50,000 this year in a bid to eradicate the weed.

Terry Clough, from the agency, said floating pennywort was the public enemy number one invasive species and they now had government cash to kill it off.

The weed was a dangerous alien because it blocked rivers and depleted oxygen levels, threatening other animals and plants.

The water-weed, first detected on Cambridgeshire rivers in 2006, has the ability to grow by 20cm (8in) in a single day.

We have a number of invasive species along our rivers, such as mitten crab, signal crayfish and Japanese knotweed, but of all these I see floating pennywort as public enemy number one Terry Clough

It grows in dense mattresses that choke waterways, making it difficult for boats to navigate and increasing the risk of flooding by slowing down water flow.

It also poses a threat to fish and other aquatic life by starving the water of light, oxygen and nutrients.

The Environment Agency tackles the problem by using weed cutting boats with special lifting mechanisms as well as harvesters and herbicide.

This year the agency has cleared over 60km of waterways of the menace.

Mr Clough said: "We have a number of invasive species along our rivers, such as mitten crab, signal crayfish and Japanese knotweed, but of all these I see floating pennywort as public enemy number one.

"We successfully bid for some external funding from the Department of Environment, Food and Rural Affairs earlier in the year to help pay for removing floating pennywort."