The Broads Authority and Environment Agency need the public’s help in reporting invasive garden pond plants which are threatening to choke the Broads waterways.
In the last few months alone Floating Pennywort has overgrown 1000 sq m of the River Waveney at Diss as well as a smaller area in the River Bure at Coltishall.
Andrea Kelly, Broads Authority Conservation Officer, said: ‘Floating pennywort could cause a nightmare for waterway management in the Broads. It has the potential to grow at an incredibly fast rate of up to 25cm a day, completely covering ponds and ditches and smothering river margins and channels.
‘If it colonises in the Broads it would have the potential to out-compete native vegetation and seriously compromise navigation and flood control. Unless we act now it could cost us tens of thousands of pounds, diverting money from other essential maintenance jobs.’
Floating Pennywort, which originates from America, is taking over wetlands all round Britain. It is believed that people are dumping it from their garden ponds into wild waterways.
Chris Adams, ecological appraisal officer at the Environment Agency, said the weed could cause several problems. Dense stands of it can have a big impact on ecology by covering large areas of water, excluding light and causing oxygen depletion.
‘The weed grows so thickly it can look like solid ground. This could put people and animals in danger if they don’t realise there is deep water underneath.
‘There is also a flood risk involved when this weed is dense in a watercourse. In major floods it could wash off into flood plains dispersing into and blocking smaller water bodies making it even more difficult to remove.
‘We would be grateful if people could let us know as soon as they see any invasive weeds so that we can arrange to have it removed before the problem grows. Some of our staff will be using their annual environmental leave to help clear the weed. The Broads Authority is also supplying guidance and volunteer help.’
The Broads Authority, the Environment Agency and partners are starting a Non-Native Species Forum to co-ordinate public awareness, control and surveillance and it needs your help to report the arrival of all non-native plants.
You can either telephone the Broads Authority or log on to the Broads Authority web site http://www.broads-authority.gov.uk/managing/wildlife/invasive-species.html
