Environment Agency launches investigation as algae problem spreads

Harbours around Britain are being 'suffocated' by algae, according to the Government’s environment watchdog.

By Louise Gray, Environment CorrespondentPublished: 2:51PM BST 19 Aug 2009

The green seaweed saps oxygen from water - meaning other marine life cannot survive - and spreads, taking over hundreds of acres of mudflats and estuaries.
The Environment Agency (EA) is so concerned about the problem that it is mapping out how far the algae has spread using aerial images.

Algae blooms happen when nutrients from sewage works or fertilisers from farms leak into the sea from rivers. A period of sunshine then allows the plant to grow.
This year has been particularly bad after a spell of rain followed by warm weather.
The areas affected are Chichester and Pagham harbours in Sussex, Portsmouth and Langstone harbours in Hampshire, Newtown and Bembridge harbours and the Medina estuary on the on the Isle of Wight, the Hamble estuary in Hampshire and Poole Harbour and Holes Bay in Dorset. An area around Lindisfarne in Northumberland, Seal Sands around Teeside, the Ythan Estuary in Aberdeenshire, Belfast Lock and the Montrose Basin in Angus have also been affected.
In France an area around Brittany was recently struck by toxic algae after a large amount started to decompose.
David Lowthion, marine team leader at the EA, said the problem is set to get worse with climate change because of warmer wetter summers. Also as populations grow and farmers use more chemicals.
“Green sea weed is growing in harbours around the UK in fairly large amounts and in some areas causing ecological issues,” he said.
He said the seaweed can group up to several inches deep, starving invertebrates like worms and therefore affecting birdlife and other animals.
“It suffocates the animals in the mud underneath and changes the whole balance of the ecosystem,” he said.
Every summer the Environment Agency carries out an aerial survey to find out how widespread the problem is and will then work with farmers and local authorities to “starve the algae” by reducing the run off from fields and stopping leaks from sewage works.
In a separate operation the agency has teamed up with the Met Office to provide “algae” forecasts for bathing areas in the UK.
The satellite images use high tech cameras to detect a slight discolouration in the water that can cause algae.
At the moment the technology is being piloted in the South West but will be used to provide “algae forecasts” for popular bathing areas around the country by 2015 when new European laws will make it obligatory.