Environment Agency don't expect blue-green algae to spread to other beaches after North Coast finds

The Environment Agency doesn't expect the toxic blue-green algae which has closed a number of beaches to continue to spread.

Last week the bacteria was found at beaches in Castlerock and Portstewart.

A suspected discovery of the algae was made at Downhill on Sunday, while as a precaution Benone beach has also been closed to swimmers due to the coastal tides.

“We don’t expect it to move much further,” Dr Gareth Greer told UTV.

“The Benone-Downhill area is probably the last major designated bathing area along that side.

“Obviously the further this moves away from the River Bann there will be more dilution and further spread of the algae so the risk should reduce the further away from the original source.”

The Department of Agriculture, Environment and Rural Affairs explained: “Blue-green algae is not actually an algae but rather a type of bacteria called cyanobacteria.

"Cyanobacteria naturally inhabit our freshwater, coastal and marine waters and, like plants, require sunlight, nutrients and carbon dioxide to grow and reproduce.

“Cyanobacteria can increase greatly in numbers and form visible ‘algal blooms’ which can lead to poor water quality and potential toxicity. Suitable conditions for ‘blooms’ to occur include abundant sunlight, still or slow-flowing water and sufficient levels of nutrients (nitrogen and phosphorus).”

It’s thought the algae found on the beaches on the north coast originated in Lough Neah.

“Over the last six to eight weeks we had a major algae bloom in Lough Neah and all that water in Lough Neah flows down the River Bann and enters the sea at the north coast,” explained Dr Greer.

Here we answer some questions on the algae:

What has been found on the beaches?

Blue-green algae. It can cause illness in humans and animals have been found across Northern Ireland during the warm weather we have had.

Why has this algae appeared?

The National Trust says the issue a symptom of a wider problem of poor water quality and its appearance a sign of how there is a need to look after waterways better.

The potentially blooms often increase in the summer months, due to warm waters which allow the bacteria to multiple.

Normally the blooms are in freshwater lakers, rivers and streams.

The algae can be influenced by increased nutrients in the water which often comes from agricultural or sewage run off into the river.

Despite its usual occurrence in freshwater, the bacteria has started to crop up in coastal and off-shore areas around the UK and Ireland.

Where has the algae been found and where had it come from?

The blue-green algae found in the water in Castlerock and Portstewart is a freshwater species and is likely to have come from the River Bann.

What to do if you have come into contact with the algae.

The Public Health Agency advises anyone who has come into contact with wate to shower with fresh water immediately.

The PHA says if you have come into contact or drunk affected water and feel unwell you should obtain medical attention.

Symptoms generally begin within hours after exposure.

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