Blue- inexperienced algae prompts bathing alerts at two NI seashores

Swimmers are disillusioned that they cannot get into the water as bathing alerts have come into impact on two north coast seashores.

It follows the affirmation of excessive ranges of blue-green algae.

It means swimming just isn’t permitted at Downhill and Portstewart seashores.

Increased ranges of algae have been detected at Castlerock seashore however no bathing discover is in place but.

Nicole Morelli is a part of the Menopausal Mermaids open water swimming group.

She and her mates are disillusioned to not have the ability to get into the water.

“We had such a great day yesterday, and we were really looking forward to getting back in.

“But it is higher to be protected.”

No other beaches are affected at this time.

In a statement, the Department of Agriculture, Environment and Rural Affairs said the algae had been observed on part of Magilligan, Downhill and Portstewart strands on Monday 22nd September 2025 during regular scheduled monitoring.

It said monitoring would continue and advice would be provided to bathing water operators when required.

The National Trust, which manages Portstewart Strand, said algae had been detected “at a red alert level” and it urged all guests to not swim, keep away from any scum or mats on the shore and to maintain pets away from the water.

Blue-green algae has been present in Lough Neagh all summer.

Recent weather conditions have led to portions of the algal mats travelling along the Lower Bann River to the North Coast.

In August, the first algae-related bathing ban on the coast was put into place at Benone.

It was lifted a few days later.

A statement from Causeway Coast and Glens council said: “Council has been made conscious that blue-green algae could also be current in waters at Downhill Strand.

“Currently beach users are asked to be vigilant to the possible presence of blue green algae.”

The council suggested seashore customers who suspect the presence of blue inexperienced algae to keep away from enjoying “with scum or mats on the shore”, keep away from letting “animals drink water, eat algae or swim”, and keep away from swimming, fishing, wading, boating, and kayaking.

“Pet owners should ensure that their animals do not have access to this water, dogs should be kept on a lead and away from the tide line,” the assertion added.

“At this stage council would urge vigilance at Castlerock beach.”