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Mary O'Hagan

Mary O'Hagan

Environmental activist from Derry, co-founder of the Save Our Shores / Save Lough Neagh campaign fighting the blue-green algae crisis at Lough Neagh, Northern Ireland.

Sep 18, 2026

speaker_0HOST
15:35
They're not obliged to tell you what's going on? No, they're
15:37
not.
15:38
Lough Neagh is green because there's too much phosphorus in it.
15:41
And that's the simple, very simple manner of it.
15:44
So phosphorus gets into the lake from various sources.
15:48
Agri-runoff, pollution from agricultural runoff.
15:52
um pollution from ni water so untreated sewage p and p going in from ni water um are the two main sources we would have of course a lot of septic tanks around the lock that contributes uh so faulty septic tanks if they're not operating properly then they're leaking into the groundwater and that's coming in we have an invasive species of zebra mussel in the loch and what the zebra mussel does is they make the loch water very very clear and that was one of the things that we noticed as a swimming group is that the loch suddenly it looked we were like oh it's so clean that's lovely look how far down you can see you can see the bottom and really what was happening was the zebra mussel was you know From where I usually swim at was in Ballyronan, and when I started swimming in Ballyronan, sandy bottomed, nose ever muscles, you walked out on your bare feet, it's fine.

17 MINS LATER

speaker_0HOST
33:29
So what's the solution going to

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