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Series 19, Episode 2: The Last Lake – Presented by Anja Murray

Lough Carra in County Mayo is one of the finest examples of a marl lake found anywhere in the world, it’s a place of exceptional geology and natural beauty. For thousands of years, a limestone white bedrock and crystal clear waters gave the lake an almost tropical colouring. But over the last 20 years the lake has started to change, anglers noticed a drop in trout numbers and the lake started to lose it’s characteristic turquoise colour turning a murky green instead.

The cause? The flow of phosphorus and nitrates from agricultural land that surrounds the lake in this largely rural part of County Mayo.

What can be done to stem the pollution flowing into the lake and ultimately restore it to its former natural beauty, before it’s too late? In this episode Anja learns what makes Lough Carra so special, meeting with scientists and community members who have come together to protect the lake.