Lough Neagh Water Safety Update

The Northern Ireland Environment Agency (NIEA) were alerted on Friday 19 May 2023 to a report of the death of a dog that had been in the water at Lough Neagh.

NIEA carried out a number of tests over a few days to investigate if there was evidence of an algal bloom in the water. No visual evidence of an algal bloom, dead fish or any other signs of water pollution including sewage were detected at that time.

As a precautionary measure a water sample was taken for algal analyses. No blue green algae were found in the water sample analysed by NIEA.

Further samples were collected along the shore at Rea’s wood on 23 May 2023 and analysis has confirmed the presence of an algae called Microcystis sp. in small amounts washed up on the shore. Microcystis sp., is a blue green algae which can produce toxins that are highly poisonous and often fatal to pets.

In addition, a large amount of the toxic but fairly common plant Hemlock Water Dropwort (Oenanthe crocata) was observed growing in the wooded area along Rea’s Wood.

Hemlock water dropwort (poison parsnip) is perhaps the most poisonous indigenous plant in Britain and Ireland. This is a native plant, not an invasive species, and it grows mostly in wet meadows along river courses and adjacent to lakes. It is highly toxic to humans and domesticated animals if ingested - although the roots are more toxic than the above-ground parts.

Dog Owners should always be aware of the dangers posed by all poisonous plants and algae growing in the environment, but especially along riverbanks and in wet grassland or edges of lakes.

The Council has erected signage warning the public of the presence of blue-green algae and Hemlock Water Dropwort in the area and advising that dogs are kept on a lead at all times.