Warning over Stenness Loch algal bloom

Following reports of a dog becoming ill after swimming in the Stenness Loch, the OIC’s environmental health team is advising that the water may be affected by a bloom of blue-green algae.

As a precautionary measure, notices have been posted next to the loch, warning that contact with algal scum or denser “mats” of algal material should be avoided. Blue-green algae growth is a natural occurrence. Warmer weather and higher water temperatures can lead to multiplication of the algae in fresh water lochs, waterways and brackish sea lochs.

It can, in some cases, cause an upset stomach or skin problems for people and animals.

Signs of higher levels of the algae include a blue-green, greenish brown or dark brown colour in the water and possibly a bloom or scum, particularly at the water’s edge.

OIC environmental health manager David Brown said: “People visiting lochs – and Stenness Loch in particular – are asked to be vigilant and check whether there are signs of blue-green algae growth in the water or around the shoreline.

“Where there is evidence of this, it would be sensible to avoid swimming or other water-based activities – and to make sure that pets don’t drink or enter the water.”

For further advice, contact the environmental health team on 873535 ext. 2801 or env.health@orkney.gov.uk