Water pollution

What is blue-green algae?

Blue-green algae are tiny organisms which occur naturally in lochs, ponds and reservoirs. They commonly occur during periods of prolonged hot weather but sometimes occur at other times of the year. Waters which have been polluted by agricultural, domestic or industrial discharges are prone to developing blue-green algae. 

In still waters the algae can multiply to such an extent that they discolour the water which then appears green, blue-green, greenish brown or dark brown. Sometimes a scum or slick may form on the surface. This can appear in different places at different times but is most commonly found at the water's edge or shoreline. Some, but not all the blue-green algae produce toxins and release these into the water. It is not possible to tell which algae do or do not produce toxins simply by their appearance. Laboratory analysis is needed for this and therefor it is advisable to regard all algal scum as toxic.

How does blue-green algae effects humans?

Swimmers and water sport participants who have either swum through algal scum or swallowed it have suffered from skin rashes, eye irritation, vomiting, diarrhoea and pains in muscles and joints. Illnesses can be severe, particularly where affected water has been swallowed.

How does blue-green algae effects animals?

The toxins of blue-green algae can cause serious illness and deaths of animals which come into contact with algae, either through drinking contaminated water or swallowing quantities of scum, shoreline matter or crust. Dogs may also ingest toxins by licking their coats after being in contact with blue-green algae. Illness may occur quickly and can be after very little contact has occurred.

What to do if you encounter blue-green algae?

Avoid all contact with the affected waters and ensure that children and pets are kept away. Farmers should ensure that their animals do not have access to contaminated water. This may require fencing around suspect waters. If you believe your pet may have been exposed to blue-green algae contact your vet as soon as possible to get advice.

If you think you have come across blue green algae, we encourage the use of the Bloomin' Algae app to record blue-green algae location. The app also allows you to upload photographs, and will alert you to identified areas where blue-green algae has been confirmed. The UK Centre for Ecology & Hydrology has further information regarding blue-green algae reporting using the app.

If any member of the public finds areas of water they believe may be affected with blue-green algae, take a photo and report it on the Bloomin' Algae website or app.  If you find areas of water affected with blue-green algae and do not wish to use the Bloomin' Algae website or app please email envprot@eastlothian.gov.uk.

What are we doing?

We are involved in trying to manage the risks associated with blue-green algae. This can be difficult given the increased occurrence due to the warmer, wetter climate and that the algae can appear and disappear in a very short time period. When alerted to the presence of blue-green algae we will advise landowners and if required, erect signs around the affected areas.