Blue-Green Algae blooms

It is the season for blue green algae appearing on our canals and reservoirs. In some circumstances BGA can produce toxic substances that can pose a hazard to humans, pets and livestock.

Please report any sightings via the Bloomin’ Algae app which will be automatically shared with the Scottish Environment Protection Agency.

Situation updates

Update 29th November 2022

The Scottish Environment Protection Agency (SEPA) has confirmed the presence of blue-green algae on the Birkenburn Reservoir, Kilsyth. Warning signage is being posted at access points to the reservoir.

Both NHS Lanarkshire and North Lanarkshire Environmental Health Department have been notified.

Update 24th November 2022

Following a notification from SEPA of Blue Green Algae (BGA) in Black Loch, Scottish Canals has updated the signage warning the public of a bloom in the loch.

The local fishery has also been informed of the BGA bloom.

Update 12th August 2022

A recent sample taken at Lock 17 on the Forth & Clyde Canal has confirmed the presence of blue-green algae. Warning notices have been posted at access points to Lock 17, warning that contact with the bloom should be avoided.

SEPA has been notified of the blue-green bloom, as have Forth Valley NHS and Falkirk Council Environmental Health Department.

Update 29th July 2022

A recent sample taken at Townhead Reservoir/Banton Loch has confirmed the presence of blue-green algae. Warning notices have been posted at access points to the waterbody, warning that contact with the algal bloom should be avoided.

SEPA has been notified of the blue-green algal bloom as have NHS Lanarkshire and North Lanarkshire Environmental Health Department.

Update 26th May 2022

Following a notification from SEPA of Blue Green Algae (BGA) in Black Loch, Scottish Canals has erected signage warning the public of a bloom in the loch.

The local fishery has been informed of the BGA bloom as have Forth Valley NHS and the Environmental Health Department of Falkirk Council.

Update 22nd October at 16:30pm

The BGA levels at the Black Loch were analysed by SEPA on 22 October 2021. The BGA count exceeded the trigger levels for the erection of warning signage. The warning signage on site will remain in place until further notice.

Update 22nd September at 11:00am

Following a notification from SEPA of Blue Green Algae (BGA) in Black Loch, Scottish Canals has erected signage warning the public of a bloom in the loch.

The local fishery has also been informed of the BGA bloom.

Update 24th August at 3:00pm

A BGA bloom has been identified at Hillend Reservoir, and a sighting has also been recorded at Loch Lochy by Laggan Locks.

Warning notices have been posted next to the waterbody, warning that contact with the algal scum or mat material should be avoided.

Update 23rd August at 11:30am

SEPA have informed Scottish Canals that there is a significant bloom blue-green algal at Townhead Reservoir (Banton Loch) in Kilsyth.

Warning notices have been posted next to the waterbody, warning that contact with the algal scum or mat material should be avoided.

Update 19th August at 3:30pm

Recent samples taken at the Forth & Clyde Canal between Bonnybridge and the Falkirk Wheel have confirmed the presence of blue-green algae. Warning notices have been posted next to the waterbody, warning that contact with the algal scum or mat material should be avoided.

Adjoining landowners and fishing interests have been advised of the situation as have the Environmental Health Department of Falkirk Council, SEPA and Forth Valley NHS.

At this stage there is no adverse effect on water supplies.

Notes to editors

About Blue-Green Algae

• Blue-green algae (cyanobacteria) exist in fresh waters in Great Britain and throughout the world; they are noticed when their concentrations increase to form “blooms” and when they form scums – looking like blue-green paint – or when they collect on the shore line as scums or mats.
• Some blue-green algae may give rise to adverse medical effects – but not always. Effects on people coming into contact with toxic scums include skin rashes, eye irritations, vomiting and diarrhoea, fever and pains in muscles and joints. Toxic algae have caused deaths of livestock and dogs, waterbirds and fish. The treatment of water supplies removes blue-green algae and additional treatment may be applied to destroy or remove toxins should they arise. The actions currently taken are precautionary.
• The behaviour of algae is erratic.
• The level of its toxicity can fluctuate; it can appear one day, be dispersed by the wind and mixing and re-accumulate at any time.