Far North warned to avoid Lake Rotopotaka due to toxic algal bloom

Councils warn to avoid swimming and contact with the lake waters until health warnings are removed. Photo / File

Far North residents and visitors are warned to stay clear of Lake Rotopotaka, also known as the Coca Cola Lake, on the Karikari Peninsula as toxic algal blooms are covering the lake.

Sampling undertaken by the Northland Regional Council has found Lake Rotopotaka at Cape Karikari is not suitable for swimming at the moment, and humans and animals – in particular dogs – should avoid contact with the lake waters until health warnings are removed.

The Far North District Council will place warning signs at Lake Rotopotaka while the algal bloom causes health risks.

Exposure to cyanobacteria may cause symptoms such as skin rashes, nausea, tummy upset, and tingling or numbness around the mouth or fingertips.

Ken Lewis, Far North District Council spokesperson, said algal blooms occurred more frequently during hotter summer temperatures, so this is not directly linked to the current drought.

Lake Rotopotaka is deemed unsafe to swim due to algae bloom. Photo / Adam Pearse

"This does not occur every year, but it is frequent enough for there to be contingency planning around algal blooms for this and other lakes in the region," he said.

Due to a high bacterial count, swimming in Kerikeri River is also unsuitable at the moment.

Kaipara District had a short-lived algal bloom in early December; however, all freshwater spots are currently suitable for swimming.

In Whangārei District, the regional council warns people to avoid Taurikura Bay due to a high bacterial count, and, while the water quality in the Hātea River usually is suitable for swimming, young children and older people may be at increased risk of infection.

Swimming in the lake might cause skin rashes, nausea, tummy upset, and tingling or numbness around the mouth or fingers tips. Photo / File

If you experience any adverse health symptoms after contact with contaminated water, advise the on-call Health Protection Officer at Northland District Health Board on 09 430 4100 and visit a doctor immediately.

Boiling water does not remove toxins, so drinking should be avoided at all times.

Residents should check the regional council Can I swim here? webpage nrc.govt.nz/living-in-northland/at-the-beach/swimming-water-quality/ or lawa.org.nz/explore-data/swimming/.