Angling and other activities at Newsham Park lake has been suspended from today after blue-green algae was discovered there.
Tests by the Environment Agency have confirmed the presence of the algae.
The algae grow in certain weather conditions and can be hazardous to pets and wild animals. It produces toxins which on contact with the skin can be harmful to humans. Algae can also de-oxygenate water causing problems for fish.
As a precaution, therefore, angling, use of model boats and other activities, have been suspended until further notice. The suspension is likely to last for a number of weeks.
The Environment Agency will be carrying out further tests on the lake and the city council will be providing more information to park users as it becomes available.
Liverpool park lakes are currently being monitored on a daily basis.