The Adelaide City Council is about to start removing at least some of this green duckweed which has discoloured the Torrens Lake over the past few weeks.

Duckweed appears every now and again in the River Torrens / Karrawirra Pari.

Sometimes confused with green algae, duckweed actually provides some environmental benefits to water quality.

According to aquatic biologists:

Duckweed is an important source of food for fish and waterfowl. Duckweed provides a habitat for certain types of frogs and fish. It also maintains the habitat by providing enough shade to keep the growth of oxygen-robbing algae down.

It can be used as a human food, as it has a high protein content:

Nevertheless it's not seen as attractive and so the City Council is preparing to remove at least some of it

A City Council spokesperson has advised us that

"We are developing a plan to hopefully start removing some of the duckweed [this week].

"Whilst it’s doesn’t look great, up until now it hasn’t been a urgent priority to remove the duckweed because it’s a naturally occurring plant that has a number of positive environmental impacts and doesn’t pose any risk to people.

The duckweed has proved popular with some of the waterbirds on the River Torrens, including these coots and some cormorants. They might soon be disappointed to see it gone.