Bay of Plenty Regional Council is assuring residents that the brown sludge that’s washed up on some beaches is nothing to worry about.

The brown sludge or foam is a natural occurrence of surf algae.

The sludge is not associated with the discharge of dairy farm effluent.

Residents of Ohope and Tirohanga Beach have noticed an occasional build up of the sludge along the shorelines, and council’s senior environmental scientist Stephen Park says it is a common non-toxic sea plant.

– Newstalk ZB