Black sea water probably rotting seaweed - States
Rotting seaweed was probably the cause of water turning black on a Guernsey beach last month, the States has said.
Pictures showed a discoloured stream emerging around Havelet sea wall.
Islanders raised concerns after the cloudy-looking water was first spotted in October.
Tobin Cook, director of environmental health and pollution regulation, said: "We believe this is most likely to be due to the natural rotting of seaweed beneath the surface of the sand."
However, he added it had not been possible to "provide a definite answer", adding: "Havelet sea water is regularly sampled throughout the year as part of our routine sea water monitoring programme and we will continue to review this situation."
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