Environmental protection officers are investigating claims of water pollution in the St Helier Marina.
The Government has confirmed the probe under the Water Pollution law.
It’s amid claims from environment campaign group Save Our Shoreline that tidal water which filled a construction site on the Waterfront could have become contaminated and drained back out to sea.
The Jersey Development Company has said water samples are regularly monitored.
We’re told nothing more will be said by those investigating until their work is complete.

Channel Islander abandons Bordeaux as the flames 'arrive at the city's gates'
Man in hospital after serious assault at Havre Des Pas festival
Nowacki wins Jersey’s first Commonwealth Games medal in 36 years
No increase in domestic abuse reports in Jersey during World Cup
Commonwealth Games: Nowacki into 100m breaststroke final
Thousands expected at Havre Des Pas Festival this weekend
Channel Islands face 'physical' Poland test
Price of heating oil and other fuel increase by more than half in a year