Haverhill's Stour Brook turned white by limestone powder spillage
Anglian WaterA waterway turned milky-white due to a limestone powder spillage, investigators have found.
Anglian Water said the Stour Brook in Haverhill, Suffolk, became discoloured earlier this month after the spillage at a nearby industrial estate.
The Environment Agency (EA) said the spillage was cleared by the operator and the water returned to its natural colour within 24 hours.
It said there was no impact on wildlife and no further action would be taken.
The EA had notified Anglian Water after reports of the substance on 10 May.
It said investigations by the water company showed a slight increase in ammonia concentrations, which were traced to a surface water outfall near Coupals Close and Victory Row.
A blocked sewer was also found on Helions Bumpstead Road and cleared.
The EA said officers took water samples the following day that revealed the impact on the brook was "minor, localised and short-lived".
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