A small amount of E-Coli-like bacteria have shown up in tests on the Kuressaare water system. Residents are advised to boil tap water before drinking until more precise tests have been carried out.
Kuressaare Veevärk said on Thursday that results from Staadioni and Talve streets showed contamination, newspaper Saarte Hääl writes.
"It is not clear at this stage whether this is new pollution or the residual effect of old pollution," said Aivar Sõrm, a member of the board of the water company.
New test results will be available on Saturday.
Until then residents are advised to boil tap water before consumption.
In May, several people were hospitalized after sewage water contaminated drinking water.
Editor: Mirjam Mäekivi, Helen Wright