More than 30 Auckland beaches are unswimmable due to a high risk of illness, according to the Safeswin website.
While some North Shore beaches are safe, many in the west, south and centre of the city aren't.
Beaches at a "very high risk" of illness include St Mary's Bay, Home Bay, Herne Bay, Te Tinana and Point England.
Beaches at "high risk" include Coxs Bay, Point Chevalier, Meola Creek, Judges Bay, Kenndal Bay, Farm Cove, Beach Haven, Soldiers Bay, Blockhouse Bay, Titirangi Beach and several others.
Safe beaches include north shore beaches from Devonport to Milford. Muriwai, Piha and Bethells Beach are also safe but Te Atatu isn't. For a full list of beaches click here.
It comes after heavy rain battered the city earlier in the week. A heavy rain watch was issued on Sunday for eastern Auckland between 3pm on Tuesday to 3am on Wednesday.
Auckland beaches have been plagued by water safety issues as the Council works to improve infrastructure and stop wastewater overflowing during bad weather.