Sewage spills are adding to the headache of Irma clean-up throughout hurricane-battered Florida.
Local governments have reported more than 100 spills since Irma struck, some involving millions of gallons of wastewater.
The outages disable stations that pump wastewater to plants for treatment. About 6 million gallons of sewage were released from a plant on Virginia Key near Miami during a seven-hour power interruption overnight Sunday.
Officials are warning residents to avoid standing water that may be contaminated.
Federal and state teams will help assess damage to drinking water and sewage systems.
Many Florida cities have a long history of wastewater spills because of decaying infrastructure and a booming population concentrated in coastal.