Water Recommendations After A Period of Non-water Usage
American Water Works Association Recommendations for Homes and Businesses After an Extended Period of Non-Water Usage
When homes and businesses reopen after an extended period of non-water usage (weeks or months), a thorough flushing process is appropriate.
Flushing instructions provided to occupants will vary depending on the type of structure. However, key elements of existing protocols include:
Organize flushing to maximize the flow of water (e.g., opening all outlets simultaneously to flush the service line and then flushing outlets individually starting near where the water enters the structure).
Run enough water through all outlets (e.g., hose bibs, faucets, shower heads, toilets, etc.), removing aerators when possible. Typical duration in existing protocols ranges from 10 to 30 minutes for each outlet (duration varies based on outlet velocity).
Flush the cold water lines first and then the hot water lines. Note: The hot water tank can be drained directly. It can require roughly 45 minutes to fully flush a typical 40-gallon hot water tank.
Replace all point-of-use filters, including the filter in refrigerators.