As of early afternoon Friday, a boil water notice from the Altoona Water Authority was in effect for customers in the area of Fourth Street between 25th and 26th avenues, due to a water main break that occurred there Tuesday, according to the authority’s website.

Authority workers have made repairs, including replacement of two broken valves on Thursday.

As of Friday afternoon, employees were collecting and testing water samples to ensure water being distributed in the area was safe to drink.

The boil water notice was to be in effect until test reports are favorable.

When the notice is lifted, the authority will update its website and notify affected customers directly through voice and/or text message, if the authority has their phone numbers on file.

The boil water notice applied to at least some customers on the 300 block of 26th Avenue, the 300 block of Wopsononock Avenue, the 300 block of 25th Avenue, the 2500 block of Third Street, the 400, 2500 and 2600 blocks of Fourth Street and the 2500 block of Fifth Street.

The main break caused a loss of positive water pressure, which may create conditions that can allow contaminants to enter the distribution system “through back-flow by back-pressure or back-siphonage,” according to the website.

Boil water notices recommend that customers bring water to a rolling boil for a minute before then cooking it prior to its being used for drinking, making ice, washing dishes, brushing teeth or food preparation.

Bottled water is an alternative.

More information is available from the authority at 814-949-2540.