UPDATE: The boil-water advisory for parts of Maplewood and St. Paul was lifted Tuesday morning after tests show the water was not contaminated during a pressure loss at a Maplewood tank this past weekend.

Maplewood and St. Paul have issued a boil-water advisory for parts of those cities as a precaution after a water tank lost pressure.

The advisory was issued at 8:40 p.m. Sunday after a loss of pressure at the St. Paul Regional Water Service's Ferndale tank in Maplewood. When pressure is lost and water sits in a tank, there is a chance bacteria could enter the system, said Racquel Vaske, assistant general manager.

The advisory was issued as a precaution.

"There is no evidence that contamination has entered the distribution system at this time," the advisory stated.

On Monday, officials said pressure had been restored at the tank, but they had conducted tests to make sure the water was safe to drink and were awaiting results before giving an all-clear.

Patrick Shea, general manager of the St. Paul water service, said officials expect to see test results at 6 a.m. Tuesday.

Residents in the affected areas are being asked to boil water for three minutes before using it for cooking, drinking, brushing teeth and other tasks until the advisory has been lifted.

The affected areas include:

• Holloway Avenue E., between 7th Avenue E. and Division St./Holloway Avenue E.

• Geneva Avenue N. between Conway Avenue E. and Holloway Avenue E./Division Street.

• Conway Avenue E. between Carlton Street N. and Geneva Avenue N. and Avenue R.

• Ruth Street N. between 7th and Larpenteur avenues E.

• Winthrop Street N. between Larpenteur Avenue E. and Hoyt Avenue E.

• Idaho Avenue E. between Furness Parkway and Winthrop Street N.

• McKnight Road N. between Ivy Avenue E. and Margaret Street.

"We are dedicated to providing safe water for our customers and are taking this step out of an abundance of caution," Vaske said. "Employees have resolved pressure issues and are flushing and sampling to ensure we can confidently lift this advisory as soon as possible."

For a map of the affected area, go to the St. Paul Regional Water Services website.

Staff writer James Walsh contributed to this report.