The city health department is investigating the water supply at an East Village housing complex where two residents tested positive for Legionnaires’ disease, a form of pneumonia, over the past year, officials said.

City health officials advised residents of the Haven Plaza apartment complex against taking showers — even cold ones — in a May 15 notice that was shared with Gothamist.

“If you do not have a bathtub, you may use a bucket of water or hose to bathe,” the notice said. It further advised residents that they can drink cold water from the tap and can wash their hands, as long as they let the water “flow slowly to avoid mist.”

Legionnaires’ disease can be contracted by inhaling water vapor that’s contaminated with Legionella bacteria. The bacteria can grow in buildings’ plumbing systems and water cooling towers.

Large clusters of Legionnaires’ disease in New York City — such as the deadly outbreak in Harlem last summer — are typically associated with water cooling towers, which can spread water vapor over a larger geographic area. But the city also logs cases each year that are not tied to these clusters.

When two or more people who live in a building complex with a shared water system get sick from Legionnaires' over a 12-month period, the city health department investigates.

As part of the city’s evaluation of Haven Plaza, health officials are working with building management to test the water system, Chantal Gomez, a city health department spokesperson, said Friday.

City health officials also held a meeting with residents of Haven Plaza on Tuesday about the situation, which was attended by 60 to 70 residents, according to the city health department.

“The risk of getting sick from a building’s water system is very low, especially for healthy people, but those who are in high-risk groups are recommended to limit exposure to water mist while this work is underway,” Gomez said.

According to the city health department, those who are most at risk of getting sick from Legionnaires’ are people over 50 who smoke or vape or have a chronic lung disease or a weakened immune system.