Three Swampscott beaches are closed Friday due to elevated bacterial levels.

King’s, Fisherman’s, and Phillips beaches have been posted with no-swimming advisories for Friday. The town says signage will be removed Saturday afternoon if updated test results show safe conditions.

King’s Beach is currently closed on the Lynn side, including areas near Eastern Avenue, Kimball Road, and Pierce Road.

The Massachusetts Department of Public Health considers water safe when bacterial levels are at or below 104 colony-forming units per 100 milliliters (cfu/100 ml).

Exact water quality results for Friday were not available on the state’s website as of publication. The dashboard is updated hourly from 8 a.m. to 5 p.m. daily, including weekends, during beach season.

More than 1,100 public and semi-public beaches are monitored across Massachusetts. Samples are collected three feet from shore and one foot below the water’s surface.

“If a beach is closed, do not swim or enter the water at that location to avoid risk of illness,” the state’s division of environmental toxicology stated.

Bacterial contamination can result from various sources, including stormwater runoff, septic system failures, leaking sewer lines, wildlife and pet waste, and agricultural runoff.

The area experienced steady rainfall on Thursday, July 10.

Swimming in contaminated water can cause gastrointestinal, respiratory, or skin-related illnesses.