About 350 households in Northern Cape Girardeau are under a precautionary boil-water advisory that is expected to continue through Thursday afternoon. The advisory, issued late Tuesday afternoon, impacts homes in the West Cape Rock/Snake Hill/Tanglewood/Cape Hills area and resulted from a water main break caused by construction activity. Although city officials said Tuesday there was no known contamination of the water supply, residents in the affected area are advised not to consume tap water until approximately 5 p.m. Thursday unless otherwise notified. Because of the large number of affected homes, work crews are unable to do door-to-door notifications. However, a link to a complete list of impacted addresses may be found online on the city’s home page, www.cityofcapegirardeau.org.