Two water main breaks late yesterday afternoon in Monessen caused the city to lose much of its drinking water by 10 p.m. and city officials to call for emergency efforts to conserve.

Emergency officials said the two breaks happened by the Charleroi-Monessen Bridge on Route 906. They were unsure what caused the breaks. Nearly 9,000 people were affected.

Officials instituted a citywide water conservation effort. The city said the emergency could last 48 to 72 hours. Most citizens lost drinking water around 10 p.m.

The Monessen Emergency Management Agency advised residents in need of drinking water to go to City Hall, at Third and Donner avenues, or the Mon Valley Emergency Medical Services building at 1001 Donner Ave.