Water Conservation Advisory for Garrard Co. & Crab Orchard
Those affected include the entire City of Lancaster, customers of Garrard County Water Association and customers of Crab Orchard Water.
Officials said the water main is currently being fixed, but before the valves could be closed, the water supply had dropped to a "crisis" level.
They believe the break may have been caused by the weather.
After the line is repaired, customers will need to boil their water for three minutes until further notice.