Bay City water worker Tom Stepanski prepares to go down into a water vault on the city's East Side in hopes of finding a broken water main. (Andrew Dodson | The Bay City Times)

BAY CITY, MI — Bay City crews were unable to find the source of a broken water main Sunday evening and will continue their search in the morning.

Working near the Ed Golson Boat Launch on Johnson Street at the railroad crossing in Bay City, a city crew drained a water vault, sent a worker down about 20 feet into the ground, turned off the main that stretches underneath the Saginaw River and waited.

About two minutes later, officials from the Bay City water plant radioed back that pressure increased 2 pounds per square inch — a positive sign in an effort to find a needle in a haystack — but then pressure dropped off again.

No luck.

"We'll regroup in the morning and find it then," said Bob Dion, the city's water distribution supervisor. "It's frustrating. Trust me, it's frustrating."

Since a main break was discovered at about 10:30 a.m. on Saturday, Aug. 9, about 5 million gallons of water has been lost every 12 hours, resulting in the city issuing a water-use emergency that stretches across Bay County. Residents are being asked to conserve water. Officials have said more water is coming into the water plant than going out.

"So if residents really conserve water for only basic needs, we can get through this," said Bay City Manager Rick Finn.

Related: Everything you need to know about Bay County's water emergency

Under the water-use emergency, residents are asked to avoid unnecessary water use, including laundry, watering lawns and washing cars. Residents are also being asked to cut down on water for basic life needs, such as personal hygiene.

All Bay County residents are impacted by the water emergency except residents in the city of Auburn, village of Linwood and Frankenlust Township, west of Interstate-75.

Bay City and Bay County businesses will also be notified by officials concerning their water use.

The search for the main break thus far has been extensive. Firefighters from neighboring townships have driven Bay County roads in the hopes of finding flowing water. A Michigan State Police helicopter was used to survey farm fields and Bay County Central Dispatch sent out an alert asking farmers to check their fields for any unusual water.

There are five mains that go under the Saginaw River, each of which take about 2 hours to check for a leak by having crews shut off valves on both ends.

"There's nothing except flowing water that can point us to the source of a break," Dion said. "That's what makes it difficult."

The city is also dealing with misinformed rumors popping up on social networks.

One rumor suggested the city found the break and was shutting off the water at 10 p.m. Sunday. That isn't true. Crews will be back at it beginning at 7 a.m. Monday, Dion said.

Tom Stepanski, a 23-year veteran of the Bay City water department, was the employee who went down into the water vault to turn off the valve on Johnson Street Sunday. After officials determined the main wasn't the source of the break, Stepanski wiped off sweat and old water from his arms and forehead.

"It was worth a try," he said. "We'll get it soon."