WATERTOWN — Refilling the second, larger reservoir with water began early Saturday afternoon, but the boil water advisory continues in the city.

The city has been dealing with a massive water break that occurred Wednesday night that caused most of the city to lose running water the next day.

The boil advisory will probably remain in effect until midweek, City Manager Kenneth A. Mix said late Saturday afternoon.

“The most important thing is that people know the boil water advisory is still in effect,” he said.

He was at the city’s water treatment plant on Huntington Street on Saturday afternoon checking on the situation.

The state Department of Health has begun testing whether bacteria limits are below state standards, he said.

The DOH is testing 20 sites around the city once every 24 hours until it’s determined that the water meets those standards.

The Declaration of Emergency also remains in effect.

The boil water advisory also continues for the town of Watertown, Pamelia, Champion and another communities to which water is supplied by the Development Authority of New York.

The city began replenishing the 5 million gallon reservoir at Thompson Park after the 3 million gallon one was filled earlier Saturday.

After that one was filled, the city’s Fire Department decided it could get back to normal operations. Fire hydrants can once again be back in use.

Fire Chief Matthew Timerman said the city had enough water back in its system and the situation improved enough that his department has access to hydrants.

Both the city and town fire departments are back to normal operations, Timerman said.

“Residents can be assured that water levels to fires in their communities are approaching normal levels,” he said.

With that development, the city and fire departments and Jefferson County Emergency Management determined that a water tanker task force that had been mobilized during the city’s water emergency could be disbanded. Fire departments across the North Country had been lending fire engines during the water emergency.

The city also will no longer have the need for a large hose that the state provided that could pump 4,000 gallons a minute in case there was a fire in the city.

The city needed the equipment after the it ran out of water due to a massive water main break on Wednesday night in front of the city’s water treatment plant at Eastern Boulevard and Huntington streets.

The city’s two reservoirs in Thompson Park were without water because of the water main break.

The city and town fire departments would like to thank city public works and water department employees, county emergency management and state officials for their support during the water crisis. Fort Drum, Brookfield Renewable and Knowlton Technologies also were involved in the efforts.

Twenty fire departments in the region provided fire engines on standby before the hydrants were again operational.

The main that broke Wednesday was installed in 1939. The water main break leads out of the water treatment plant to the two reservoirs.

The 16-inch pipe was repaired late Thursday afternoon and a deep hole at the site has been refilled.