On Tuesday, the drinking water system in Mississippi’s capital was on the verge of failing, cutting off access to safe running water for more than 150,000 people as officials struggled to deal with the “massively complicated task” of distributing bottled water and devising a plan to restore service.

For years, the water system in Jackson, the state’s largest city, has been crippled by aging and inadequate infrastructure, as well as a lack of resources to repair it. Residents have long had to deal with outages and frequent boil-water notices, including one that had been in effect for more than a month due to cloudiness found in water samples.

This week, officials announced that the city’s largest water treatment plant was failing. Water pressure in homes and businesses was low to non-existent. And officials warned that whatever did come out of the faucets was not safe to drink because it was most likely untreated water from the city’s reservoir.

“Until it’s fixed, it means we don’t have reliable running water at scale,” Mississippi Gov. Tate Reeves said during an emergency briefing Monday evening. “It means the city cannot produce enough water to fight fires, flush toilets consistently, and meet other critical needs.”

And it was unclear how long it would take to bring that back, he added.

Days of torrential rain have increased the risk of flooding in Jackson and engorged the Pearl River, which runs through the city, as well as the Ross R. Barnett Reservoir, a 33,000-acre lake northeast of the city. Though the rising water did not reach the feared levels, city officials said it rose high enough to disrupt water treatment operations.

State officials, on the other hand, were more pessimistic, saying the city’s water system appeared to be on the verge of failure even before the floods. “It was a near certainty that Jackson would cease producing running water sometime in the next several weeks or months if nothing materially improved,” Republican Reeves said on Monday.

The governor stated during the briefing that state officials were still attempting to assess the situation inside the water treatment facility. He stated that the plant’s two primary pumps had failed, leaving the plant reliant on backup pumps whose status was unknown. “It’s not even close to capacity,” Mr. Reeves said of the facility, “and we might find out tomorrow that it’s not even operating at all — we’ll find out.”

Officials from emergency management began organizing a massive response, including gathering thousands of bottles of water to distribute at the city’s fire stations. Mr. Reeves encouraged residents who could afford it to buy their own bottled water. “Leave these resources for those who truly require them,” he said of the emergency supplies.

The effects of the facility’s problems reverberated throughout Jackson, a city of 150,000 people, as well as Byram, a city of about 11,000 people southwest of Jackson that uses the same water system.

Jackson’s public schools adopted virtual learning, and a lack of water disrupted the operations of many businesses.

However, the situation is all too familiar for many Jackson residents, as the city’s water system has been plagued by repeated failures in recent years. In 2021, the system was crippled for weeks after a powerful winter storm dumped snow and ice on Mississippi, causing pipes and water mains to burst.

The water system is emblematic of the larger issues confronting Jackson, which is the seat of state government but has been drained of resources over decades. As white residents fled to the surrounding suburbs, they took much of their wealth and tax revenue with them. Following that, Jackson, which is now roughly 82 percent Black, has struggled with chronic issues such as crime and faulty infrastructure, and elected officials claim the Republican-controlled state Legislature has failed to invest in the city.

On Monday, some state lawmakers urged Mr. Reeves to call a special session of the Legislature to address Jackson’s water system. Those lawmakers noted the level of support that other communities had received from the state and said they believed Jackson deserved something similar.