Thousands of people were evacuated from their homes in Delhi on Thursday after the authorities warned of widespread flooding following days of torrential rains that have battered large swaths of northern India.

The level of the Yamuna River, which flows through the Indian capital and is a tributary of the Ganges, had breached the so-called danger mark by three meters (about 10 feet) on Thursday, according to the Central Water Commission. That forced the chief minister of the capital region, Arvind Kejriwal, to shut schools and convert them into disaster relief camps.

Many migrant workers, who live on the banks of the river, were camping on the roads alongside it as their makeshift homes were swallowed by the water. Others had to evacuate to try to reach higher ground.

Many others were looking for shelter as water enveloped sections of residential areas and historical sites like the Red Fort.

So far this monsoon season, officials said, landslides and flash floods have claimed at least 91 lives in six north Indian states near Delhi, and disrupted millions of others. Indian Army personnel were seen rescuing villagers after the Sutlej River flooded in the state of Punjab, on Wednesday.

Entire streets were flooded in the capital.

In the city of Amritsar in Punjab, people waited for trains inside a station after rail services were disrupted by heavy rains on Tuesday.

Three water treatment plants were shuttered in the capital because they were flooded, and many neighborhoods in what is one of the biggest metropolitan regions in the country could face shortages of drinking water.

“Twenty-five percent of the water supply will be affected by this,” Mr. Kejriwal said about the closure of water treatment plants. “People will face difficulties, and they have to bear it. I appeal to the people not to come out of their homes and do maximum work from home.”

Residential areas like the upscale Civil Lines, where Mr. Kejriwal lives, were also flooded. A boy walked on a wall of his flooded house in Delhi, on Wednesday.

Residents sought dry ground.

A woman collected her belongings before relocating from a low lying area near the Yamuna River in northeast Delhi.

And rescue crews worked to evacuate people from the high waters.

So far this season, the hardest-hit area has been the Himalayan state of Himachal Pradesh, where at least 45 people have died since Saturday. The rains have destroyed infrastructure worth millions of dollars there, and in the state of Haryana, thousands of acres of agricultural crops. Tens of thousands of people remain stranded in the state of Uttarakhand, where roads leading to four important Hindu pilgrim sites have been blocked for the last few days.

India has often experienced extreme weather patterns, including record heat waves and heavy floods in monsoon season. Every year, the monsoon brings 80 percent of South Asia’s annual rainfall in a season that starts in June and ends in August. But in recent years, it has become erratic and more extreme, delivering death and destruction through floods and landslides.