The risk of major flooding looms increasingly large along the Huaihe River, part of the dividing line between northern and southern China. The rain-swollen river has risen above alert-triggering levels, with more torrential rain forecast for the river's basin.
The rising threat of the Huaihe comes as flooding continues along the Yangtze River.
Due to incessant downpours, the water level of the Huaihe at the Wangjiaba hydrological station reached 27.5 meters, its warning level, late on Friday, marking the river's first flooding this year.
However, the water level further increased to 29.66 meters at 6:36 am on Monday-0.36 meter above the maximum design level for dikes in the section, according to the Huaihe River Commission.
"The water is expected to keep swelling," the commission said in a news release on Monday.
The Huaihe River, one of the country's seven major waterways, drops 178 meters over 360 kilometers in its upper reaches. In its middle reach of 490 km, mostly in Anhui province, however, the drop is just 16 meters, making it difficult for floodwaters to recede in the province.
The Huaihe also passes through Henan, Jiangsu and Shandong provinces.
The commission issued a red alert for flooding, the highest in a four-tier, color-coded warning system, on Monday morning while upgrading the emergency response to Level I, its highest, amid a "grim flood control situation".
At 8:30 am on Monday, the Wangjiaba Dam opened all of its 13 sluice gates to discharge floodwaters to the Mengwa Flood Diversion Area, in an effort to relieve pressure on downstream areas.
The diversion area, a 180-square-kilometer basin, can hold nearly 750 million cubic meters of water. Located in Fuyang, a city in Anhui, the area is home to more than 190,000 people. However, most of its residents are migrant workers in other regions.
"Over 2,000 people in the area were evacuated on Sunday night to safe places," said Lu Haitao, an official on Huaihe River management at the Anhui Department of Water Resources.
Some of those who live in places high enough to avoid being affected have gone to stay in other places with friends or relatives. The government will take steps to ensure the supply of daily necessities to people who stay at home, he added.
The flood control situation along the river may become even more acute due to additional downpours.
From Monday to Wednesday, heavy rainfall is expected to hit the drainage basin of the river, raising the risk of flooding at its trunk stream. "Some medium-sized and small rivers may suffer major floods," the Ministry of Emergency Management said.
But it added that rainfall in southern parts of the country that has continued for more than 40 days will tend to abate as the rain band moves northward.
The Huaihe River and the Qinling Mountains to the west are regarded as the dividing line between northern and southern China.
Along the Yangtze River, meanwhile, the flood threat continued on Monday. Jiangsu province raised its flood alert to red for Taihu Lake, Shijiu Lake and the Nanjing and Zhenjiang sections of the Yangtze on Monday.
The water level at the Nanjing hydrological station reached a historic high of 10.32 meters as of 2 pm Monday, according to the Jiangsu Water Resources Bureau. The previous record high was 10.22 meters in August 1954. The water level will remain high for about a week, according to the bureau.
Nanjing's Qixia district had evacuated 306 elderly or disabled people from Baguazhou Island, the third-largest island in the Yangtze, to eight nursing homes by Sunday. Medical workers from 11 hospitals and medical centers accompanied the evacuees to ensure their health during the evacuation and at the homes.
Zhang Guilan, a villager in her 80s, said she was satisfied with the food and living conditions at her nursing home.
"I had a chicken drumstick, cabbage and a bowl of seaweed soup for dinner," said Zhang. "The room I'm living in has a TV, clean bedclothes and bathtub safety rails. The food here is even better than what I had at home."
Zhang said she has confidence in Nanjing's flood defenses and believes they will protect the city, since she had witnessed how they were built.
Since 2016, Nanjing has invested more than 8 billion yuan ($1.14 billion) to reinforce its flood defenses, including the 200-km dike on the Yangtze's main stream.