Floods have severely impacted large tracts of southern China since June due to heavy rains caused by the regional rainy season, primarily around the Yangtze basin and its tributaries, with rains expected to hit central and eastern China during July, described as the worst since at least 1998.
According to the Ministry of Emergency Management, by the end of June flooding had displaced 744,000 people across 26 provinces with 81 people missing or dead. In early July, the South China Morning Post reported that about 20 million residents had been affected and at least 121 people were dead or missing. As of 13 July, floods have affected 37.89 million people in 27 provinces, autonomous regions and municipalities, 141 people are dead or missing, and 28,000 houses have collapsed. The Ministry of Water Resources said that a total of 443 rivers nationwide have been flooded, with 33 of them swelling to the highest levels ever recorded. According to statistics from the National Cultural Heritage Administration (NCHA), 76 key national cultural relics and 187 provincial cultural heritage sites have suffered damage of varying degrees.
El Niño has resulted in the abnormal weather in many parts of China. Hu Xiao from the China Meteorological Administration (CMA) indicated that the rains were caused by increased vapors arising from the Indian and Pacific oceans.
In 1915, Dongting Lake was 5,000-square-kilometre (1,900 sq mi). In 2000, it was only 2,625-square-kilometre (1,014 sq mi). In the 1950s, Poyang Lake was 4,350-square-kilometre (1,680 sq mi). In 2000, it was only 3,750-square-kilometre (1,450 sq mi).Hubei was once known as "The Province of Thousands of Lakes" (千湖之省). In the late 1950s, there were 1,066 lakes in Hubei. By the early 1980s, only 309 were left. With the rapid increase of population in China, in order to increase grain production and housing area, a large number of lake beaches had been transformed into farmland and homestead. The serious shrinkage and disappearance of lakes in the middle and lower reaches of the Yangtze River is an important reason for the aggravation of flood disasters.
Multiple dams in the Yangtze river basin control floodwaters; the biggest and most important of these is the Three Gorges Dam with its catchment area of about 1,000,000-square-kilometre (390,000 sq mi). It was constructed not only for power generation but also for flood control. By the end of June, the dam had started to release floodwaters. While the CMA indicated flood discharge started on 29 June, satellite images suggest that floodgates were opened already five days earlier.Yichang, a city below the dam, experienced extensive flooding, raising questions about the effectiveness of the flood control by the dam. There were fears that Wuhan could be flooded. According to the company that manages the dam, the dam had been "effectively reducing the speed and extent of water level rises on the middle and lower reaches of the Yangtze". Critics, however, suggest that the dam is "not doing what it is designed for" and unable to deal with severe events.
On 27 June, a 3-hour heavy rainfall of 118-millimetre (4.6 in) was recorded in Hefei Economic and Technological Development Zone, of which 94-millimetre (3.7 in) was recorded during 1.5 h from 17:30 p.m. to 19:00 p.m., which was rare for many years. Some road sections and communities were submerged.
On 14 July, an emergency was issued by the Office of Anhui Provincial Flood Control and Drought Relief, which ordered all residents living in the central island of the Yangtze River or along the Yangtze River in Anqing, Chizhou, Tongling, Wuhu and Maanshan to evacuate.
On 18 July, the Huai River Commission of the Ministry of Water Resources raised the flood-control response from Level III to Level II.
At 8:32 a.m. on 20 July, the Government of Nan County opened sluice gates at Wangjia Dam (王家坝) on the Huai River because water there was building up to too high a level. The last flood discharge was 13 years ago.
At 10:24 a.m. on July 21, the water level at Zhongmiao Station (中庙站) of Chaohu reached 13.36-metre (43.8 ft), which is the once-in-a-century water level of Chaohu.
At 20:00 p.m. on 22 June, the "Qijiang Wucha Hydrological Station" (綦江五岔水文站) in Jiasi Town [zh] recorded a water level of 205.85 metres (675.4 ft), which was 5.34 metres (17.5 ft) higher than the guaranteed water level (200.51 metres (657.8 ft)). The Qijiang Wucha Hydrological Station reached 205.85 metres (675.4 ft), topping the previous record of 205.55 metres (674.4 ft) in 1998 China floods. On 22 June, parts of Qijiang District's Wenlong Subdistrict [zh] were submerged, with some roads underwater. 13,874 residents in Qijiang District along the Qi River were ordered to evacuate on 22 June.
On 9th July, a rainstorm occurred in Nanping, causing floods, landslides and other disasters, many roads were destroyed and crops were flooded.Wuyishan City had serious waterlogging, and the local government issued a rainstorm red warning signal, and Wuyishan Scenic Spot had been closed.
At 11:00 a.m. on 8 June, roads and farmland in Lianxin Village of Linjiang Town [zh] in Heyuan were engulfed by floods. The Yonghan Levee (永汉堤) on the Dong River collapsed, releasing an 3-metre (9.8 ft) to 5-metre (16 ft) wall of water. Flood surrounded Hekou Village of Yonghan Town [zh] in Longmen County, making it an island. Roads and highways were severely damaged or destroyed in Longmen County.
From 07:00 a.m. on 11 June to 07:00 a.m. on 12 June, a torrential rain of 264.6 millimetres (10.42 in) fell in Bifeng Town [zh] of Zhen'an County, with the maximum hourly rainfall of 163.3 millimetres (6.43 in), breaking the historical record of Guizhou in one hour. It is also China's largest one hour rainfall, after Guangzhou of 168 millimetres (6.6 in) on May 22. Throughout the county, 8 people were killed and 5 were missing.
At 7:00 a.m. on 14 June, a total of 438,000 people in 51 counties of 8 cities in Guizhou were affected, 10 people died, 14 people were missing, 21,000 people were forced to evacuate; nearly 100 houses collapsed and more than 8,000 houses were badly damaged; 175,000 hectares (1,750 km2) of crops were affected, including 28,000 hectares (280 km2) will have no harvest; and the direct economic loss was 880 million yuan.
From 23 to 24 June, the torrential rainfall hit Rongjiang County, resulting in a direct economic loss of 92.1025 million yuan due to rural roads in the county sustained major damage.
On 11 July, Rao River rose to an all-time high of 22.65-metre (74.3 ft), crossing the danger mark and surpassing the previous record of 22.43-metre (73.6 ft) set in 1998. Parks, homes, and businesses in Poyang County were overtaken by the Rao River, leaving parts of the county accessible only by boat. The 73123 Army of the Eastern Theater Command Ground Force [zh] rushed to Poyang County to fight flood.
On the afternoon of 8 July, Qinghua Rainbow Bridge was devastated by flood. In the early morning of 9 July, the highest water level of Sandu Hydrological Station in Wuyuan County reached 62.74-metre (205.8 ft), exceeding the warning water level by 4.74-metre (15.6 ft).
On 17 June, heavy rain triggered mudslides and flooding that leaves 2 people missing in Danba County. 
From 18 pm 26 June to 1 am on 27 June, a sudden rainstorm occurred in northern Mianning County. National Highway 248 collapsed in the county seat Gaoyang Subdistrict [zh], causing two passing vehicles to fall into river. Only five of the ten passengers were rescued, two died and three were missing. As of 23:00 on 30 June, 14 people were killed and 8 people were missing in Gaoyang Subdistrict and Yihai Town [zh]. As of 1st July, 500 hectares (5.0 km2) of crops were affected, 280 hectares (2.8 km2) were damaged and 70 hectares (0.70 km2) will have no harvest, more than 280 houses collapsed or badly damaged and 2,300 houses partially damaged.
From the evening of 29 to 30 June, a heavy rainstorm occurred in Zhenxiong County, Yiliang County, Weixin County and Yanjin County. The level of Baishui River [zh], a tributary of the Yangtze River, had risen 8 metres (26 ft), causing serious floods in towns and townships along the river. As of 21:00 on 30 June, 3,871.54 hectares (38.7154 km2) of crops such as corn, potatoes and tobacco were affected, 3,745.09 hectares (37.4509 km2) were damaged and 84.68 hectares (0.8468 km2) will have no harvest, and more than 90 houses collapsed, 59 houses badly damaged and 90 houses partially damaged.
On 29 May, Chunan County suffered the strongest plum rain in history. On 8th July, the level of Qiandao Lake reached its highest level in history. At 9:00 a.m. on 8 July, Xin'an River Hydropower Station began to discharge flood. This is the first time since the completion of the hydropower station that all 9 gates have been fully opened for flood discharge.