The water flow at Wubu Hydro Station in Wubu County in Yulin City, in Shaanxi, reached 10,600 cubic meters per second on Friday, the highest level since 1989, the State Flood Control and Drought Relief Headquarters said.
Recent torrential rain has seen water levels rise on the main artery and tributaries of the Yellow River's middle reaches, said the flood control authority.
Famous tourism sites along the river, such as the Hukou area in Shanxi, have been closed to tourists until the alerts are lifted, said the authorities.
Downstream, Longmen Hydro Station recorded a water flow of 7,620 cubic meters per second at 7am yesterday, the highest level since 1996, it said.
Flood water has inundated low-lying areas and some water control and diversion projects, said officials.
The headquarters said residents in areas threatened by flooding have been relocated and that the two affected provinces have dispatched emergency personnel to strengthen checks on dams and increase flood control materials.
Rainstorms in Beijing last weekend killed 77 people, triggering public anger, with questions asked about emergency planning and the poor drainage system in big cities like the capital.
In the aftermath of the Beijing deaths, as the flood peak hit parts of central China, the authorities had demanded the quick evacuation of affected areas.
Meanwhile, train services on parts of the Southern Xinjiang Railway in northwest China's Xinjiang Uygur Autonomous Region were suspended yesterday due to flooding, said the railway operator.
Flood water has covered sections of the track, halting services on the Turpan-Korla stretch of the railway line, said railway officials.
Hundreds of rescuers are working at the site and trapped passengers have been transferred from the area, said officials.
"Luckily, the train stopped in a small station where supplies were available," said a train passenger, surnamed Li, who yesterday had been trapped for hours on a train in Xinjiang.
But other passengers were unable to stock up on provisions. One female passenger stranded on a train complained yesterday that she had eaten nothing since embarking on her journey.