According to data from the Shanghai Shipping Exchange, the world's busiest box port handled 3.27 million TEU in April, up five per cent year on year, while neighbouring Ningbo-Zhoushan handled two million containers, up 17 per cent, reported IHS-Fairplay.
Throughput at China's top eight container ports rose by six per cent in April, bringing total volumes in the first five months of the year to 51.23 million TEU, an increase of 6.2 per cent compared to the same period last year.
Strong port traffic reflected strong growth in the value of April's exports and imports, which jumped eight per cent and 11.9 per cent, respectively, in US dollar terms.
On the Pearl River ports posted an even better performance in April with volumes up 10.7 per cent year on year at the Port of Guangzhou and by 4.6 per cent at the Port of Shenzhen.
Hong Kong had another stellar month with throughput rising 12.7 per cent to 6.66 million TEU, following throughput gains of 11.9 per cent and 13.7 per cent in February and March.
Yet, volumes at the main eastern and northern ports of Xiamen, Qingdao and Dalian remained flat in April.
But higher volumes through the Port of Shanghai meant growing delays which have plagued vessel calls since the beginning of April when a combination of rising throughput, mega shipping alliance port call reshuffles and bad weather reduced terminal productivity.
A major cause of the delays was said to be over-booking by shipping lines, resulting in containers having to wait at the terminal until the next available departure. Aside from making the congestion worse, the slower turnover and efficiency of terminal operations led to a shortage of empties at inland depots.
Shanghai International Port Group has been trying to address the capacity issues and by shifting some port calls from Yangshan to other terminals. Shippers have also been rerouting cargo to other ports including Ningbo-Zhoushan.
In a separate development, the manufacturing sector expanded at a slower pace in April. The National Bureau of Statistics' Purchasing Managers' Index (PMI) dropped to a six-month low of 51.2 from a five-year high of 51.8 in March. In addition, the Caixin/IHS Markit Manufacturing PMI that measures the performance of small-and-medium sized manufacturers fell to 50.3 in April.