China needs more professionals to conduct regular inspections of thousands of small-and medium-sized dams in rural areas, as an earlier-than-usual flood season is posing challenges to dam safety.

"Heavier rainfall caused by climate change poses threats to dam safety that have been ignored, especially in rural places in southern China," said Ni Guangheng, director of the Institute of Hydrology and Water Resources at Tsinghua University.

Inflow from the upper streams of the Yangtze River has hit an eight-year high, forcing the Three Gorges Dam to discharge more water and brace for floods earlier this month.

While the state-owned Three Gorges Dam and the Gezhouba hydropower plants will receive regular inspections, there might not be enough professionals to conduct inspections on the smaller dams, which were built in the 1950s and lack regular maintenance, said Wu Suhua, a senior engineer at the Dam Safety Management Center under the Ministry of Water Resources.

Dozens of small dams in Wenchuan county in Sichuan province were severely damaged and some collapsed in a 2008 earthquake, Wu said.

Even though the exact number of needed inspectors is hard to calculate, Wu said China must fill the gap left by a lack of training and attention to the hidden trouble.

"We hope that with well-planned designs and regular maintenance, the dams are able to tackle any future challenges that may occur hundreds of year after the project is done," Wu said.

Patrice Droz, coordinator of the Dam Safety Enhancement Program between China and Switzerland, said China should put more emphasis on maintenance and early identification of measures needed to address potential dangers.

The cooperative program between the two countries was created in 2009 and has helped train 300 professionals in China, Droz said.