NANNING -- The heat wave hitting southern China has raised concerns over irrigation systems in the country's poorer regions, with crops failing due to poorly maintained irrigation facilities.

The drought in Guilin city in South China's Guangxi Zhuang autonomous region has affected six counties since July, with 47,000 local residents facing drinking water shortage.

According to local authorities, about 22,000 hectares of crops have been damaged across the region.

Irrigation systems, which depend on run-off and underground water sources, have been paralyzed by the persistent drought.

"The constant heat causes reduced water storage in local reservoirs and reduces underground water levels. The irrigation facilities have been in operation for over 40 years and haven't been maintained," said Tang Xiaojun, head of the water resources bureau in worst-hit Quanzhou county, one of the largest grain-producing areas in Guilin.

"Crops have been hurt by the breakdown of irrigation facilities," Tang added.

In Zibeichong village, the worst drought since 1953 has exposed problems with local irrigation facilities.

About one million cubic meters of water in a reservoir four kilometers away was wasted because the channel was blocked, said Feng Shibao, head of the villagers' committee.

"We are not prepared for extreme weather like this," Feng added.