Shallow groundwater in Jiangsu province is slightly polluted, according to a survey published by the province's geological survey institute.

Launched in 2006, the survey is said to be the first of its kind to analyze underground water pollution in the prosperous province in East China.

More than 3,000 hydro-geological investigation zones and 1,441 pollution sources were included in the survey, which studied the distribution of water pollution in the province.

It found that deep phreatic waters in the province can be used as sources of drinking water, but the quality of shallow underground water is "not great", partly due to illegal pollution discharges.

Despite the abundant rainfall in the region, illegal pollution discharges are widespread and it's necessary that the government further enforces anti-pollution legislation and protects the underground water resources, said the survey.

In addition, it's also important to set up an alert system for underground water pollution, it said.