A Zhejiang entrepreneur is offering a 200,000 yuan reward to a senior official if he swims in a polluted river for 20 minutes, as part of an attempt to draw attention to the environmental plight in China's eastern province. Jin Zengmin, chief executive of a Hangzhou eyeglasses retailer, announced the reward on China’s Twitter-like social website on Saturday. “If the environmental protection bureau chief dares to swim in [Ruian's] river for 20 minutes, I will pay [him] 200,000 yuan [HK$246,000],” Jin wrote on Sina Weibo. In three photos Jin posted, a river in small-town Ruian is seen entirely blocked by floating rubbish. Jin blamed a rubber overshoe factory for dumping industrial waste into the river. This river was where villagers used to wash vegetables and clothes in his childhood, Jin told Chinanews.com . Asked for comment, Ruian’s environmental protection bureau chief, Bao Zhenmin, acknowledged the river was polluted, the report said. But he said the rubbish is from people, and not factories. “Overpopulation of this region is the main reason behind the pollution…[The population] has largely exceeded the local environment’s capacity,” Bao told Chinanews.com. According to Bao, the Xianjiang area where the river flows has 44,000 residents, but the migrant population amounts to 80,000 alone. Zhejiang province and its many factories draw hundreds of thousands of migrants from across the country every year. Bao also told Chinanews.com that a complete water recycling system will be in place within three years. The plan includes a trash recycling site and disposal water treatment plant. On Sunday, a Shandong environmental protection bureau announced a 100,000 yuan reward for information about an underground pollution case.