Environmental activists and villagers Sunday warned of pollution of Beijing's water supply due to illegal trash dumping near Miyun Reservoir, which supplies about two-thirds of Beijing's drinking water.

Zhang Xiang, from environmental NGO Nature University, told the Global Times Sunday that he went to see the trash site Friday with local journalists after residents of Bingmaying village in Miyun asked them for help. The site is six kilometers from the reservoir.

A local government official from Miyun county told the Global Times Sunday that he had ordered a trash cleanup near the reservoir, a move he claimed was unconnected to media involvement.

It comes after a campaign by public service activist Deng Fei, in which he asked people returning to their hometowns for Spring Festival to post photos of polluted water sources, putting water pollution under the spotlight.

Zhang released the information on his Sina microblog Sunday.

"The dump is more than 60 meters long, 50 meters wide and around 15 meters deep. It's nearly filled with trash," said Zhang.

"Most of the trash is household waste, things like plastic bags, bottles, batteries and electric lamps," he said.

There is also another dump site, on part of the reservoir which is seasonally submerged, he said. 

"This one is only around 2 kilometers from the reservoir and it's been used for about two months. These dump sites will influence local residents' health and that of Beijing citizens," said Zhang. 

"The trash will rot and residue will gradually permeate into the groundwater and flow into Miyun Reservoir," he said.

Liu Zhengnan, an official with Miyun water bureau, said that they have sent a notice to the leaders of towns that sit in the upper reaches of Miyun Reservoir and local water bureau stations Sunday morning to inspect the area for trash dumping.

"We've told them to clean up all the trash they can find. I expect the job to be finished within a week," said Liu. 

"We frequently check the environmental conditions in towns near Miyun Reservoir. I didn't know about this dump site before," he said.

Ai Min (pseudonym), from Bingmaying village, under Bulaotun township, said that the dump site, which is only 500 meters away, started being used three years ago.

"It was construction trash, but later on all the household garbage from Bulaotun township was transported here. It smells awful and there are birds searching for food in the site," said Ai.

Ai alleged that many villagers had contracted cancer since the trash dumping started, so they raised their worries to the local government on January 15.

"In 2011, more than 30 people died and in 2012, more than 40 people died. They were both old and young people who died of diseases like lung and liver cancer," said Ai.

Ai noted that when they did not see any improvement, they then approached the Beijing Municipal Environmental Protection Bureau (EPB) and township environmental protection bureau on February 19.

"They came to see the spot on Thursday after I made repeated requests," said Ai, adding that the villagers use water from three wells which are less than 20 meters deep.

Zhang Junfeng, founder of NGO Happy Water Journeys, said that for those wells less than 60 meters deep, seeping trash pollutants could influence people's health.

"If the trash has many metal elements like those from batteries, people are likely to get poisoned and have cancer. The severe influence can be seen within five years," he said.

Zhang noted that for Beijing citizens who drink the water that has been processed by water companies, the water quality can be guaranteed. "However, the processing cost will be higher because of the pollutants," he said.

Zhang stressed that the Beijing government should take responsibility to protect Miyun's water quality by giving money to local citizens to collect their trash and deal with it properly.

The EPB said via its microblog Sunday afternoon that they have urged Beijing environmental inspection team and Miyun EPB to investigate the trash site and publish the results publicly.