Weeks of heavy flooding in northern Vietnam has not only resulted 17 deaths and the loss of millions of dollars in damages, but also besieged Ha Long Bay with toxic slurry from nearby coal mines.

A week of constant rain in Quang Ninh Province has displaced thousands of residents as toxic materials were released from inadequate holding ponds at 16 open pit coalmines and three coal-fired plants, writes ABC.

Coal mines near Ha Long Bay.

According to a statement from international clean water resources environmental group Waterkeeper Alliance, these waters are loaded with potentially hazardous heavy metals including arsenic, boron, barium, cadmium, chromium, lead, manganese, selenium and thallium.

Workers in Quang Ninh Province struggle to pull coal from raging floodwaters. Photo via VnExpress.

The organization said that waters containing these toxic materials had inundated the Lang Khanh Harbor and Dien Vong River that connect directly to Ha Long Bay.

Another shot of workers in Quang Ninh Province struggling to pull coal from raging floodwaters. Photo via VnExpress.

"We are deeply concerned by the pace of this unfolding disaster and its sheer scale," said Robert Kennedy, president of Waterkeeper Alliance.

Recent rainfall in the province has been the heaviest in 40 years, reaching 800 millimeters in some areas. Two families on Mong Duong District were killed when a toxic mudslide swept away their homes on July 26. The entire community was buried in up to two meters of sludge from a nearby mine, reports Thanh Nien.

The aftermath of a toxic mudslide. Photo via Thanh Nien.

"We have nothing now, as the house and all our assets are in the mud. We don't know what happens next," a local primary school teacher told AFP.

Ha Long Bay, recently referred to as a “polluted and unpleasant tourist trap” by Thanh Nien, can ill afford another threat to its environmental health, especially given how long cleanup of toxic materials has taken in the past.