Quang Ninh authorities have intercepted two ships in the act of illegally discharging mud into Ha Long Bay, a World Heritage Site.

About 300cu.m of mud was reported to have been transported from Cai Lan Port and then dumped into the sea last Thursday. The Ha Long Bay Management Department has sent a document asking port authorities to control dredging to prevent ships from releasing waste into the bay.

"This action not only seriously contaminated the site, but implicitly endangers vessels on the bay because the water is shallow," said deputy head of the department Do Duc Thang.

"It's easy to discharge mud into the sea. Vessels pretend to operate normally on the surface but, in fact, they are ejecting waste matter underneath."

In 2012, a ship was also caught dumping mud, but the owners only received an administrative punishment.

Although further investigations into the impact on the environment are needed, this act indicates that much more needs to be done.

"The biggest problem for Ha Long Bay is the conflict of interests between protecting and preserving the heritage and developing industry and tourism," Quang Ninh Party Committee Secretary Pham Minh Chinh told Sai Gon Giai Phong (Liberated Sai Gon) newspaper.

"The matter is how to conserve the site while tapping its full potential so we can reinvest in its protection."

During his tour of Ha Long Bay on November 8, Paul Dingwall from the International Union for Conservation of Nature (IUCN) hailed the province's efforts to conserve the site.

He stated that UNESCO reports of negative impacts to the heritage site including industrial development, environmental pollution, increased tourism and broken biodiversity were not true, according to Quang Ninh newspaper.

Pham Quang Phong, general secretary of the Vietnam National Committee for UNESCO, said Dingwall's report would be a reliable source to stop the site being removed from the heritage committee's list of recommendations at its next session in 2014.

With its outstanding natural beauty, Ha Long Bay was officially placed on the list of the World Natural Heritage Sites in 1994 and then recognised as a World Heritage for the second time in 2004. The site receives an average of five million domestic and international visitors each year.

There are usually 450 tourist vessels in the bay, 150 of which are equipped with overnight accommodation facilities.

Reports received by the IUCN indicate that unregulated tourism boats operating in the bay, increasing visitor numbers and the absence of regulations contributed to negative impacts from tourism.

UNESCO's World Heritage Centre and the IUCN remain concerned that this has led to a market saturated with irresponsible tour operators unconcerned with environmental issues.

Accordingly, the five main issues potentially threatening the World Heritage value of the bay are population growth, increased tourism pressure and development, urban and industrial development, lack of financial and technical resources, and the absence of integrated planning.

Quang Ninh provincial People's Committee has issued a decision approving investment for environmental protection projects in Ha Long city.

It has also established a tourism inspection force with the involvement of officials from its tourism, environment, transport and construction departments

However, these efforts seem insufficient. The heritage committee and the IUCN still require an integrated management approach because "the lack of an integrated approach makes it extremely difficult to successfully address multiple pressures in the long term".

In its State of Conservation report (2013) for the site, UNESCO noted that "the threats, including water pollution, represent an ongoing risk to the property and require constant vigilance".-VNA