Report: Chinese Trawlers are Dumping Sewage Near Philippine Reefs

Ship positions by visible-spectrum imaging (left) and chlorophyll trails (right) (courtesy Simularity / ESA)

Published Jul 13, 2021 7:53 PM by The Maritime Executive

The Philippines Department of Defense announced Tuesday that it has called for an investigation of the environmental impact of effluent discharged by Chinese state-backed fishing vessels, which have established an unwelcome presence inside the Philippine EEZ in the Spratly Islands.

The statement follows a new report from the U.S.-based geospatial intelligence company Simularity, which has used satellite imaging to identify telltale green chlorophyll trails near suspected Chinese fishing vessels. The trails may be indicative of algae blooms caused by sewage discharge, according to Simularity head Liz Derr - and as the vessels are stationary, the impact on the local environment could be cumulative. 

"When the ships don’t move, the poop piles up," Derr said in a recent presentation. "The hundreds of ships that are anchored in the Spratlys are dumping raw sewage onto the reefs they are occupying."

Derr claimed that biodiversity on nearby reefs has decreased due to an overgrowth of algae, and she warned of impending disaster. "Damaging these reefs directly affects the fish stocks of the entire South China Sea and can lead to a hunger crisis in coastal regions and a collapse of commercial fishing in the South China Sea," she asserted in the presentation.

The Philippines' Department of Environment and Natural Resources (DENR) has pledged to work with defense and coast guard officials to verify the accuracy of Simularity's report and determine if the vessels in question are indeed Chinese. "After that, we will be seeking for the attention of the Chinese government through our [Department of Foreign Affairs," said DENR Undersecretary Benny Antiporda in a statement. 

The quantity of effluent has been previously estimated by Captain Carl Schuster (USN, ret'd.), who has suggested that these midsize fishing vessels each generate about 10 pounds of waste per day. For recent Chinese vessel counts at Union Banks, this would amount to about 2,400 pounds per day in total, or roughly 30 tonnes per month.

"China treating us as its toilet is a clear violation of both international and local environmental laws," said Philippine Senator Grace Poe on Tuesday. "If the laws of men are not enough, basic laws of human decency demand that we do not submit to this debasing treatment."

China claims the overwhelming majority of the South China Sea as its own, including Philippine-claimed segments of the Spratly Islands. In March, a flotilla of state-sponsored Chinese maritime militia vessels deployed to waters just off Whitsun Reef in the Union Banks area, anchoring by the hundreds at a position just offshore. After protests from the Philippine government, the large trawlers dispersed, but about 230 remain in the Union Banks lagoon, according to Simularity. 

The report coincides with the fifth anniversary of a pivotal ruling from the Permanent Court of Arbitration in the Hague, which found in favor of the Philippines and invalidated Chinese claims to the Philippine EEZ. China regards the ruling as illegitimate "waste paper" and continues to pursue maritime dominance in the region.