China has in the last month or so launched a new construction project on Triton Island in the Paracels. Triton is the southwestern-most of the Paracels and therefore the closest to Vietnam, which makes the waters and airspace around it particularly tense. For instance, Triton, and competing claims from it, played an important role in a monthslong 2014 standoff between the two over China’s deployment of a deepwater drilling rig. This strategic position has led to speculation that a raised strip of land visible in recent satellite imagery of Triton could be the beginnings of an airstrip meant to project power toward Vietnam. But that is unlikely.

Triton Island, August 17, 2023

The strip of land in question is much smaller than China’s four existing runways in the South China Sea, at nearby Woody Island in the Paracels and Fiery Cross, Mischief, and Subi Reefs in the Spratlys. Each of those is about 3,000 meters long and 50 meters wide. This hypothetical new airstrip on Triton is just 600 meters long and 15 meters wide. That is far too small for fighter jets, surveillance aircraft, or military transports of any size. Even if China continued to extend it to the edge of the island, it would measure just 930 meters long. Additionally there are no signs of taxiways or an apron. Small prop planes or drones could theoretically make use of an airstrip of this size. But China’s large airbase on Woody Island is barely 100 miles away, and Triton already has a helipad and port to ferry supplies and personnel.

A more plausible explanation is that this strip of land is just that—an embankment or elevated roadway connecting the existing base on Triton Island to new planned facilities. Two extensions have already been constructed southward from this strip of land, with construction well under way on a large building of unknown purpose at one of them. Triton’s geography helps explain why this is necessary.

Triton Island, July 4, 2015 

The island is extremely low-lying and prone to frequent seawater inundation. While it theoretically covers 290 acres, satellite imagery shows that the majority of the island is often flooded for long stretches. That is probably why China has only ever built on a relatively small, and presumably stable, patch of land in the southwest corner of the island (on which it has also planted vegetation, which has likely helped prevent erosion).

Triton Island, November 6, 2021

In fact, since 2021, portions of the northern shore of the island have been progressively lost to the sea. And a close look at recent imagery of this newly built, elevated strip of land shows seawater collecting along both of its edges.

Triton Island, August 17, 2023

China does seem to have new ambitions for Triton Island. The fact that a large cement plant has been added to the existing base attests to that. And this new elevated roadway and those extending from it southward seem like a necessary first step to keep the island’s regular flooding at bay and allow construction of new facilities. What those will be is still unclear, but an airstrip is neither the most likely nor more useful option.