A banned trade, a protected river, and the ambitious reclamation plan quietly depending on both.
The Trapeang Rung River isn’t somewhere most people have heard of. It flows through Koh Kong province in southwest Cambodia, past mangroves and lowland forest, home to one of the world’s least understood otter species, the endangered hairy-nosed otter, before reaching the sea. Since April 2026, it has also been where activists say Cambodia’s sand export ban has quietly come undone.
What the activists actually found
Cambodia banned sea sand exports outright in 2017, after an earlier scandal in which Singapore was found to have imported roughly $752 million worth of Cambodian sand while Cambodia’s own government reported just $5 million in exports over the same period. The gap alone told its own story about how little of this trade was ever officially tracked.
In July 2026, the environmental group Mother Nature Cambodia photographed sand mining barges bearing the logo of Catalyst Marine and Resources operating on the Trapeang Rung, a company registered in Cambodia since December 2024 and, according to Mongabay’s investigation, linked to Starhigh Asia Pacific, a Singaporean firm active in sand mining across the region. Mongabay tracked the barges to two bulk carriers anchored off Koh Kong Krao, Cambodia’s largest island, and used AIS ship-tracking data to identify one of them, the Maltese-flagged Densa Dolphin, as one of four vessels that made the same journey from Cambodia to a land reclamation site at Singapore’s state-developed Tuas Port between June and July 2026. An independent radar analysis by Earth observation scientist Magdalena Smigaj found dredging vessels had been consistently active on that stretch of river since late April, around the same time provincial officials publicly marked the launch of Catalyst’s operations.
A ban that may not really be a ban anymore
Here’s where it gets genuinely murky, not smuggling in the usual sense. A provincial mining official in Koh Kong told Mongabay directly that the 2017 export ban had been lifted, and that the office had issued Catalyst a dredging licence in 2025. Cambodia’s national mines minister, for his part, defended sand mining in general terms as important for navigation and construction, while declining to address whether exports to Singapore specifically had resumed.
So the honest picture isn’t “banned trade sneaking through the cracks.” It’s a provincial permit that may or may not carry any real legal weight, a national ministry that won’t confirm or deny the specific claim, and an activist group that has already paid a heavy price for asking the question. Mother Nature Cambodia has fought sand mining in this exact province before; members have previously served prison sentences over their campaigning, and five members convicted in 2024 on charges widely viewed as politically motivated were reported to still be in prison as of July 2026, the most recent date this could be confirmed.
Why Singapore needs an answer nobody’s giving
The Singapore side of this story rarely gets told alongside the Cambodian side, and it’s the part that makes this more than a one-country problem. At this year’s National Day Rally, Prime Minister Lawrence Wong laid out a reclamation vision reaching fifty years into the future: a new Western Island formed by joining Semakau, Bukom, Sudong and several smaller islands, further reclamation at Pulau Tekong, and the long-studied 800-hectare Long Island project off the East Coast. As one detailed analysis of the announcement pointed out, every major regional sand supplier Singapore has historically relied on is now either banned, restricted, or, as in Cambodia’s case, legally unsettled. The speech never addressed where the sand for any of it will actually come from.
Singapore has built roughly a quarter of its current landmass through reclamation since independence, and has been the world’s largest sand importer for two decades running. None of that makes it uniquely culpable, land-scarce nations reclaim land, that’s not news. What’s worth sitting with is the gap between a fifty-year national vision announced with confidence and a supply chain nobody in that speech was willing to name.
Singapore’s container port operations. Tuas Port, the reclamation-dependent expansion at the centre of the country’s fifty-year plan, will eventually consolidate all of this into a single site
What responsible tourism looks like in the middle of this
None of this is a reason to avoid the Cardamom Mountains. If anything, it’s a reason to look more closely at who’s operating there and what their money actually does.
Cardamom Tented Camp, a nine-tent lodge on an 18,000-hectare concession inside Botum Sakor National Park, exists specifically to fund the kind of protection this story is about. A three-way partnership between the Minor Group, YAANA Ventures, and Wildlife Alliance, the camp funds sixteen Wildlife Alliance forest rangers whose patrols protect the concession from illegal loggers, poachers, land grabbers, and sand dredgers by name. Wildlife poaching in the area has fallen by roughly 80% over seven years, and populations of Asian elephants, smooth-coated otters, leopards and hornbills, verified by Wildlife Alliance and the Golden Triangle Asian Elephant Foundation, have recovered as a result. It isn’t the only model working in the region either. The Chi Phat community, on the Phiphat River in Koh Kong province, has run a similar programme since 2007 in partnership with Wildlife Alliance, training local families to run guesthouses, homestays and guided tours, with roughly 80% of revenue going directly to those providers while also funding anti-poaching patrols. Further northeast, the Steung Areng community is developing its own version of the same model.
Lodges like Cardamom Tented Camp fund the ranger patrols that stand between the Cardamom Mountains and exactly this kind of extraction.
That’s the actual choice sitting underneath this story. Two supply chains run through the same forest, one funds the rangers protecting it, gets verified by outside conservation groups, and puts tourism revenue on record. The other runs through a provincial permit nobody at the national level will confirm, tracked only because an activist group risked prison to photograph it. Booking the first doesn’t undo the second, but it’s a genuinely traceable way to put money on the right side of it.
Cambodia’s Ministry of Mines and Energy has not addressed Mongabay’s specific findings at the time of writing. We’ll follow this if that changes.
Further Reading
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