Farmers in Southeast Asia face increased pressure to feed the region during the pandemic, but on top of record droughts and climate change, they’re now facing impacts from sand mining.
“This land was mine, it eroded slowly from the riverbank and after a while, the whole chunk of land totally collapsed,” Than Zaw Oo, a farmer on the Salween River in southeastern Myanmar’s Mon State, told Reuters recently. He said he’s lost three-quarters of his land to erosion and is now a few thousand dollars in debt from paying for embankments to try to preserve his farm.
As COVID-19 shakes economies and lockdowns leave many without income, the pandemic raises questions about the security of our food supply. Agriculture in Southeast Asia is so far stable, though the region’s farmers were already struggling with significant challenges from drought and climate change before the pandemic hit.
But farmers are now also seeing impacts from sand mining, a sprawling industry fueled by demand for concrete and glass for cities and infrastructure projects.
Along rivers and off coasts throughout Southeast Asia, miners use dredging machines to extract the sand, piling it on barges to be sent to megacities like Bangkok and Jakarta or further afield. The world’s largest sand importer is Singapore, which uses it for land reclamation projects. The biggest sources for sand mining in the region are Cambodia, Indonesia, Malaysia, Myanmar and Vietnam.
According to a UN Environment Programme (UNEP) report, the global demand for sand has tripled over the past 20 years to around 50 billion tonnes per year, more than any other natural resource. The same report shows that sand extraction drives pollution, flooding, lowering of aquifers and drought.
The impacts of sand mining make Southeast Asia’s food system less resilient and make farmers in the region more vulnerable to the impacts of both climate change and shocks like the COVID-19 pandemic.
As sand is scraped from riverbeds, it changes the hydrology of the river and damages its ecosystems. It destroys fish habitats and removes nutrients needed for animals as well as agriculture. Riverbed mining also drives erosion, both along the rivers where dredging occurs and also along coastlines, where sediment from the rivers normally replenishes the land. In river deltas, the impacts of dredging expose farms to the threat of saltwater intrusion.
Southeast Asia’s farmers are losing land to erosion
Erosion from sand mining is wearing away at the land of farmers like Than Zaw Oo and it may be jeopardizing Myanmar’s food supply. Residents along the Salween and in the Irrawaddy River region, where Myanmar grows the majority of its food, have told reporters and researchers that erosion has quickened rapidly since sand mining took off.
Marc Goichot, an Asia Pacific water expert at WWF, told Frontier Myanmar that researchers from his team found the Irrawaddy Delta has already been worn away by the removal of sediment from the river system. In 2008, the delta was wracked by Cyclone Nargis, which left at least 138,000 dead. Goichot said that if the delta, a major food producing region, were hit by a similar storm today, the impact would be much greater. As climate change drives more frequent and more intense storms across the region, the risk for depleted deltas like the Irrawaddy increases.
The current sand mining boom in Myanmar has taken off in part because the Philippines, Malaysia, Cambodia and Vietnam have restricted or banned exports of sand to Singapore, driving up demand in Myanmar.
Sand mining allows salt water to swamp river delta agriculture
The impacts of sand mining also make the region’s vital and vulnerable river deltas vulnerable to saltwater intrusion from rising seas, especially the Mekong Delta in Vietnam. The Mekong Delta is one of Southeast Asia’s most productive agricultural regions and is vital to the regional and global food system. Home to 20 million people, it produces nearly one-fifth of the world’s rice.
But as sand mining deepens riverbeds in the delta, it allows saltwater to intrude further and further into the river system during the annual dry season. Deeper riverbeds and lower flows also mean that the saltwater stays in the delta longer, killing crops. Between smaller harvests and less income for farmers, the intrusion of saltwater poses a major threat to agriculture in the delta: this year, it damaged crops as far as 110 kilometers inland.
The problem is exacerbated by drought and record-low water levels in the Mekong and in Cambodia’s Tonle Sap Lake, normally the source of about one-third of the delta’s water supply. Without that added flow in the river, the saltwater is expected to push up 30-40% further into the delta during this year’s dry season.
The delta is also more vulnerable to hydrological changes than previously thought, as a 2019 study at Utrecht University in the Netherlands showed that the elevation of the delta is on average only 0.8 meters above sea level, two meters lower than earlier measurements suggested.
According to WWF and the Mekong River Commission, mining extracts over 55 million tonnes of sand from the Mekong every year—almost double the amount naturally carried by the river. But the amount of natural sediment is also dropping quickly with the construction of hydropower dams: a study by UNEP and the Stockholm Environment Institute in 2017 showed that if Mekong governments continue with the 11 dams planned for the mainstream of the Mekong, it could block 94% of the river’s sediment from reaching the delta.
The riverbed in many parts of the lower Mekong is dropping by 20-30 centimeters per year. Between sand mining and the impacts of dams, the Mekong Delta could lose much of the sediment that prevents it from being scoured by salt water.
High demand drives illegal mining, even during COVID-19
Indonesia, Cambodia, Malaysia and Vietnam have all adopted bans or regulations on sand mining, some specifically targeting trade with Singapore. But much of the industry is illegal: between 2007 and 2016, only 3.5% of sand exported from Cambodia to Singapore was recorded by the Cambodian government.
In Vietnam, the rate of illegal sand mining increased significantly during the country’s COVID-19 lockdown, according to local residents. Residents of Hanoi’s Ba Vi District reported a large increase in the number of sand mining barges in their area of the Red River. Locals in the southern province of Binh Phuoc reported similar increases, with trucks entering and leaving their community every day.
Vietnamese authorities have tried to crack down on illegal mining and have caught a number of violators but the problem persists as before. The government’s next plan is to raise fines on illegal mining and possibly amend laws to reclassify the crime as theft.
But in an otherwise precarious economy, sand mining offers quick payouts. A load of sand can bring in US$700-1000, compared to the average Vietnamese income of $269 per month. The price of sand is also rising fast—in Vietnam, the price of sand quadrupled in 2017. With the economic impacts of the pandemic, governments that crack down will have to support sand miners to find alternative livelihoods.
From erosion to saltwater intrusion, riverbed dredging introduces new risks that make farmers in the region more vulnerable—at a time when many people are worried about the stability of our food supply. Sand mining is putting Southeast Asia’s agriculture in jeopardy, and without careful regulations, strong enforcement and steps to reduce demand, farmers in many areas will struggle to feed the region.