As real estate building increases across the world, so too does the illegal extract of sand, which results in serious environmental impacts.

(Photo: Lillian Suwanrumpha/AFP/Getty Images)

Every day, miners remove 5,500 to 6,000 truckloads of sand (about 20 tons each) from the scenic beachfronts and 17 river basins of Tamil Nadu in India, according to the state government.

India is hungry for sand. Fueled by a real estate boom estimated to generate $180 billion annually by 2020, India is digging 500 million metric tons of sand every year, feeding an industry worth more than $50 billion. And India's hunger is bound to increase, as the government plans to build about 60 million new affordable homes between 2018 and 2024.

But this sand boom has left locals and ecosystems hurting: river and beach-dependent communities in Tamil Nadu see their livelihoods continuously threatened, while habitats and local food chains lose their balance.

"Beach sand mining is taking place within the high tide line, inside the sea," says Sandhya Ravishankar, an independent journalist from Chennai, the state capital, who covers sand mining in the region. She adds that the mining occurs within the coastal regulation zone, an area ostensibly off-limits for such activity.

The World's Disappearing Sand Castle

India isn't alone. Massive sand mining operations stretch across Southeast Asia and Morocco, South Africa, and as far as the United States and the Caribbean. At a global level, the amount of natural resources used in building real estate and transportation infrastructure in 2010 was 23 times higher than in 1900, almost 80 percent of it sand and gravel, according to a recent study in Science.

"The community researching sand mining is still very small," says Jianguo Liu, professor of fisheries and wildlife at Michigan State University, and one of the study's authors. "We are trying to bring awareness through this paper."

As a commodity, sand is especially vulnerable to illegal mining. It's a common resource, seemingly abundant and expensive to regulate, which, according to the researchers, exposes it to illegal extraction. In Tamil Nadu alone, for example, nearly three-fifths of the sand mined over the past 17 years was done so illegally, alleges a report submitted to the Madras High Court.

Environmental impact assessments have failed to shine a light on the real impact of mining in Tamil Nadu, Ravishankar says. Consequences include groundwater depletion, loss of agricultural land and farm employment, loss of water resources, and road and bridge damage, according to the state's Campaign for the Protection of Water Resources.

Losing farmland undermines food security. Sand beach mining exacerbates seawater intrusion, which compromises land productivity and freshwater supplies, displacing people who no longer have access to basic resources.

Sand extraction can also leave people at the mercy of extreme weather events such as storm surges and tsunamis by stripping away their buffer against sea level rises, according to the paper in Science.

Furthermore, sand mining leads to health hazards such as malaria, carried by the mosquitoes that breed in the mining pools left behind, research shows. Other impacts may be due to pollution.

Across India, sand mining also takes a toll on miners, according to a recent report from the Thomson Reuters Foundation.

Sandy Corruption

Different laws govern the exploitation of beach and river sand in Tamil Nadu. Since 2013, the state completely banned the mining and exporting of beach sand, though if anything the pace of exploitation seems to have increased: exports from the state in the four years since the ban was imposed average 550,000 metric tons a year, compared to 431,000 metric tons a year on average in the 13 years before the ban, according to the report submitted to the high court.

The problem isn't a lack of laws, but of enforcement, according to Sibi Arasu, another investigative journalist deeply interested in the issue. He says that both the national and state governments have powers to regulate it, along with the Ministry of Environment, Forests, and Climate Change, and Tamil Nadu's Department of Mines.

But action against illegal mining is often nipped in the bud. Investigative reporting has repeatedly exposed how sand is plundered with the collaboration of state authorities and politicians, with no regard for the impact on local livelihoods. This is why the Campaign for the Protection of Water Resources also includes human rights violations in its list of the effects of sand mining.

"Elected representatives, big landowners or those with great clout in the local community are inevitably involved in sand mining," Arasu says. "There is also usually widespread fear of sand miners, and protesting against mining leads to disastrous and sometimes fatal consequences."

Local media has reported on killings allegedly linked to sand mining, while several journalists covering the topic have been threatened.

Demand for sand will continue to increase, the Science study warns. It calls for further exploration into what happens to sand from extraction to final use, who is accountable locally and remotely, and finally calculating a global sand budget.

Authorities should also focus on regulating the mining industry and enforcing existing rules, while recognizing the ecosystem services sand provides by putting a value on its use, the study says.

In Tamil Nadu, hope is not lost. In late November of 2017, the Madras High Court demanded the state government end sand quarrying within six months, ruling that no new quarries and mines should be opened.

But India is just one of three countries leading the global construction boom, along with China and the U.S., according to PricewaterhouseCooper's "Global Construction 2030" report. Construction is estimated to contribute 14.7 percent of global gross domestic product in 2030, with construction volume set to grow by 85 percent during this period. The top three countries will account for more than half of that growth, with India's construction market predicted to grow twice as rapidly as China's in the next 12 years.

Though recycling can be an option to make sand use and trade more efficient, without innovative, affordable alternatives, sand resources will continue to be under fire, the researchers say.

One option being explored is manufactured sand, or M-sand, created by crushing rocks such as granite or basalt at high speeds in a process that emulates river sand production. But the resulting particles can have a rougher texture and sharper angles than natural sand grains, potentially affecting the quality of the concrete in which they are used, and thereby the structural integrity of buildings and other structures.

Ongoing research is trying to find ways to create M-sand that more closely resembles the original. Environmental impacts are also an issue here. Quarries are usually located far from manufacturing and consumption points, leading to high costs in transport. Producing M-sand also requires more energy than mining traditional sand. While M-sand is cheaper and faster to produce than natural sand, Indian construction companies—and many others—still prefer the real thing.

"At the end of the day, since there is high demand for river and beach sand in the booming construction industry, and the alternative, manufactured sand, is considered substandard, there is always a search for a new source of river sand," Arasu says.

This story originally appeared at the website of global conservation news service Mongabay.com. Get updates on their stories delivered to your inbox, or follow @Mongabay on Facebook, Instagram, or Twitter.