A winter of heavy storms and flooding, especially in late December, has washed away vast stretches of protective sand dunes and bathing beaches on Germany's North Sea islands.

Coastal areas on islands such as Sylt, Borkum and Norderney, which together attract millions of tourists, will need to be rebuilt before the summer holidays — an extensive and expensive procedure.

In what's known as beach nourishment, load after load of sand will be moved in to reconstruct depleted coasts. The state government in Lower Saxony, where Borkum and Norderney are located, has already said it will provide up to €700,000 (about $760,000) to literally shore up the region's main moneymaker.

Does rebuilding beaches harm the environment?

Sand to replenish North Sea beaches likely won't come from too far away. In previous years, it's been sourced from further down the shore or from neighboring islands. As one official told a local news outlet in 2017, the sand "isn't gone, it's just somewhere else."

The island of Sylt, for example, has replenished beaches with sand from the ocean floor for the last 40 years.

Dredging ships suck up a mixture of sand and water from the seafloor in an area about 8 kilometers (5 miles) from the shoreline. They dump that sand on the beach and in offshore reef zones, which helps reduce the power of incoming waves.

While better than using sand shipped in from the other side of the world, this method has consequences for coastal and river ecosystems: Scooping up all that sand can destroy underwater life and disrupt nesting sites for birds and other animals.

It can also make coastal erosion and landslides — which are already increasing due to climate change — more likely in the long run.

As sand is removed from the ocean floor, coastal sand will eventually flow away from the shore to fill the gap left by what's been removed. This causes the beach to retreat even further. And beach nourishment is never permanent — before long, added sand will be washed away and more will be needed.

Sand can be supplied from other places, though, to avoid the environmental impact of offshore dredging. Cities like Manila in the Philippines and Miami in the US, for example, use sand from inland sand mines, quarries or rivers and lakes. But experts have warned that it is vital to use sand that closely matches the composition of the specific beach in question to avoid potential contaminants and protect flora and fauna that have adapted to a specific sand type.

Why is sand such an important resource ?

After water, sand is the second-most-used resource on Earth, according to the UN Environment Program. But it isn't needed only to rebuild beaches. Regular sand — a natural mix of crushed rock, minerals and other organic material found at the bottom of lakes, rivers and the ocean — is vital in the construction sector, and is used to make glass and concrete.

It's also used to create new land in major metropolises like Singapore and China's Hong Kong and Shanghai, where space is at a premium.

Silica, a type of specialized sand, is used to make silicon — a key ingredient in circuits and microchips.

Germany imports significant shiploads of sand every year. In 2022, the country brought in around 1.55 million metric tons (1.71 million US tons) of both regular and specialized sand, according to the data-gathering platform Statista. It ranks among the world's top 10 sand importers, along with the United States, Belgium, the Netherlands, Canada and China, the world leader.

Are there alternatives to sand?

Even though the planet is home to huge sandy deserts like the Sahara, which is about 9 million square kilometers (3.6 million square miles) in size, much of the sand there is useless for industrial purposes. That's because desert sand — smoothed into tiny spheres by the winds — is the wrong shape and size. Only the jagged sand particles found at the bottom of rivers, lakes and in the sea bind well enough to make strong concrete and other products.

Due in part to rapid urbanization and digitization, global demand for sand is increasing. According to UN figures, sand mining has increased more than threefold over the past two decades to over 50 billion metric tons every year.

The US is by far the largest exporter, shipping nearly 6.3 billion tons in 2022. That accounted for around 31.5% of global exports, more than double the export volume of other top exporters like the Netherlands (12.4%), Germany (8.2%) and Belgium (5.9%).

Heightened demand has led to an increase in illegal dredging in places like India, Vietnam and China, where environmental and labor laws aren't always as strict.

But even in approved mines in major export countries like the US, Malaysia, Europe and Canada, digging up all that sand can harm biodiversity and disrupt marine currents and water tables. It can also increase erosion, destroying coastal land and making it more vulnerable to extreme weather. Mining pollutes waterways, while shipping of sand releases carbon emissions, too.

But alternatives to sand mining exist. Glass can be recycled, ground into tiny particles and used in construction and to replenish beaches. And fly ash — the minute bits of ash, dust and soot created by burning fuel — can also be used as a primary binder in concrete, eliminating the need for sand entirely.

When sand is essential, the UN has recommended that it be "extracted and transported in a socially and environmentally sound manner," and that degraded ecosystems are restored with "nature-based solutions."

Edited by: Jennifer Collins

Sources:

World Economic Forum, "Sand mining is close to being an environmental crisis. Here's why — and what can be done about it," September 2023
https://www.weforum.org/agenda/2023/09/global-sand-mining-demand-impacting-environment/

European Climate Adaptation Platform Climate-ADAPT, "Beach and shoreface nourishment," December 2023
https://climate-adapt.eea.europa.eu/en/metadata/adaptation-options/beach-and-shoreface-nourishment

Insel-sylt.de, "Sandaufspülungenauf Sylt" (in German)
https://www.insel-sylt.de/nachhaltigkeit/sandaufspuelung/