All of Singapore's trash ends up on this island, and it doesn't look like a dump

How exactly do they manage that?

Singapore has a population of about 5.61 million, and each person throws out about 0.86 kilograms of trash a day. Once it has been processed, all of it is shipped out to a landfill at sea.

South of Singapore lie two small islands, Pulau Sakeng and Pulau Semakau. Between them they enclose a landfill covering 3.5 square kilometers with a capacity of 63 million cubic meters: the Semakau Landfill.

Semakau takes the ash from every waste incineration plant in Singapore, along with non-recyclable household waste and industrial and construction debris. But there is no sharp stench. Walk the causeway here and you'll see seabirds passing overhead. On the other side of the landfill area, fishing boats are still working.

Singapore is not the first country to handle its trash by reclaiming land. Staten Island in New York was once the world's largest landfill; it closed in 2001 and is being turned into a park, with the work due to finish in 2035. Japan, too, compresses and detoxifies non-combustible waste and uses it as fill to reclaim land. Odaiba, an entertainment district in Tokyo, is half built on land filled in with trash.

What is different about Semakau is that the island buries trash and restores its ecology at the same time, and it is open to visitors. On weekdays, though not weekends, Semakau takes visitors who want to see the facilities and the ecology for themselves. Most of them come from environmental research organizations, or are ecologists or students, but the island has drawn other visitors too. In 2007, one couple chose to shoot their wedding photos here.

This year's Singapore Clean Environment Summit offered a chance to visit, and we went to take a look at the island ourselves.

The place that takes all of Singapore's trash was once a fishing island with 780 residents

From Marina Bay, Singapore's commercial center, it is a half-hour bus ride south to a pier, then another half hour by boat, about 8 kilometers further south, to reach Semakau.

In the 1960s and 1970s, Singapore dealt with its trash by dumping it along the coast, untreated. Residents nearby complained bitterly about the pollution. The government later ruled that waste had to be sorted and incinerated before it was buried. The resulting ash and non-recyclable waste went to two landfills: Lim Chu Kang in the north of the country and Lorong Halus in Tampines.

By 1989, Singapore was producing 1.9 million tonnes of waste a year. The government expected that figure to reach 2.3 million tonnes by 2000, by which point the two Tampines landfills would be full. No other suitable landfill site could be found on the main island, so the government decided to wall off a stretch of water between Pulau Sakeng and Pulau Semakau and develop the two islands together.

Records show that before development, most islanders here were fishermen, and Semakau was the main settlement in the area. In 1955 it had only 780 residents; as petrochemical industry arrived, the population grew to 1,600 by 1969. The island had a school, a community center, a mosque and a football field.

In 1975, the government decided to turn Semakau into an integrated petrochemical industrial park and drew up a land reclamation plan costing S$150 million. From 1977, islanders were gradually resettled on mainland Singapore, but the industrial park was shelved. Only in 1989, when the new Minister for the Environment, Ahmad Mattar, took office, did the idea of burying trash on an offshore island come up.

In 1994, the government approved the proposal and began developing the shoals and seabed east of Semakau, at an estimated cost of S$1.36 billion.

Because Pulau Sakeng and Semakau were small to begin with, the government enlarged them fivefold by filling, and built a seawall about 8.15 kilometers long. The seawall is piled up from sand, gravel, rock and earth, and to seal in pollution, its outer face is cast with an impermeable polyethylene membrane.

In 1999, as the two Tampines landfills closed one after the other, the Semakau Landfill began operating. It was expected to last 30 years, but as recycling rates rose year after year, its projected life was extended by another 15.

Semakau was planned in two phases of roughly equal size. Phase one, in the south of the island, was divided into 11 landfill cells; to use the space fully and make dumping easier, each cell is walled off from the next by sand-and-gravel bunds. Local staff say all 11 are now nearly full — walk the causeway past the finished cells and you can see bare, untreated black ash and fill.

Reclaiming one square kilometer of sea takes 70 million tonnes of sand and rock. According to Singapore's National Environment Agency (NEA), phase one of Semakau cost S$610 million, most of it for sand and rock.

Singapore has four working incineration plants, which burn nearly 6,900 tonnes of trash a day and leave 1,600 tonnes of ash. Add 400 tonnes of waste that can be neither recycled nor burned, and 2,000 tonnes of trash goes each day by truck to the Tuas Marine Transfer Station, near the Tuas incineration plant in the west of the country, where it is weighed before being shipped to Semakau.

Each shipment is a barge pulled by a tugboat. The barge holds the trash and carries covers cut to its length, so that nothing blows into the surrounding waters on the way. The Tuas Marine Transfer Station is 33.3 kilometers from Semakau, a three-hour trip.

To stay out of the way of shipping in the area, the tugboats move the trash at night and it is dumped during the day. At both ends, large excavators fitted with specially designed grabs help shift the waste; each truck carries a payload of around 35 tonnes.

Trucks drive the trash out onto the causeway and tip it in. Because the causeway is built only of sand and rock, the ground can give way as a truck tips, and there have been accidents in which an entire truck, worker included, slid into the landfill.

Work on phase two, in the north, began in 2015. With sand and rock prices climbing and countries that had long supplied Singapore banning the sand trade, the new Minister for the Environment decided not to divide phase two into cells at all, to save on sand and rock. This phase cost only S$37 million to build.

For phase two, the government also borrowed equipment the Japanese use in land reclamation, building a floating platform about 200 meters long with a long arm on the causeway to help the dump trucks unload. There have been no more dumping accidents since.

The bund between Semakau and Pulau Sakeng also has a gap fitted with water pipes, open to the sea around it, so that seawater keeps circulating.

Incineration cuts trash to 20% of its weight and 10% of its volume. Singapore now recycles 60% of its waste each year; another 38% is burned to generate electricity, and the remaining 2% goes straight to the landfill. The four incineration plants supply 2% to 3% of the country's electricity.

Semakau also has a floating wastewater treatment plant. It cleans the excess water that rain leaves in the landfill area, and once it meets discharge standards, releases it into the sea on the other side.

Burying trash and protecting the ecology at the same time

Once a stretch of Semakau is full, it is covered with fresh soil and planted with trees, grass, or fruit and vegetables that will survive there. The government's idea is that when every usable part of the island is full, Semakau will be a small natural island of rolling hills rather than an abandoned dump.

Some records say the name Semakau may come from the Malay word "bakau," meaning mangrove — the hardiest vegetation here.

Phase one destroyed 130,000 square meters of mangroves on Semakau. The government replanted them, and they have grown back into a small forest. The mangroves double as a living indicator for the landfill: how well they grow tells staff whether toxins are leaking out of the buried areas.

Along the landfill there is a water-quality monitoring well every 100 to 200 meters, each more than 30 meters deep. Twice a month, staff test the water in the areas already filled.

To protect the island's marine life as far as possible, the government moved the coral colonies inside and near the enclosed area elsewhere. Between September 2014 and January 2015, more than 700 colonies were transplanted to the Sisters' Islands.

A small marine park has also been set aside in the southeast of Semakau, for visiting and observation, and you can walk to it along the path on the causeway. It holds the kinds of marine life found on the other islands nearby: crabs, starfish, sea spiders, coral.

Not far from the Semakau pier there is a visitor center with a restaurant, where tourists can look around and rest. There are pavilions along the causeway, and besides the seabirds, on the northern stretch you can watch lizards sunning themselves.

Semakau has none of the beach swimming areas, restaurants and hotels of Sentosa or the Sisters' Islands, but these measures at least make it less unpleasant than other landfills.

By NEA's count, after Semakau opened to the general public in July 2005, visitor numbers more than tripled over the next five years, from 4,000 to 13,000 by 2010.

In recent years Semakau has also been zoned as a new-energy demonstration area. Singapore's first large offshore grid system is being trialed here, combining solar, wind, tidal and natural gas power to run the island's daily operations on zero-carbon electricity. Once the technology is ready, the system will be used on other islands or in remote villages.

But the island will only last until 2035

Protecting the ecology makes a trash island's present and future look less grim, but landfill space is finite, and Semakau carries risks no one can measure yet.

Mention the Semakau landfill to people who live in Singapore and they say, with a shrug, that the country has no choice. Everyone here knows how precious land is in Singapore, and they know just as well that its future is uncertain.

In Tolstoy's short story How Much Land Does a Man Need? there is a moment when a disheartened peasant thinks to himself: "Our only trouble is that we haven't land enough. If I had plenty of land, I shouldn't fear the Devil himself."

These are the problems Singapore faces, and its answer comes down to the three Rs, meant to stretch the life of the Semakau landfill as far as it will go: Reduce, Reuse and Recycle. Supermarkets ask shoppers to bring their own reusable bags, and dedicated food-waste plants turn the leftovers from food courts into biogas or organic fertilizer.

Not everyone agrees that burning trash is good for the environment. Opponents point out that incineration releases mercury, dioxins and volatile organic compounds into the air. Dioxins cause cancer, and incineration is their main source.

Malaysia and Indonesia have both seen public protests against government incineration, aimed at stopping plans for new incinerators. The Philippines banned the burning of municipal, medical and hazardous waste as early as 1999, in its Clean Air Act.

Buried trash is unlikely to leak into the surrounding waters and pollute them, but the risk is real. Scott Kaufman, an associate professor at Columbia University, says the safeguards can keep waste from escaping for decades, but as the geology shifts they will eventually fail, leaving the danger to later generations.

Asked what happens once the current landfill area is full, staff here would say only that it depends on the government's urban plan for the next five or ten years.

One thing can be predicted: the amount of waste Singapore has to handle keeps rising every year. By 2017 it had reached 75 million tonnes a year, nearly four times the figure when Semakau opened.

The NEA also forecasts that Singapore will need a new incinerator costing several million US dollars every five to seven years, and a new landfill like Semakau every 25 to 30 years.

And in Singapore, most of the small islands have already been developed into tourist islands. It would be hard to find another offshore island as thinly populated, as isolated and as undeveloped as Semakau once was.

Cover image: blogspot

Unlabeled images in this article were taken by the author.