On a bend in the Thames, beyond the Millennium Dome and heading east from Thamesmead, past new developments and tidy houses, sits one of the largest sewage works in Europe. Despite its size, it's quite tricky to find, though there are helpful brown signs stuck on lamp posts along the highway providing directions to Crossness Engines. The engines are a tourist attraction, but only for a select few: The majority of Londoners—and most city dwellers—prefer not to think about where the waste ends up once the flush has been pulled.
Crossness Pumping Station has been on this site since 1865. It's open to the public a couple of times a month, though the pumps no longer operate. Built by the great sewer designer Joseph Bazalgette, who arranged for the pumps to slosh London's sewage into the river once a day, the engines and pumping house are now run by the Crossness Engines Trust, chaired by the great man's descendant, TV producer and Big Brother creator Peter Bazalgette. The trust rescued the dilapidated buildings in 1985 and has spruced up the spectacular ironwork and splendid engines. They can arrange for the pumps to operate for visitors, but otherwise Bazalgette's brilliant creations have been silent since the 1920s, when someone noticed that all that sewage was killing the river.
After that, the waste was taken in barges and dumped at sea, until the enlightened noticed that the sea was suffering, too. It wasn't until 1997 that this practice was stopped (though around the world, it's still how 95 percent of sewage is disposed of), and the East London Sludge Incinerator was built. I'm more interested in ELSI than in the engines. The pump house gets the tourists, but ELSI is also magnificent, its wavelike silver roof soaring over the 400 acres of land, dozens of gritters, sedimentation tanks, and hurtling sewage flows. Bazalgette's engines may fascinate, but the mystery of how 2.2 million people's waste is disposed of is more to my liking.
Thames Water, which runs Crossness, used to allow members of the public to visit the working site (not just the engines), until a health and safety risk assessment stopped the practice. But I've been granted a tour with Brian Phelps, the Crossness Operation Production Manager and the man who used to run ELSI. He's still proprietarily proud of her and of Crossness as a whole. And why not, when this quiet, un-smelly place turns human waste, debris, and anything else that ends up in sewers or drains into cleaned liquid effluent and sludge burned by ELSI. The ash gets buried in landfill, which isn't ideal, and ELSI's capacity is less than they'd hoped—110 tons a day instead of 168—but she saves on energy bills, as heat in the incinerator is turned into steam and then into 3 to 4 megawatts of electricity—half of what Crossness needs to run.
The tour begins at the fine-screening plant. This is the first filter for the sewage flow arriving through a huge outfall sewer hidden under a green embankment. The mesh screens remove plastics and large debris, though pesky Q-tips always get through. This is where, in the last six months, Crossness workers have been noticing increasing amounts of hospital waste. "We've found bandages, dressings, syringes. Even green hospital aprons." It's a mystery, says Phelps. Perhaps hospitals have stopped incinerating their clinical waste and turned instead to chucking it down the drain. But as with nearly all the waste that people choose to put into the sewage system, Thames Water has little chance of tracing it and prosecuting the culprits. They just deal with it.
The tour continues past the primary sedimentation tanks, past the storm drains that hold excess rainwater in summer storms, past the aeration tanks where the water is being agitated by machinery to create the oxygen that microorganisms need to survive so they can munch at—and purify—the organic matter in sewage. It all looks mighty complicated, with plenty of tripping hazards, though Phelps says the only casualty he knows of was a young boy who fell down a manhole, was swept down the sewer, and retrieved from the screening section. Apparently, it's less complicated than it seems. "Guess how many staff it takes to operate this?" asks Phelps. I shrug. A dozen? Two dozen? "Two." One to operate the computers that run everything and another to walk around the site and check that the computers are running everything. Telemetry and other clever software means that the basest of human products is dealt with by the cleverest of human ingenuity. But it can still be done manually. Before the millennium, Thames Water developed contingency plans in case of system failure. "The site could be run manually by four staff, probably," says Phelps. "All you're controlling is the number of pumps."
But things don't always run smoothly. Sewage works that serve big cities run into trouble when the cities grow up around them. The residents of Belvedere, which abuts Crossness, have fought several battles over the incinerator and over the smell. The site smells fine the day I visit, but several court cases show that's not always true. In 2004, the local council took Crossness to court over "odor nuisance." Residents testified that the smell made them sick, that they had to have multiple fans running in their homes because they couldn't open the windows, that they were embarrassed to have guests in their houses. Thames Water was served with an odor-abatement order, though it pleaded special circumstances: The glamorous, glittering ELSI wasn't performing as expected. The sludge it was supposed to burn was arriving wetter than planned, and the special high-tech panels that should have squeezed it dry were getting overloaded. The excess sludge had to be stored on-site, some of it in open tanks. It stank.
Things are better now, says Phelps, as we sit in view of the incinerator and a green tarp structure nearby. This houses—temporarily—the liming process, which turns excess sludge into sludge cake, which is then given away free to farmers.
It's an expensive process for Thames Water, but it causes less odor, and it bothers residents less. Phelps is sympathetic to complaints about bad smells, up to a point: "By its nature, sewage smells. Unless we cover the whole site in a bubble, it will smell." Residents may resent the fact that their borough deals with the waste of dozens of other London boroughs. "But it's been here since 1865. Anyway, it's not always us that's at fault. When we get a complaint, we check the wind direction and the location of the complaint, and sometimes it physically can't be us. But we usually get the blame." Phelps has braved the lion's den of residents' meetings a couple of times, but he thinks Thames Water could do more, such as publicizing the Crossness nature reserve located behind the site, which the company set up as a condition of building the incinerator. Now it houses water voles, marsh birds, all sorts of flora and fauna, but "we should promote it more. People don't know." At social occasions, when he tells people what he does, most ask questions. "The most common one is, 'Does it smell?' But some people literally step backward."
Soon, though, more people will be unavoidably confronted with Crossness. There'll be no stepping backward, because the nearby river banks will hold the 120,000 houses and apartments promised by the Labor government to solve London's housing problem. Already, says Phelps with resignation, "People flush loos and don't think anything of it." More loos will bring more waste. No one at Crossness expects it to bring more understanding.
Rose George is the author of The Big Necessity: The Unmentionable World of Human Waste and Why it Matters.