Have you ever wondered what happens to your poop when you use the bathroom on a train or airplane?
Well, apparently the administrators in China chose to avoid speculating on this question, too. And it’s leading to a serious plumbing problem.
After testing waste water quality at a high-speed rail station in Beijing, researchers in China have discovered that levels of human waste were hundreds, even thousands, of times higher than what’s normally found in the city’s waste system.
Now, how did this happen?
Sealed toilets.
According to Xin Siyuan, the head of the research team, “The waste water from sealed toilets on trains has a higher content of suspended solids, organic matter (COD), nitrogen, and phosphorus than general domestic waste water.
With the increase of the amount of waste water from sealed toilets, the existing sewage treatment facilities can no longer meet the current urban network discharge standards, and it is urgent to establish more complete waste water treatment facilities.”
Why is this a problem? Because there’s a lot of high-speed rail in China. And that means a whole lot of poop.
In fact, there’s enough high-speed rail in China to circle the planet. Around 26,000 miles, in fact. It’s now the most popular means of travel, with some lines carrying as many as 200 million people a year.
And these trains have nice bathrooms. Automatic doors. Clean seats. They’re even spacious.
So this is no small poo problem.
Here’s how waste works on a train:
It collects in a tank, and when the tank gets full, its pumped out for treatment at a local facility often right in the train station.
But when these facilities were built, nobody expected there to be hundreds of millions of people using these stations all the time.
Believe it or not, this isn’t a new problem. Indian Railways has been decried as an “open toilet” for years (ok, maybe believe it), with people dumping poop right on the tracks.
They handled this problem by equipping their trains with bio-toilets that break the waste down, but this fix won’t work for the high-speed rail trains in China.
Why? Because they move too fast. There’s just too much poo and not enough time for the microbes to break it down.
At the same time, the local facilities meant to handle all this crap are breaking down under the load. And if they buckle and excess waste ends up in the sewage system, it can poison local life and become a petri dish for disease.
All is Not Lost
But Xin and his team are on the job. They’re testing new microorganisms that can quickly break down nitrogen and other problematic chemicals in water much faster than before.
They’re also testing new methods for collection, including plastic sheets. In combination, they say that could remove up to 95 percent of the chemicals involved. T
here are also all-in-one devices being developed that can take over some of the burden from local treatment plants.
You can learn more about the problem and their fascinating solutions here.
It’s all a healthy reminder to keep essential facilities in mind when you build something new.
Neil