a lot of people have got in touch to tell me that in Warsaw, in Poland,

很多人都聯繫過我，說在波蘭的華沙，

the tap water quality is tested and controlled by clams.

自來水水質是由蛤蜊來測試和控制的。

They said that the city constantly runs a sample of its tap water past some mollusks.

他們說，城市會不斷將自來水樣本流經這些軟體動物。

And those are filter feeders, so if there's a contaminant in the water, they will instinctively close.

而蛤蜊是濾食性動物，所以如果水裡有汙染，牠們會本能地關閉外殼。

Sensors attached to them will detect that and raise the alarm.

裝在牠們身上的感測器會偵側到並發出警報。

And I didn't believe it.

我不相信。

It seemed too weird to me.

這對我來說太奇怪了。

And all the articles that I could find about it seemed dodgy, somehow.

而不知為何，我能找到的所有相關文章都看起來很可疑。

They just set off red flags in the research parts of my brain.

這些文章只是讓我腦中的警示信號大響。

There is a very arty Polish documentary about the system,

有一部關於該系統的藝術性波蘭紀錄片，

and a lot of sites repost that film's claims without even mentioning the source,

很多網站都有引用那部電影，有些甚至沒標註來源。

just as a "look at this funny thing off in Poland!"

有點像只是在說「看看這個波蘭的有趣東西！」

It felt like it could be a misinterpreted or mistranslated joke,

這整件事聽起來就像是個誤傳或誤譯的笑話。

or even a deliberate hoax by a filmmaker that got out of control,

或甚至是電影製作人刻意的惡作劇，傳著傳著就失控了。

and that the English speaking world was just believing it because it was quirky and harmless enough.

而英語國家的人就相信了，因為這故事古怪有趣又無害。

There have been plenty of fake things like that spread about in the past, accidentally or otherwise.

過去有很多類似這樣的假消息，不論是不是有人刻意傳播。

Or maybe the clam-sensors did exist, but it was a brief experiment that never went anywhere.

或者，也許蛤蜊感測器真的存在，但只是個從未實行過的短期實驗。

Well, I'm now here in Warsaw, on a famous building in the middle of the river,

我現在正位於華沙，站在河中央著名的建築上，

with a Polish speaking team showing me around.

這邊的波蘭團隊要帶我參觀。

There is a lot of stuff we are not allowed to film here for security reasons.

由於安全原因，這裡很多東西是不允許拍攝的。

Inside here is critical infrastructure.

這裡面，是關鍵的基礎設施。

Plus, it is far too noisy down there for me to talk,

另外，下面太吵，我也不方便說話。

but I'm happy to report that yes, the clams are real.

但很高興地告訴各位，不要懷疑，蛤蜊感測器是真的。

They actually do protect Warsaw,

牠們真的有在保護華沙。

but the story's a little more complicated than that.

但實際情況比表面看起來的更復雜一點。

Warsaw's water source is surface water, the water of the Vistula River.

華沙的水源是地表水，即維斯瓦河河水。

If it turns out that there's ever a toxic substance in the water,

如果發現水中有毒物質，

we must not allow that contaminated water to reach our residents.

我們絕不能讓受污染的水接觸到這裡的居民。

So therefore, we would start a special procedure,

因此，我們會啟動特殊程序，

and our laboratories would carry out a number of tests,

我們的實驗室將進行多項測試，

to find out what is the cause of the water contamination.

以找出造成水污染的原因。

And we would have about two days to do that.

這過程大約需要花上兩天。

The alarm has never sounded yet, but for water safety,

目前警報還沒響起過，但為了水源安全，

an early warning system is very important.

預警系統非常重要。

The important thing is: those clams aren't the only protection.

重點來了，這些蛤蜊並不是唯一的保護措施。

They're not even the main part.

甚至不是主要的部分。

This is still a modern water treatment system,

這仍然是個現代化的水資源處理系統。

with 21st century sensors and detectors to keep everyone safe.

配有 21 世紀的感測及探測器，確保每個人的安全。

This is part of a defense in depth, one part of an early warning system,

這只是深度防禦系統，預警系統的一部分。

one more alarm that can go off,

多一個可以警示的警報。

like an airport that uses explosive sniffing dogs but also electronic detectors.

就像機場會用爆裂物偵測犬，但也會使用電子探測器。

These clams are caught from a very clean lake.

這些蛤蜊是從一個非常乾淨的湖中捕來的。

Then they got to our laboratory where they spend about two weeks acclimatizing.

然後牠們來到我們的實驗室，花大約兩週時間適應環境。

At the same time, although it sound strange, they're also calibrated.

同時，雖然聽起來很奇怪，但它們會經過校準。

What angle of opening is 100% and what is zero?

怎樣的角度是全開，怎樣是完全緊閉？

It's very important that we're able to interpret the result later.

能讓我們後續解讀是非常重要的。

Eight individuals go to this aquarium.

八個蛤蜊會進這個水族館。

And these clams are attached to pedestals to which there's also attached a probe,

這些蛤蜊會附在有探針的基座上，

receiving signals from the sensor that's mounted on the shell of each clam.

安裝在每個蛤蜊殼上的感測器會接收信號。

These sensors are fixed with a special glue, which is absolutely safe for animals.

固定感測器用的是特殊膠水，對動物絕對無害。

Three months later, the clams are returned to their natural habitat.

三個月後，這些蛤蜊會被送回自然棲息地。

We know that this is not a stressful situation for them.

我們知道這對他們來說不是會造成壓力的環境。

We take care of our colleagues here!

我們把我們的同事照顧得很好！

How do we know if there's a problem, if something's happening to the water?

怎麼知道水是否有問題呢？

If, at the same time, six out of eight individuals close their shells for more than four minutes,

如果八個中有六個貝殼同時合上超過四分鐘，

and at the same time, average closing percentage of all the shells falls below 25%.

同時，所有蛤蜊的平均合殼率低於 25%。

We can see that most of these clams are very active now.

我們可以看到現在大部分蛤蜊都很活躍。

The average opening percentage, across all the clams, is 72%.

所有蛤蜊的平均開殼率為 72%。

So, the water is safe.

這表示目前水是安全的。

The technical term for this is "biomonitoring,"

這個技術的專業術語是「生物監測」

and it turns out from more research that this isn't the only place that does it.

而我深入研究後發現，這裡並不是唯一使用此技術的地方。

There are other water companies in Poland that have similar setups,

在波蘭，還有其他水公司也有類似裝置。

plus one in Minnesota, USA, and probably more that I haven't found.

美國明尼蘇達州也有一個，可能還有更多我沒查到的。

At which point I think I can say that: yes, the red flag in my head was wrong.

現在，我想我可以說，沒錯，我腦中的警示信號錯了。

The clams in this building really do help protect Warsaw.

這建築裡的蛤蜊確實有助保護華沙。