Cultivating A Wastewater Treatment System

Sep 16, 2011
Originally published on September 16, 2011 1:55 pm
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IRA FLATOW, host: Up next: Flora Lichtman's here with our Video Pick of the Week. Hi, Flora.


FLATOW: And we're into an alternative fuel mode. You've got some alternative something else there.


LICHTMAN: Yes. Actually, it has a biofuel component, but it's really mostly about my favorite beat, which is wastewater processing and remediation.

FLATOW: Is that - it's your favorite.


LICHTMAN: I think it's becoming my favorite.

FLATOW: It was mine at one point.

LICHTMAN: I'm really interested in it right now.

FLATOW: I almost went to graduate school on wastewater engineering, because I thought it was really fascinating.

LICHTMAN: It is. And there are all these different types of solutions. So the one that we looked at in this video this week was - it's in Rockaway, Queens, in New York. And the New York City Department of Environmental Protection has installed this sort of prototype system where they're using pond scum to purify water, basically.

FLATOW: Pond scum. That'd be...

LICHTMAN: I'll be more specific for - I know our listeners will want to know exactly: so, green algae.

FLATOW: Green algae. Why didn't you just say so?

LICHTMAN: Yeah, right. Exactly.


LICHTMAN: So there's this filament - basically, the way it looks is that there are these two long ramps. They're kind of like little slides, and they're 350 feet long, and it's all flowing downhill. And they take this water from the sewage treatment plant across the street, pump it over to these slides and let it go down this bed of mesh. And then algae sort of naturally grows, and then the algae seems to remediate the water in some ways.

So basically, the algae takes out phosphorous and nitrogen and uses it to grow. And then, also, the dissolved oxygen content goes up a lot as it goes down this little chute. So - and then the water gets pumped, sort of chlorinated, and then pumped back into Jamaica Bay. So this is a little - a very tiny, you know...

FLATOW: Sort of demonstration project.

LICHTMAN: It is a demonstration project, for sure. I mean, that was the thing. New York is such a - everything in New York is so big. I was surprised. But it is neat, because they're actually harvesting the algae for biofuel.

FLATOW: Yeah. And, you know, it's interesting, as you look at your video - it's up on our Video Pick of the Week site up there on our website at And it's a 300-foot, what I'd call a rain gutter, right?


FLATOW: Something like that.

LICHTMAN: It's a little low-tech. OK.


FLATOW: But it's long, and there's water flowing down. There's algae growing in it, right?

LICHTMAN: As the DEP person who we spoke with said: Gravity works. What can I say?

FLATOW: Make the best use out of it. And they're very - and this is a serious project, to see, you know, as I was saying, I know aquarists - if you have an aquarium at home and you have something called a refugium - you'll know what I'm talking about if you know what I'm talking about - where you clean the water, and they have algae in it. Yeah.

LICHTMAN: Yeah. It's the same concept. And I think then the other thing that is neat is they're trying to maximize algae growth, and they actually have these little squeegees to harvest the algae, because they're hoping that it could be used for something else.

So they made their first little test bottle of biobutanol from this algae, which, you know, it's not - they have one bottle so far. So it's not going to run the plant yet, but that's the idea. Maybe you can turn this wastewater into something useful.

FLATOW: Well, you can make - you make a decision for yourself by going over to our website at That's Flora's Video Pick of the Week. Thank you, Flora.

LICHTMAN: Thanks, Ira.

FLATOW: And Flora and I will be out at the Maker Faire this week. Come see us.


FLATOW: I'll be there tomorrow. Flora will be there on Sunday.


FLATOW: We have a - SCIENCE FRIDAY has a booth at the Maker Faire at the New York Hall of Science out there in Queens. So we want to see you all there. Come and drop by our booth.

LICHTMAN: Say hello.

FLATOW: Say hello, and maybe you'll get a little prize or something out there for dropping by. That's about all the time we have for this week. Transcript provided by NPR, Copyright NPR.