World Channel


Inventing Tomorrow: Water

As the lakes in her hometown of Bangalore, India fill with clouds of chemical foam that drift through the streets, student Sahithi Pingali creates a “citizen science” project that lets anyone measure and share water quality data, propelling her to the renowned ISEF science fair in Los Angeles.

AIRED: March 20, 2021 | 0:15:41

(traffic rumbles, car horns honking)

(horns honking)

SAHITHI PINGALI: Bangalore was once known

as the City of 1,000 Lakes.

But now it's known as

the Silicon Valley of India,

and now there's only around 93 lakes.

The sad thing is, as more people started moving here,

the lack of infrastructure is definitely a problem.

Where is the lake?

(sucks teeth) Ah!

Oh, my God...

You can't even tell there's a lake.

It's so overgrown with weeds,

um, which is a really bad sign,

because when you have this many weeds,

it's a sign of something called eutrophication,

which is so much nutrient sewage contamination

that all these plants start growing

and they blocked the light to the lower layers of the lake.

Basically just kills everything that lives in the water,

and you have a dead lake.

We went to all the six I normally go to.

The fire and foam

are what really got people interested in the lakes

and got a lot of people to start working on them.

The sewage that causes this foam mainly comes from apartments.

So you can see,

there's a lot of buildings around here,

and they release raw sewage into the lake.

A lot of the detergents and stuff that people use

contain really high levels of phosphates

and all that chemical waste does go untreated.

They say Bangalore will be a dead city in another 25 years

because of water alone.

(bell ringing)

(classroom chatter)

ANNOUNCER (on laptop): Welcome to ISEF, International Science

and Engineering Fair.

How many of you are here

competing for the very first time?

(cheers) Wow!

WOMAN: When the students come

and they've already gone through a series

of competitions to get to the level of ISEF,

and students who really want to advance

know they have to do original research.

This is the science fair

of science fairs.


PINGALI: I started more

on the activism side, but I found it really hard

to get the kind of data I needed regarding

what pollution, exactly, is happening.

Which is why I got into science.

Before ISEF,

I've had to cram a lot of research

into a very little time.

For me ISEF is just the beginning.

I know that would be a great motivator to make sure

I was growing my project.

So I wanted

to mainly achieve two things.

One is make water testing easy.

And, two, make the results accessible to people

and easy to analyze.

So I built my app.

It uses electronic sensors

and chemical test strips

to let you test several parameters of a lake sample.

Here I have some water from... lake.

So I put the probe in the water

and all the values from the probe will be sent

via Bluetooth to my phone.

Okay, so now there's the chemical test strips.

You can see the strip has changed color

so you can use the color recognition part of my app.

Once I've also done the testing with the chemical test strips,

all the data will be on a single form

and that will be sent to the cloud platform.

MAN: When I was growing up, I remember the lake.

It's right... just five minutes walk from our house,

and we would go and jump into the canal and swim.

People sometimes used to wash the clothes.

They used to wash the buffaloes.


If only that was our problem now.

MAN: Everything was connected, right?

This combination of water and sun

is something so sacred to us.

Every aspect of nature--

we pray to the hills, we pray to the water,

we pray to the trees because

these are all giving us everything we need, right?

Yes, we have completely lost our way here.

PINGALI: Sometimes I get that sense of being too small...

a lot.

The lake closest to my house,

even that one lake, to revive it,

would be such a huge task.

But it's a place I really love.

MAN: It's such a relief to come back here.

PINGALI: Yeah, I know, but then because

we live here, it's like we're bubbled, you know?

We don't realize what's going on outside.

I mean, it's our own sewers that goes in it.

People are not realizing.

MAN: Right...

TOUR GUIDE: If you look out the windows

it looks like you'll see Echo Park Lake here.

The lake has actually appeared in movies.

PINGALI: Can we stop and get samples?

ANNOUNCER: Welcome, finalists, to Intel ISEF,

the International Science and Engineering Fair.

Ladies and gentlemen,

Bhanu Prakash.

(cheers and applause)

PRAKASH: When I think about these problems

that are sprinkled everywhere,

the solutions are also sprinkled everywhere.

And that solution lies

in the spark of eyes of people like you.

We have to do everything we can to build an army of scientists

around the world.

That is our only hope.

- What's your project's about?

PINGALI: It's on water monitoring.

- Mm-hmm. PINGALI: Like you can see,

we have these super polluted lakes in Bangalore.

What about you, what's your project on?

Uh, my country, especially my island, have some problems

in the mine industry.

And this season could, uh, you know,

bind the heavy metal elements.

PINGALI: Oh, yeah, like you-- there's all this

heavy metal pollution. - Yeah, yeah.

PINGALI: This pollution, that pollution.

But the problem is in a lot of these water bodies,

we don't know what pollution is there,

so before you can try to mediate it,

you need to find what pollution is there, right?

We could combine our projects, I could detect it,

and you could cure it. - Yeah!


Just go with your passions and start there.

And then you can develop

a project based on what you like.

How do you get this to a point of

how do you build your community?

How do you locally-- - I've been working with

some schools, I've started with students

just because the environmental education...

- Is this your own school?

- Yeah, my own school and a couple nearby.

Have you spoken to some people

in the government or-- - Not the government.

I've spoken to some non-profits,

planning to get to the government eventually.

PRAKASH: Yeah, I think one trick that-- it's counterintuitive

is the more you pass the ownership of this

to other bodies, the more sustainable this will be.

- Yeah. - Because if it's just you,

then you will find it's hard.

Yeah, yeah.

PINGALI: Kids, I think in developing countries,

they get more connected to this environmental issues.

Like, I don't know, I talked to a girl from Ukraine about

trash burning in her country,

and we like bonded a little a bit, "Oh, you guys burn trash?

(laughs) Oh, we burn trash in our country too."

Like we need to solve this together.

- But, I mean, you're like,

like, it's right next to your school?

- Yeah. - But here...

- It would be several miles away.

Like even if you are concerned, you may not even know it exists.

- And that's what I'm saying, in order to be concerned,

you need to know it exists in the first place.

And that's, I think, a main issue in the U.S.

Like, you don't know whether it exists or not.

ANNOUNCER: May I have your attention, please.

Finalists, you must be at your project, ready to be judged

by 8:00 a.m. tomorrow morning.

Okay-- you guys, ask me a question, okay?

Like, you know what kind of questions they ask.

- Yeah. - So ask.

They always ask about the data, it's cool.

They stop you at questions, right?

- Yeah. - You guys just simulate

exactly what they do. - It depends, really.

I mean, you just have to be prepared for it.

Try and interrupt, okay? - Yeah, yeah.

- Because I haven't had practice with interrupting.

Okay, I'll start.

(car horns honking)

ANNOUNCER: Grand floor judges, begin interview period one.

Grand floor judges should begin interview period one.

If you want, I can give you a quick demo of how it works.

- Well, what were the parameters you were focusing on?

PINGALI: Conductivity, total dissolved solids,

dissolved oxygen,

nitrates, nitrites, phosphates, iron, copper,

total hardness, total alkalinity and a few others.

I found that data talks so much.

You can say, "This lake stinks, this lake is terrible,

this lake is polluted," everyone ignores you.

But when you say, "Look at this chart,

"I can show you that because this lake

"got this amount of pollution, the groundwater next to it

"got this amount pollution.

And this is the relation to the malaria cases in the area."

When you have that kind of data,

it really makes a difference. and it makes people

listen to you, which is why I really got excited by this,

because now I'm actually collecting that kind of data

that I can use in that way.

And I think that's something

that really helps make a difference.

- That sounds exciting. Thanks for being here.

- Thank you. - Bye.

ANNOUNCER: This ends period 19.

Judges, all of your scores should now be recorded.

So, yeah. (chuckles)

- Bye. - Bye.

(chattering) - Thanks...

How do I eat this?

Is this a soft taco?

Can I just eat it like roti?

MAN: Come on over here!

(cheers and applause)

ANNOUNCER: Ladies and gentlemen, welcome to the awards ceremony.

There are multiple winners

in each of the 22 categories.

(cheers and applause)

In the category of animal sciences...

(cheers and applause)

In the category

of translational medical science...

In the category of earth and environmental sciences...

from Bengaluru, Karnataka, India,

Sahithi Pingali. (cheers and applause)

(cheers and applause)


- Congratulations! - Thank you.

I'm very proud of you. - Great job.

- You did a wonderful job.

So proud of you... keep it up.

- Sahithi, congratulation! (laughs)

PINGALI: After ISEF, I started a two-month internship

here at the University of Michigan.

I felt that I needed

new resources and new people and advice.

So this isn't something

I want to drop when I go back to Bangalore in two weeks,

I definitely want to continue,

and hopefully this list will grow.


I'm blown away by the fact that you're still

at, like, high school.

It's amazing, like,

but I just wonder, how are you going to control

for the potential of the public doing the tests incorrectly?

So, yeah, we're working one step at a time,

but my thing was more of sitting

and coding and doing experiments.

But now that you have to handle publicizing and the scaling,

it's a whole other game.

This is a full time job, Sahithi,

how are you going to manage this?


PINGALI: At the science fair,

there was one that keeps coming back to me,

you can't do it alone.

You need to collaborate with others so it can grow.

With science, there's, there's really no value in

just creating this data and creating these inventions

and just sitting on them.

You do need to actually have them

make a difference in the world.


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