Project Duration: 4 months | 2016


TDU (Trans Disciplinary University) was our client for this project. They had been working towards a low cost solution by evolving traditional solutions like using copper and herbs to purify water for the under-served population. They had been able to show a vast decline of the microbial content in the water using their copper coil but they needed our help to further redesign the device to make it more effective, efficient, acceptable and affordable which could really save lives.

My focus was on creating a device which would fit in the daily cycle of my target audience without exhausting another resource. The device should be multi purpose, low maintenance and able to generate safe drinking water.



  • Kills diarrhoea pathogens.

  • The copper leaching of this device is between 220-400 ppb.

  • WHO permeable copper leaching for safe drinking water is 2000ppb.

  • 16 hour contact area. By increasing the surface area of the copper, the time can be minimized.

  • By increasing the temperature to 35 degree celsius, ionisation happens faster.

  • By rotation also, the ionisation happens faster. 150 RPM.

  • Citric acid powder is used to clean the copper coil


Possible diametre of the chord: 3mm, 6mm, 8mm, 10mm.

Calculating the length in each case:


Pie x L= 912 cm2
= 912/ 3.14 x 1
= 290.4 cm

8mm= 0.8cm:

Pie x L= 912 cm2
= 912/ 3.14 x 0.8
= 363.0 cm

6mm= 0.6cm:

Pie x L= 912 cm2
= 912/ 3.14 x 0.6
= 484.0 cm


Pie x L= 912 cm2
= 912/ 3.14 x 0.3
= 859.1 cm





The secondary research started with studying about different metals and their current and historical use. From gold being used in jewelry to it's use in surgeries and stabilizing body temperature.

Berkey bottle


Tata Swach

Lifestraw family

Apart from understanding the basic properties of the additional materials, it was important to understand the current market. In order to design a simple purifying machine, I wanted to understand what already existed. How are other companies or people are trying to solve a similar problem.

The products also reflect the lifestyle of the target audience, the demands of that segment, the challenges they face when it comes drinking water.


Ramanagara has a population of 79,365 | 13% of the population is under 6 years of age.
The river is heavily polluted by the dispersion of toxic waste by the manufacturing units in the area.



- What chemicals and pathogens were found in the recent water samples?

- What herbs have you tested with? What data was received?

- What is the heavy metals does it purify, if any?

-What chemicals causes the foam in the water ?

-Why the shape of the apparatus is a coil ?

-What was the change in data due to stirring and heating?

-Weren't you supposed to test the water within two hours of collecting it?

-Where do you get your copper from, how much does it cost/kg?

-Where do you get the production done?

-How much high concentrated copper ionized water would be required for 100 litres of water?

-In Karnataka, what are the general contaminants found?

- What is the ratio of heat to time reduction?

-Have you worked with solar panels, if yes, what were the results and cost?

-We found that drinkable water is free of particles, pathogens and have low level of chemicals, have you tried battling all these categories?

-Do you have any method of calculating the toxic contents that we as students could use to test our ideas ?

-Will heating of copper increase the ion release? will it have negative effect?

- Have you experimented with any other shape of copper besides the coil?

-What is the maximum ratio of copper surface area to water without crossing the ppb limit? 


-How many people are there in your family?

-If you have children in the family, what age group?

-What is your profession?

-What’s your schedule like?

-What’s the water source?

-Where and how do you store your water?

-Is the water availability regular?

-If and how much do you pay monthly for the water?

-Do you think the water is clean?

-What is the average consumption of water in your family?

-Do you purify your water, if yes how?

-What do you think your grandmother did to purify water and how do you it was different?

-Are you aware of any of the traditional practices?


-Do you own any copper vessels? If yes.

-Why do you think people used to store water in copper utensils?

-What do you think is the rate of copper in your town?

-How do you determine the purity of the metal?

-What kind of material do you use and why?  what are the rates and lifespan ?

-If in past, anyone from your family have had a disease?

-Do you know of any water borne diseases?

-Have you heard of diarrhea, if yes, how and why.

-How do you access the water stored in your pots.

-How much water do you use while cooking?

-What is the common rate of water?

-What is the season in the area like?

-Is there enough rainfall, if yes, do you do any rainwater harvesting?

-Where do you get groceries? If known, what is the source to the water for farming?

-Do you have any rules in your village regarding water?

-Are there any sanitation facilities available?



Currently the copper coil purification is only being adapted in families having children below 6 of age.

There was no alternate in school, so the children are just limited to the amount of water they carry from home.

Even after purifying the water from copper, people carried the water in PET bottles throught the day in exposed sunlight. What happens to the plastic leaching?

Handling of containers.

In many cases, even after seeing the water visibly water contaminated, people chose to drink from that rather travelling few Kms for Tata purifed water.

The older generation still believed the diseases were god given and water contamination had very minimal role in that.

Lack of action. Even after witnessing the exploitation first hand by the infamous industries, people were grateful for purification plants installed in the act of misleading by the very same companies.

The amount of electricity utilised for purification.


There’s still a notion existing that diseases are god given, hence lifting the burden from the water pollution.


For deciding the target audience, I visited various communities in and around Yelahanka. The community is decided upon could be classified as D1 and D2. All of them were daily wage earners like the vegetable vendors, the auto drivers, the laborers and the painters. Their source for water was a common bore-well with water availability for 4 hours (6AM - 12PM). They had proper electricity connection, but during power cuts, their only option are the other bore-wells nearby.

Their day begins with them fetching water and storing it in huge plastic containers. The water  from the borewell is used for all purposes; for household chores, bathing and for drinking. Although the drinking water is stored separately inside the house.

Despite of being settled in an urban space. they missed the traditionality in their lifestyle, like using terracotta to store their water in. Despite of having gas, they prefer to cook food and especially boil water on firewood because they love the certain essence it adds to the taste. Taste was a major factor both in terms of cooking on firewood or using terracotta.

When asked about copper and traditional ways of purification, they use boiling of water in case of someone being sick in the house and for visible particles in the water, they pour it through a cloth piece. They also believe that  terracotta has the property to purify their water.


I didn't want to exhaust another resource while purifying water. For solving one problem, I don't want to create another problem for them.

Since the purification takes about 10-12 hours without using additional resources. After observing their lifestyle, purification through night seemed fit and also because they don't lead lead a very fast lifestyle, overnight purification seemed convenient for them.

Inspired by the water system in Europe, I initially wanted to make a community purification system. After observing their lifestyle, the majority of microbial contamination occurs during handling  of water.  While pouring and carrying water, hands are constantly dipped in the containers, hence, contaminating.

Since there people live on a disposable income, cost is a major factor for them.

Thinking from their point of view. Why would they invest in something as basic as copper but claims to purify water. So I wanted my device to be multi purpose, that I does something else also apart from purifying water through the properties of copper.

Initially I thought of using heat to fasten the process but 



This usage module is to show how both the devices fits in their daily cycle. In both cases, the purification happens overnight. The person would fill water at 6PM to get clean drinking water in the morning and for the whole of next day.

There is no additional resource being used. 


Target audiences take on the designs; the lota seemed to simple to purify water. They preferred the sieve because it came with a container which reminded them of the other purifiers in the market.

Their one concern was electricity but after being informed that the purification would not require another resource, they seemed happy.

When talking about different purifiers in the market and electricity, they could only relate to the one with Hema Mailini. On mentioning the cost, some said that they would rather prefer to go to a doctor when sick.

This led to few questions like:
Why would they want to buy this device? What was the selling point? Would it be wise to tell them that their water is contaminated, the same water that comes from the very auspicious Kavery river or the ground? Would they believe that something as simple as a lota can purify their water? What proof can be given to them?

Volume: 15l

Circumference= 2pie x r
2 x 22/7 x r= 33 (the circumference of the bisleri can)
r= 21/4= 5.25 in
5.25 x 2.5= 13.12 cm

Area= pie x r x r
= 22/7 x 5.25 x 5.25
= 86.54 in2

86.54in2 = 558cm2

Surface Area without calculation the volume:
540.50 + 540.50 = 1080

Amount of copper needed:
91.2 x 15l = 1,368cm2

Radius of the holes= 1mm
22/7 x1 x1 = 3.14mm

3.14mm = 0.314cm

Estimated number of holes= 200
0.31 x 200 = 62

surface area left:
1080 - (62=62) =956cm

Defictit of copper:
1,368- 956 = 412cm


Height of the container:
15000= pie x d2/4 x h
15000x 4= 3.14x 676x h
h= 29.57cm

Area of a circle= pie x r x r
= 3.14 x 10.5 x 10.5

Total copper exposed= 346 +346= 692

Area of the inner circle= 3.14 x 6 x 6
=3.14 x 12
= 37.68
37.68+ 37.68 = 74

Copper till now= 692-74= 618
Copper required= 1368
More copper required= 1368-618= 750

Outer surface area of one mesh:
Length say 12cm
Radius+ 0.5mm

=2x 3.14x r x h
2x 3.14 x 120 x 0.5
=37.6 cm2

Number of mesh require for the inner circle

=120/2 x 2= 120

Amount of Copper in the inner circle with mesh:
=12x 37.6
=451.2 cm2

Which means this is Do-able!

After observing the lifestyle of the target audience and as someone who believes in sustainability. I didn't want to expose them to more usage of plastic. Apart from being non- biodegradable, there’s also a risk of plastic leaching.

Through the interviews conducted, people miss drinking from a terracotta pot. It’s an old classic design so deeply integrated in our lifestyle and so it has a huge degree of trust as well. This would also eliminate the reliance on huge industries and instead could retain the traditional aspect along with generating employment opportunities for people within the community.

-Terracotta is a fragile material and As the device would be placed inside the container, the terracotta pot has defined dimensions. So, in case of any breakage, the user has no option but to buy another pot from the same distributor otherwise the device would become useless. so it increases the degree of reliance.

-It would hard to find a potter in each community, and so the cost of transporting the terracotta pot to distant places would add up the cost. 


The final design is of a copper plate with a sieve in the middle with a proper calculated proof on the amount of copper.  

The plate sits on the depth of 5l and a height of 10l to avoid ionization in concentrated water.

The sieve provides a visual satisfaction on purifying the visible particles and the depth of the sieve creates an additional space for the herbs to sit on. The herbs improve the taste of the water, helps in purification as well and adds to the satisfaction of the us


Stainless steel was another proposed material after the feedbacks on the terracotta container.

Stainless steel is durable, keeps the water cool and most importantly it gives a certain level of status over a plastic container.

The transportation of stainless steel is also simple, the cost would slightly vary over a plastic container.

Of all the three materials proposed, terracotta has a higher hand in terms of the initial  investment for production. Both steel and Plastic containers would require production of a mould, which is very expensive.

Documentation book for The Water Project