Your smart phone is the next water testing kit

Caddisfly is an open source low cost user friendly water testing kit that can be attached to a smart phone’s camera and captured data is transferred to an online map in realtime

There was a time when bulky water testing kits had to be transported to far flung and inaccessible places-villages, forests, rivers, ponds to test the quality of water. Then the results were available after a week or more after the data is analysed in labs. This is changing now. Hi-tech portable easy to carry water testing kits that can be attached to smart phones are in. On 21st July, a prototype of such a kit was released in Bangalore.

In many countries and regions of the world, groundwater and surface water used for drinking is contaminated by toxic chemicals like fluoride, arsenic, nitrate. Millions of people in Bangladesh, India, Vietnam, China use this contaminated water that has led to catastrophic health problems. The water gets contaminated due to a variety of factors including industrial waste, excessive extraction of groundwater and it is a dynamic.


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Today’s fresh water can be contaminated tomorrow. If there is a realtime testing kit, this can fasten mitigation measures and indifferent authorities are forced to take action. In a Huffington Post blog by Amitangshu Acharya, working on issues of water quality, writes that these portable water quality kits can be tools in the hands of citizens and consumers to generate data and build accountability.

So what is this Caddisfly-They are flies that inhabit clean water and hence an indicator of water health. Named after these flies, Caddisfly is also an Open Source Project to develop a low cost water testing kit and they have come up with this intriguing test tube that can be attached to the a smart phone to instantly generate and share water quality data, provided there is good net connectivity. Test results from various locations is shared online enabling communities to evolve locally relevant and sustainable systems for better drinking water. The kit aims to help detect five major contaminants of water-Fluoride, Nitrate, Arsenic, E.Coli and Iron. Data from the instant test shared online is open and can be downloaded.  Technically, Caddisfly is a colorimeter with red, green and blue LEDs flash including a photodiode that measures the intensity of the the light as it passes through sample mixed with reagent.



The kit in its development phase has been tested by Fluoride Knowledge Action Network along with the developers on field like in Jhabua district of Madhya Pradesh, India. As of now, a fully functional prototype for the fluoride test has been lab and field tested.

Being a product in development, there are challenges, some of which have been captured in the Caddisfly blog by developer Samuel Rajkumar who cautions that there are chances that future users will run into trouble trying to get data off Caddisfly and onto phones especially if a wifi or bluetooth is used, which they tried to eliminate by using a smart phone camera, which are highly colour sentive. . This would undermined real time data aggregation. Calibrating may be required for each device individually rather than one calibration for all devices. There are some models on which Caddisfly refuses to work and individual tweaking may be required.

The kit has been developed by a collective of artists, designers and technologists, and was intially developed by Ternup and then partnered with Akvo, who helps people use data, to transform international development.