DIY Water Quality Workshop

via the Public Lab

image via The Public Lab

In this workshop, we wanted to give students a hands-on, visceral sense of water quality, using audio output as a more accessible way of comparing the water they’d sampled from different locations near to their home.  We also wanted to see if this sort of activity would generate water quality data that is useful for community water monitoring projects.

What do individual participants get out of the activity?
We hoped that they were able to engage with water quality in a more accessible way, so that it didn’t seem as mysterious or technical to them.  We did this by making a connection between dissolved solids in water and table salt.  We also had them construct the sensors they were using, to make the technology seem more approachable. 
What You Need For This Activity
Who can participate?:
Ages 6+.
Individuals, or groups of 1 to 3 can participate.
The participants follow a wiring diagram that seems to be fairly straightforward for ages 6+, so requires no special skills.
What resources are necessary?
There is about $20 of electronics (available from most electronics stores) required for the activity; a small amount of table space / desk are required for each setup.  Also: water, and salt.
What kind of mentors/facilitators with what skills does it require?  
– It’s easier for participants to build  the devices when someone who has a basic background in electronics is present; but this isn’t strictly necessary; the step-by-step instructions (akin to an ‘instructable’) are sufficient for most participants to construct the device. 
– A basic introduction to conductivity in water, its relationship to dissolved solids and temperature, and the connection between these parameters and water quality, is a helpful discussion for participants to have.  Most facilitators can provide this after reading through the accompanying background material.
How long does it take?
– Assembling the devices takes about 1 to 1.5 hours.  
– A typical activity involves collecting water samples from various locations, bringing them back to a meeting location, and allowing them to equilibrate in temperature overnight.  
– Then, in a follow-up meeting, the water samples are compared against one another using the sensors that have been built.
– So, the total activity requires at least three days: the initial meeting; the water sample collection; the overnight equilibration; and the follow-up meeting. 
How to Do This Activity
First, the materials for this workshop need to be acquired, either locally or online. There should be sufficient information in the assembly documentation that facilitators can locate inexpensive sources for the materials.
Anyone interested in water quality might be interested in the content of this workshop; so recruitment might focus on making coning connections between local water quality issues and the ability for participants to ‘hear’ changes in a key water quality parameter — learning about this parameter through doing an activity together. 
The activity itself involves two main steps:  constructing and testing the device, which involves assembling some simple electronics components on a bread board; and then testing water samples, which involves a session in which these sensors are then used to compare various samples against one another.  The interests and ages in the group will drive explanatory discussions around the electronics and the electrochemistry.
In our activity, participants shared their findings by making short videos with their phones of the sensor output, then posting the videos on a google map at the associated water sample location. 
As follow up, participants also wrote up ‘research notes’ on describing what they did, and their reflections on what they did, and how much sense it made to them.  The hope was that by posting online, the participants might also connect with one another about the topic.
Background and Context
Who we are:  “Public Lab is a community where you can learn how to investigate environmental concerns. Using inexpensive DIY techniques, we seek to change how people see the world in environmental, social, and political terms.”
Re: the Coqui water quality workshops:
– Online description of the device:
– Florida International University, using the device:
– Workshop reflections from an Emerson College class:
This was a project that coalesced within the Public Lab community, and was then taken up by professors at Emerson College and Florida International University, as well as by workshop leaders at an alternative education space, Parts and Crafts.


Posted in Citizen Monitoring, Electronics, Sensors