Posted By lpercifield ~ 4th April 2012
On of the great outcomes for the Water Hackathon held March 23-25 was a new version of CSO sensor that seems very promising.
First and foremost, this sensor was a collaboration with Dan Seldon, Dustin Goodwin, Daniel Soto, John Feighery, Joe Saavedra and many more. You guys ROCK!
The idea behind the design of this sensor was to create a device that could be installed outside of a CSO (combined sewer overflow), in a publicly accessible place, and would use a variety of different sensing techniques to detect when a sewer overflow happened. The group decided that the first sensor would be water temperature. Even when mixed with storm runoff, overflows should be measurably warmer than the receiving waterbody. The temperature probe that we used is a waterproof digital sensor from Adafruit here in NYC.
For the second sensor, we decided to create our own electrical conductivity (EC) probe. The EPA has a some great details about EC and how its an indicator of water quality. Basically the more pure the water the lower the conductivity. Conversely, the more stuff, in our case sewage, thats in the water the high the conductivity will be.
There is great book recently published called Environmental Monitoring with Arduino which includes plans for a DIY EC sensor. Using parts from Radio Shack the team created our EC sensor and calibrated it with solution from Atlas Scientific.
These two sensors were connected to a custom arduino shield which was milled on the awesome Parsons PCB machine.
Everything was connected to an Arduino including a big battery, a charging circuit and a solor panel all from Adafruit and a GPRS Shield from SeeedStudio. This all was put into a small Pelican case and prepped to be installed in the Gowanus Canal.
The sensor is currently offline but will be back up soon after some updates! Check out the Pachube feed!
Thanks again to everyone who participated!