It seems generally true that you don’t need to know how something in your home works until it stops working. A few months after we moved into our house in 2006, Jenine and I started learning about our septic system. An alarm went off in our garage in the middle of the night. Over the next day or so we learned that our septic system has two pumps for moving liquid from one part of the system to another, and one of them had stopped working. The alarm indicating that a “pump tank” was nearly full. Replacing the broken pump cost over $1000. 13 months later (just after the warranty expired) the pump failed again, necessitating another four-figure investment in our home. We haven’t had any problem in the subsequent 2 ½ years, but that second failure left a lot of unanswered questions: Was the pump “burning out” for some reason? Could ground water have been getting in to the system, causing the pump to run excessively? Could the pump have been “stuck on” somehow? Was the pump pushing against a downstream clog? The experience basically left us wanting to know what the heck is going on down there. I started looking around for some device that would track and report on the septic system activity. The closest thing I could find is a run-time meter, which just tells you how many hours a device has been on in its life time. What I really wanted was a device that would give a daily summary so I could see the baseline activity, any seasonal trends (more activity in the Fall/Winter might mean a ground water leak) and any sudden change (the pump suddenly stopping altogether or suddenly going on a lot, the latter meaning that a switch is stuck on or that the pump is pushing against a clog).
Not finding a suitable device for sale, I ended up making my own, using an old Palm Pilot and a few miscellaneous electronic bits. The monitor has run for over two years, showing that the pump tank pump runs for an average of about four minutes/day.
More recently I decided that it would be more convenient to have a web-based version of the monitor, so that the activity could be seen on any computer, rather than just on the little Palm Pilot screen in our garage. I found a low cost way to connect a sensor to the internet and set up a web-based program to display the data. You can see our septic system activity by looking at the "live demo" at:
http://omwatcher.appspot.com/
It shows the activity of both pumps in our system. You can also see where we went out of town in June (no activity). The sand filter pump sensor was added on June 6, which is why there aren’t any bars before that. The system also has a number of 'checks' that it runs daily, to see if it's broken or if the monitored pump(s) are on too much or not enough.
The program can track and display the activity for any number of households, having any number of sensors each. Moreover, the wireless technology makes it possible to add more sensors and/or households to the existing so-called Home Area Network (HAN), limited only by the range of the wireless devices. Our next door neighbors have just one pump in their septic system, and are now tracking it using the same web-based program.
I'd like to add more households to this system. I understand that there are "operation and maintenance" professionals who contract with homeowners to maintain their septic systems. My thought it that this tool could enhance such a service, a trained professional being the best one to monitor and interpret the run information.
