We updated our septic system at Grampari during the summer! And we’re excited to tell you about it! It’s funny how much thought we typically put into what goes into us (clean water and tasty foods) and how little we put into what goes out of us and where it goes! So here’s a brief overview of our new and improved septic system which allows for as well as some info on how they work. A septic system is an on site sewage treatment plant (to treat black water which is toilet waste) and consists of a septic tank and a drainfield.
The septic tank is a buried box made up of two chambers. Black water consists of solids and scum. The septic tank works by holding the black water until the scum floats, the solids settle and allowing anaerobic bacteria to digest the solids, thus reducing their volume. The middle layer (above the solids and below the scum) passes from one chamber to the next through a T pipe or hole in the middle of the separating (or baffle) wall. This middle layer is called effluent and though much less dangerous than the incoming untreated black water, is still highly pathogenic and needs to be further treated. (Aside: it may seem obvious but safe disposal of human waste is one of the most important ways to keep communities healthy. In fact, in 2007, more than 11,300 readers of the British Medical Journal chose sanitation as the most important medical milestone of the last 150 years.)
This effluent is often left to drain into gutters or empty fields. This practice, though common is incorrect and dangerous, and can lead to the contamination of drinking water wells or future crops. The effluent needs to be further treated and this is done by routing it to a leachfield or drainfield from the final chamber of the septic tank. The leachfield slowly releases the effluent into the soil which acts as a filter to remove the harmful bacteria.
In Grampari, the old septic tank was undersized and the effluent improperly treated. To accommodate our 6 toilet bathroom that tends to 50 users during workshops, we needed to build a larger tank and find a way to properly treat the effluent, especially since our organic garden is located near the septic tank.
Well, there you have it – everything you wanted to know and more about our septic system (and perhaps slightly more!). So, do you know where YOUR black water goes?