The history behind the modern conventional septic system explains how the conventional septic system evolved by accident not design. The modern conventional septic system didn’t require learned men or women with specialized knowledge, merely good luck and reasonable logic looking at a series of problems over centuries of time. The microbial underpinnings of septic systems were not understood. Bacteria were not known until “discovered” by Louis Pasteur. Only after the basic design was found to function consistently, did anyone with a modicum of expertise look into the “whys”. Modern “experts” reverse engineered the conventional septic system to understand what was actually taking place. The following outline will explain how early communities and cities started a waste disposal process that eventually led to the modern conventional septic system. You’ll discover it wasn’t a complicated process.
Before agriculture, human beings dropped their waste and moved on the same as every other animal on the planet. Humans dropped their wastes on the ground, possibly kicked a bit of cover on it, and walked off never giving the process another thought. Twelve to fifteen thousand years ago our ancestor’s discovered agriculture. This profoundly and fundamentally changed the way our ancestors lived. Our ancestors began living in larger and larger groups and formed stable, fixed place communities or cities for economy of labor and mutual protection. In a relatively short period of time, our early city dwelling ancestors found it necessary to change the way they disposed of their wastes.
Because agriculture depended on water, these early communities were built near dependable water courses. For mutual protection, these early cities constructed protective walls around their homes. As community populations increased, it became obvious that individuals could no longer walk out into the hinterland and drop their wastes on any patch of “public” ground. This problem is easy to understand; the more people, the more droppings; the more droppings, the more difficult to walk freely around. The more people, the further one would have to walk to dispose of their waste. This was not only inconvenient but could be down right dangerous. The further the distance, the more likely one might encounter a predator or an enemy. A 6,000 year old Sumerian city had the first evidence of a solution to this problem.
Some clever people in Sumer figured out that water upstream of the city could be transported in stone lined ditches under the city walls, pass through the city and then exit under (again) the city walls. Without knowing it, our ancestors were using gravity to take their wastes away. Within the city, stone benches with appropriate holes were constructed over this ditch so waste could be deposited in the flow of water to be carried out of and away form the city. “Away” meant to the water down stream of the city. Eventually, the Romans had the most sophisticated application of this type of waste system. By this method, the habit of putting our wastes in water most likely began.
When our ancestors began using water to take their wastes away, going to the “bathroom” became a substantial net loss over all. Construction and maintenance of a waste system, payment for the right to use the system (taxes), degradation of the environment from concentrated human waste, upgrading and repairing existing waste treatment and disposal systems and paying people to maintain waste systems are a few of the losses we still incur. On planet Earth, there is no loss to any other animal for passing its waste, except human beings.
Here’s how putting waste in water to take it away by gravity finally became the modern conventional septic system. As human civilization grew and flourished, each culture had to solve this same crucial problem; what to do with human waste? For our European ancestors, the “outhouse” was the “common place” to put human wastes when there was no water course for them to use. It was called an “outhouse” because it was located outside of their dwellings. When the outhouse pit filled up, one merely dug another pit near by and moved the “house” over the new pit. Within a couple of decades, the contents of the prior pit degraded. After enough time had elapsed, one could again use the same spot for a subsequent pit. With the invention of the flush toilet by the English company “Crapper” in the late nineteenth century, putting human waste in water to carry it away again became a “necessity”. Now people could stay in the house. Who wouldn’t rather sit on a “Crapper Toilet” in a “water closet” inside the house, instead of going outside to a rather dirty and smelly outhouse in the heat of summer and the wet and freezing cold of winter? “Inside plumbing” became popular so quickly that social status was often marked by this feature of a home. The inside flush toilet became a necessary appliance in every home through out the “civilized world” that could afford one (or two or three). The terms “crapper” or “crap” exists with us today and their meaning is well known and understood.
The outhouse pit was typically small and unlined because there was little liquid to destabilize the soil. The addition of flushing water with waste into the “outhouse pit” made for frequent problems from hydraulic overloading and soil collapse. The next innovation in the evolution of a conventional septic system was a “natural” extension of the outhouse with a “Crapper”. We call this innovation a cesspool.
The cesspool was constructed to hold substantially more liquid volume. There was a liner of stone, brick or wood to keep the walls of the cesspool from collapsing inward due to the constant exposure to water and waste (we now call this liquid effluent). As household water use increased, the cesspool needed more maintenance (solids removal) and frequent rebuilds from clogged soils. The next step was the septic tank and leaching field to extend the functional life of the “system”.
The basic idea of the septic tank and leach field was to allow the septic tank to retain the bulk of the waste within the tank (exactly like the cesspool) but easier to clean (now pumping out solids) and to increase the life of soil disposal of the liquid by having trenches filled with porous rock that would give the liquid many times more surface area than the soil around a cesspool. Voila, the modern conventional septic system was born! Change the holding capacity of the septic tank and/or increase the size of the disposal field and you have the means to extend the life of the conventional septic system to an acceptable period.
Fortunately, the simple septic construct worked with minimal oversight for the reasonable periods expected before failure. This progression or evolution of the modern conventional septic system was logical and simple but created by accident not by design.