The debate among friends in high school was whether the toilet paper should be scrunched or folded when used. But here in Mexico, the debate includes whether or not the toilet paper should even be discarded into the toilet at all. The answer is a definite maybe.
We must understand the system being used to treat the waste products. And to be clear, when I say, "waste", I am referring to everything that you flush down your toilet. If you have a municipal sewer system, it can handle the paper from the toilets. And if you have a private septic tank on your property the same answer can be true: bacteria in the septic tank can break down the cellulose in the paper. Nevertheless, an excessive amount of toilet paper can be a problem by overloading the tank and slowing the bacterial activity. Hopefully the septic tank is healthy and large enough to handle the volume of material that needs to be treated.
Now we should know that only the villages and towns of the Lake Chapala (i.e. Chapala, Jocotepec, Ajijic, San Antonio Tlayacapan, San Juan Cosala, etc) have municipal wastewater treatment plants to handle the waste from the toilets etc in their respective communities. However, it is common to see in the village businesses, a sign in the bathroom that tells you not to throw toilet paper down the toilet. The problem is not the municipal system but likely the drainpipe between the toilet and the street drain connection.
The typical problem is the type of pipe that has been used. Traditionally, to the street were short sections of red clay pipes joined together. The clay pipes over time become porous and rough on the interior surface and the joints between the sections of the pipes open or, the sidewalls of the clay pipes slowly collapse. The combination of these three conditions do not promote the easy flow of toilet paper along the sections of pipe and the paper or waste product can become hung up on the joints, breaks or rough surfaces. Once stopped along the sidewall, they become the collection point for more and more toilet paper and waste, which eventually clogs the pipes and stops the flow.
Modern drains systems use plastic piping (typically PVC) for the drainage of waste. These systems tend not to have the hang up points along the length of pipe for the toilet paper and hence, less chance for a clog forming in the drain, therefore more favorable to toilet paper movement along the length of the drain pipe.
But that is not all the factor that affects the movement of "waste" along the length of the drainpipe. The slope or inclination of the pipe affects the movement of the waste. If the pipe is too steep the waste flows quickly down the pipe however, elements of the waste could become "stuck" to the side of the pipe and become a point for the future toilet paper to hang up, helping to form larger and larger clogs that eventually plug the drainpipe. Ideally, the drainpipe is sloped or inclined approximately 2% or ΒΌ inch per foot of length, to keep the waste in the pipe, with enough liquid to lubricate and promote the slow but constant movement of waste material along the length of the pipe.
As you are about to throw the paper into the toilet, use your x-ray vision and determine what types of pipes are underground and how they were installed. Easy if you are Superman or, maybe we just need to respect the sign in the restaurant's bathroom.
J. Brad Grieve is a professional civil engineer and has lived and worked in the Lake Chapala area since 1994. He is the owner of Ajijic Home Inspections and you can reach him at (376) 766-2836 or This e-mail address is being protected from spambots. You need JavaScript enabled to view it
