Using the restroom in comfort is one step closer here at the house in Ojo de Agua. We just finished the septic waste water treatment system.

I decided to go with a two tank system that supposedly treats the water enough to be later used for grey water irrigation. First, the toilet water flushes to a normal plastic septic tank with baffles where the majority of the sediment settles to the bottom and the “black water” carries on to the second tank. The second tank has a false plastic bottom about five inches deep that creates a space where the four inch diameter perforated outlet pipe from the first tank drains. The dirty black water comes up from under the false bottom and filters up through about two feet of gravel to where it skims into another perforated PVC pipe and drains into the leach pit.

The directions for the system call for a small leach pit where the grey water can flow into another perforated pipe and out to a drain that can be used for irrigation purposes. Since I have no shortage of water due to my spring fed water system with back up well I choose not to have a drain. Irrigation here in Ojo de Agua is not a problem.

I converted the grease trap that came with the system into my leach pit. I’m running all the other kitchen and bath fixtures to composting grey water platanos or banana pits, so no need for a grease trap. I drilled holes into the side of the small grease trap tank around the middle and filled the tank and surrounding area outside of the holes with river rocks and gravel. I sandwiched the gravel outside of the tank in between geo-textile cloth to keep out the dirt. I buried a exit pipe with a cap in case I ever do decide to have a drain and also left a T with a pipe sticking up covered and protected under a valve box so I can know exactly where the drain is in case of future irrigation needs and to be a able to keep an eye on the water level and clarity in the leach pit.

After the tanks were set into place we back filled and compacted the dirt around the outer walls of each tank while filling the tanks with water, maintaining a consistent equal level of both dirt and water, the water pressure keeps the weight of the soil from caving in the tanks sides. We compacted every few inches so it took quite a few days for me and Jose Maria to finish the job. Luckily it rained almost every day in the afternoon so the rain helped compact the soil we had worked on.

The instructions for the system recommended the construction of solid concrete lids over the tanks. Instead, I took some of the leftover M2 panels from the house construction and stuccoed them and placed them over the tanks. I layered them between geo-textile cloth to keep them clean in case I ever have to open up the system for cleaning or maintenance. These panels are really strong and much lighter then solid concrete.

I have seen many people building here with septic problems including commercial businesses on the ocean, friends and neighbors. Tanks have been known to sink, walls collapse and also not drain sufficiently. Some folks here have concrete tanks constructed and many times they end up with a ugly concrete square in the middle of the yard from the exposed lid being to high. As with a lot of things here in Panama I like to search for a method or system where the majority of the work I can do myself or with minimum laborers and always try to leave an easy manner to access and maintain. Especially something as important as a septic system. I hope to never have a problem with something that could be so smelly.

Dexter was so impressed by the system that he decided to take a swim in the tank before I sealed it up. I think he enjoyed his self.