Pumping Your Septic Tank

septic tank inspection

Although not a part of the home inspection, if you live in a rural area of San Diego or Riverside Counties you're probably familiar with the form and function of a septic system. In simple terms, a septic system is your private onsite sewage treatment facility. It’s used primarily where access to a municipal sewer system is either unavailable or economically unfeasible. A septic system is out of sight and is odorless (when properly maintained).

maintenance free septic?

A septic system is reasonably maintenance-free. A well-constructed, properly maintained tank could last indefinitely. However, the drain field (the underground area where all of the sewage drainpipes are located) will most likely require some treatment or perhaps replacement after about 15 to 20 years of service.

prolonging the life of your septic system

According to the experts, you can prolong the life of your drain field by performing regular maintenance on your system. This home inspector recommends that you have your system inspected annually to detect any signs of malfunction. Problems caught early can prevent thousands of dollars in repairs. It is also recommended that you have the tank drained on a regular basis. How often is determined by the size of the tank and the number of occupants in the home.

Other factors also come into play, ie: garbage disposal, water softener, etc. Your tank should be inspected by a qualified professional to determine whether pumping is necessary for your system.

Other factors also come into play, ie: garbage disposal, water softener, etc. Your tank should be inspected by a qualified professional to determine whether pumping is necessary for your system.

saving money on your septic inspection

To save yourself some money you can expose the manholes ahead of time. Otherwise the pumping company will charge you extra to locate and expose the openings. Hopefully you  have the "as-built" drawings, or something from the previous owner showing the location of the manholes (yes, there are two).

If not, then just pay the extra to have them find the manholes. If the installer provided risers for the manholes, you're in luck. The cover should be no more than six inches below the surface. If not, then you may have to dig to a depth of as much as two feet or more. 

Luckily this one has a riser and is only about six inches below the surface. The first one is the most difficult to locate. Once you find it, the second manhole should be about sixty (60)  inches away (center-to-center).

Luckily this one has a riser and is only about six inches below the surface. The first one is the most difficult to locate. Once you find it, the second manhole should be about sixty (60)  inches away (center-to-center).

pumping your septic tank

After the second manhole is located and exposed, the inspection and pumping can begin. The inspector will start by measuring the levels of the scum, water waste, and sludge. The sludge is the solid waste at the bottom of the tank.

sludge in your septic

The sludge should measure no more than one-third of the depth of the tank. Otherwise the solids will enter the secondary chamber and make their way to the leach field where they will plug the lines and cause failure of your drain field.

Primary chamber is open, levels are measured, and it is determined that this tank is in need of pumping.

Primary chamber is open, levels are measured, and it is determined that this tank is in need of pumping.

This is a view of the secondary chamber. The white pipe is the point at which the waste enters the drain field. You do not want solids in this tank as it will lead to blockage of the drain field. The "T" fitting helps prevent solids from entering the drain field.

This is a view of the secondary chamber. The white pipe is the point at which the waste enters the drain field. You do not want solids in this tank as it will lead to blockage of the drain field. The "T" fitting helps prevent solids from entering the drain field.

processing the waste water

The waste is pumped into a tanker truck for "processing". The truck pictured is the only one like it in the United States. It is a miniature water treatment plant. It processes the waste in  much the same way as any large waste treatment facility.

The truck separates the solids from the water and returns the "clean" water to the tank. The solids are reduced to a 10% moisture content and transported to a drying field to be used as compost after it has aged.

truck.jpg
You can watch the separation process through the viewing window on the truck.

You can watch the separation process through the viewing window on the truck.

clean water put back in the septic tank

Once the processing is complete, the "clean" water is pumped back into the holding tank. By re-using this water instead of replacing it, your system gets a headstart on the good bacteria that is required to process the waste in your septic tank. And as a super bonus, if you're in California, you're conserving good drinking water.

The water is not drinking water clean, but you can see how clear it is as it's pumped back into the septic tank.

The water is not drinking water clean, but you can see how clear it is as it's pumped back into the septic tank.

bottomline for your septic

I've just touched on one small aspect of your septic system. The EPA has an excellent homeowners guide for maintaining your septic system. You can download it here.

TIP: Once you have located the manholes, take a picture, or draw a diagram with measurements to reference points for use in the future, or for handing off to the next owner.