What is a septic system?

A septic system is a large filter. Like all filtering mechanisms, there are components that require maintenance for it to continue to operate effectively. When filters are neglected, over time they begin to fail. With a septic system the failure can result in many costly and unsafe problems such as:

• Septic coming up in your yard
• Septic coming back into your home
• Replacement of parts of the system
• Replacement of the entire system….if the area even permits the replacement.  Once again, this is up to the findings or rulings of the Department of Health.

Components and Construction of a Septic System

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In-Put Line:  The in-put line is the pipe that carries waste from the house to the septic tank. 
Materials: PVC, Cast Iron, Terracotta, Orangeburg

In-Put Tee:  A “T” shaped pipe that fits on the end of the in-put line.  Its function is to direct the waste straight down into the tank.  This keeps the waste from stirring up material in the tank, causing the release of unpleasant gases and helps to keep the hard materials from entering the distribution area. 
Materials: PVC, Cast Iron

Septic Tank:  Septic tanks are designed to hold the waste and operate at nearly full capacity.  The crust should be just below the in-put tee.  The hard materials or sludge drops to the bottom, the liquids are in the center and a film of crust or scum on the tom.  The fluid in the center is what flows over the distribution area.  The hard waste materials that are stored in the bottom of the septic tank should be cleaned and vacuumed out on a scheduled routine basis to prevent them from reaching the distribution area.  The Department of Environmental Health recommends that a septic tank should be cleaned every 3-5 years depending on usage.

Out-Put Tee:  A “T” shaped pipe that extends down the center of the tank, allowing liquid waste to drain from the septic tank to the distribution box.  Without the out-put tee, hard materials may enter and damage the distribution area of the septic system.  Materials: Reinforced Concrete.

Out-Put Line:  This line carries the liquid waste from the septic tank to the distribution box. 
Materials: PVC, Cast Iron, Terracotta, Orangeburg

Distribution Box:  A 1’ x 3’ box (on average) with port holes that header lines attach to.  The distribution box (D-Box) allows the liquid waste to drain evenly into the field lines.  Material = HDPE, Concrete

Header Lines:  The pipes that connect the distribution box to the field lines. 
Materials: PVC, Terracotta, Orangeburg

Field Lines:  This is the absorption part of the septic disposal system.  The number and length of the lines will vary from system to system.  Field lines, perforated pipes, are the filter of the system.  The liquid waste is evenly distributed, filtered by the soil and purified by natural processes. 
Materials: Corrugated plastic, Terracotta, Orangeburg, Gravel Pit

Pump Tank:  This is a liquid waste holding tank (generally 1,000 gallons) for pump back systems.  Liquid waste flows from the septic tank to the pump tank.  When the liquid reaches a certain level it raises a float that turns on a pump to force the liquids up to the distribution box. 
Materials: Reinforced Concrete

Manhole:  A port that provides easy access to the backup pump.  It is wise to install a manhole over the septic tank to avoid unnecessary digging in addition to allowing for emergency access should a back up problem occur. 
Materials: Concrete, Plastic.

Back or Lift Pump:  A pump used to distribute liquid waste from the pump tank to the distribution box.  The horsepower ranges from ½ to 1 ½ hp, depending on the size of the septic system and the distance the fluid must travel. 

Important:  In the event your alarm for the back pump system activates, turn off the pump at the electrical breaker box immediately.  Then call a professional back pump specialist.  You do not have time to drag  your feet, a system back-up is eminent.

In the past, materials used to install septic systems were not as durable as those used today.  The terracotta and cast iron pipes blister from the inside out and become very brittle.  Orangeburg pipe is made of pressed cardboard and breaks easily.  Tree roots along with the freeze and thaw of the ground take their toll on these materials.  Pipes become weak, clog and eventually collapse, causing a system failure.

Garbage Disposals:  Homes that have and regularly use a garbage disposal need to have their septic tanks cleaned more frequently.  Every 3 years is recommended.

Steps to Obtain a Septic System

You can find companies to get pricing on a septic system, but until you have the Virginia Department of Health come to your property to test the soil and design a system, no one can give you a very accurate price. 

Before a septic system can be installed, the law requires that you obtain a permit and plan through the Department of Health.  You must go there and apply for the system.  They will go to the site, test the soil conditions, determine the tank size and field lines by the house and number of bedrooms.  If a standard system does not apply the Department of Health will recommend alternative options.