Septic Tank Fun

A septic system is a self-contained, underground wastewater treatment system. In some neighborhoods residential and commercial buildings use septic systems in place of large municipal sewage systems. In houses with septic systems, every toilet is connected to the septic tank which is usually located outside the house and buried underground . Because septic systems treat and dispose of domestic wastewater onsite, they are often more efficient than central sewer systems. This is often true in rural areas where lot sizes are bigger and houses are spaced apart.

How they work

A septic system usually consists of two chambers or compartments. Water runs out of the home through one major drainage pipe into the primary septic tank.

The stillness of the tank contents allows solids to settle to the bottom, forming sludge, while oil and grease floats to the top as crust. The fluid wastewater then exits the tank into the drain field.

The drain field is a shallow, cover, excavation made of unsaturated soil. The soil accepts and passively treats the wastewater, finally discharging to groundwater. The water is said to “percolate” through the soil.

Typical size for residential houses

The most important thing to consider before installing a new septic system are the size of tank required. The size of the septic tank you will need depends typically on the size of the home and the amount of people who will reside there. Generally residential septic tanks range size from 750 gallons to 1,250 gallons. · 750 gallon septic tank for one and two bedroom house below the 1,500 square feet.

Typical size for larger buildings or groups of buildings

Superior, multi-chamber septic tanks can be planned for group of houses and/or public buildings (e.g., schools).

A septic tank is suitable where there is a way of dispersing or transporting the sewage. Commonly for larger building or groups of construction the septic tank size above the 1,250.

Material of construction

Septic tanks should be waterproof, structurally strong and constant. As a construction material, reinforced concrete effectively meets these necessities. Steel is a further material that can be used for septic tanks but should be properly covered for corrosion resistance. Plastic and fiberglass tanks also are used.

Three most common septic tank possible problems

  • Tree root damage – If roots penetrate the tank, there can be movement of water from outside the tank to inside, and the other way around - which is the release of yucky stuff (septage) to the environment.
  • Ground movement – the soil and rocks near the septic tank can shift, often without it being visible above ground.
  • Vehicle damage

How often sludge is removed

Septic tanks must be periodically serviced to remove accumulated sludge. The material removed is called septage. This is almost always done with a truck-mounted pump.

If too much sludge accumulates, wastewater solids will run to the soil absorption area causing system failure (especially from older tanks that do not have outlet filters. To prevent that, the tank should be pumped before it gets too full, and many property managers have a set schedule.

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    Mobile, AL 36602