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Causes of Septic Problems

Find out the causes of septic system problems, and learn what you can do to avoid them.

In this article, you will find:

What goes wrong
How overloading happens
No-no's for septic fields

How overloading happens

Overloading the System

Inadequate size is another common septic-tank problem that results in poor treatment and overloaded drain fields. Septic tanks are sized to accommodate the number of bedrooms in the homes they serve. This number gives installers a rough idea of how many people occupy the home and how much waste the system has to treat.

The following chart shows the relationship between septic-tank size and the number of bedrooms:

No. of Bedrooms Tank Capacity in Gallons
2 or fewer 750
3 900
4 1,000

If you've added family members or added onto your home, your septic tank might be too small to handle the additional load. Drain fields are also sized by the number of bedrooms in a house, with a typical rate being 50 linear feet per bedroom. Adding on can also make them inadequate. Depending on the field's location and construction, it might be possible to improve or expand it.

Another type of septic-system overload can occur during the spring when water tables are high. When this happens, saturated soils slowdown and sometimes halt system operations.

Homes sited on flat lots with poor surface drainage are especially susceptible to ground water problems. Depending on the severity or the problem, it may be necessary to lower the water table by installing drain tile. The tile should discharge to a surface ditch or a larger drain system located away from the drain field.

Excessive Water Usage

Around the House

Washing machines are a leading cause of septic-system failure. A typical wash cycle can use up to 62 gallons of water. Doing more than a couple of loads in a day can easily overload a small septic tank or one that's full of sludge.

As mentioned in All About Septic Systems, septic systems are slow-moving devices. They need to work slowly because bacteria and other organisms in septic systems aren't real speedy when it comes to breaking down household waste, and they can only handle a certain amount at a time. Plus, it simply takes time to separate liquids from solids.

The less water you pour into your septic system, the more time it has to do its work well. Push too much fluid through the system too quickly, and untreated solid material can flow into the drain field, again causing clogs.

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