For single-family homes, tanks typically range in size from 500 to 1500 gallons of wastewater storage capacity. For a one- or two-bedroom home, a 1000- or 1200-gallon tank is common; A typical 1000-gallon concrete tank measures about eight feet long by four feet wide and six feet deep.  Check with your local building department for actual sizes needed.

Although a 1500-gallon tank costs slightly more than a 1000-gallon one, it affords more complete digestion and can reduce pumping occurrences by a factor of four or more for a family of three.

• Have your septic tank pumped and inspected every 2 to 3 years. Septic tanks should be pumped out every 2 to 3 years by a reputable septic tank service contractor, who is required to have a state permit to handle and dispose of the material. Businesses are listed in the telephone directory. For more information, you can also call your local County Health Department.

• Use less water. Don't let the water run while shaving, brushing your teeth, washing your hands, washing dishes, etc. Spread your laundry washing out over the week to avoid putting a lot of water into the drain field at once.

• Avoid using chemicals. Chemicals such as drain cleaners, toilet bowl cleaners, and "miracle system cleaners" will kill the bacteria which break down sludge in your septic system. An alternative drain cleaner is 1/2 cup of baking soda, followed by a 1/2 cup of vinegar poured down the drain. Let that sit a few minutes and then follow with boiling water.

• Don't use a septic system for the disposal of anything other than toilet wastes and the water used for bathing, laundry, and dishwashing. The system cannot handle other waste such as cigarette butts, diapers, coffee grounds, tampons, condoms, and grease.

• Keep cars and trucks away from the drain field and septic tank. Never build or pave over the drain field. Driving or building on your tank or drain field can compact soil and break pipes. Soil compaction and paving prevents oxygen from getting into the soil. This oxygen is needed by bacteria to break down and treat sewage.

• Keep a record of when your septic system has been inspected and pumped. 

If the tank has no risers over inspection holes, and no diagram is available showing the location, you will have to probe for the tank, as follows: Use a long metal rod (1/2-inch rebar, bent over 90° to make a handle at the top) and begin probing where the main drain pipe leaves the house. Push the rod firmly down into the soil until you "feel" the drain pipe. Use a firm and steady push. Don't punch or pound the rod as you can damage the pipe, particularly the pipe/septic tank connection. If the soil is too hard and dry for probing, try soaking the area with a garden hose.

Another method: There may be lush growth over the drainfield. Then the tank will be in an obvious place between the house drain and the drainfield. Or, you can run a snake down the clean-out to the tank and locate it with a metal detector.

When you find the drain pipe at one spot, move a little further from the house and probe again. Continue along the path of the drain pipe until you locate the tank. The tank will probably be 1 to 3 feet underground and at least 5 feet from the building. Once you locate it, dig up both manhole covers. Or, if you're lucky, the tank will have risers with sealed caps instead of the very heavy manhole covers of earlier models. If you plan to inspect your own system and don't have these risers, we recommend that you have them installed (contact American Concrete Products for pricing information). In addition to providing easy access for inspection, they keep out dirt and rainwater. In the meantime, use a rope through the metal handles on the concrete manhole covers to swing them up and off the tank. The tank is now ready for inspection and/or pumping.

A septic system should effectively accept liquid wastes from your house and prevent biological and nutrient contaminants from getting into your well into nearby lakes and streams. Anytime these things do not happen, the system is failing.

For example, when waste backs up into your home or liquid is bubbling up in your backyard, the system has obviously failed. If significant amounts of biological or nutrient contaminants reach your well or surface waters, the system is also failing, even though it may appear to be working just fine.

Look for these symptoms to determine if you have a serious problem.

• Sewage backup in your drains or toilets. This is often a black liquid with a disagreeable odor.

• Slow flushing of your toilets. Many of the drains in your house will drain much slower than usual, despite the use of plungers or drain cleaning products.

• Surface flow of wastewater. Sometimes you will notice liquid seeping along the surface of the ground near your septic system. It may or may not have much of an odor associated with it.

• Lush green grass over the absorption field, even during dry weather. Often, this indicates that an excessive amount of liquid from your system is moving up through the soil, instead of downward, as it should. While some upward movement of liquid from the absorption field is good, too much could indicate major problems.

• The presence of nitrates or bacteria in your drinking water well. This indicates that liquid from the system may be flowing into the well through the ground or over the surface. Water tests available from your local health department will indicate if you have this problem.

• Buildup of aquatic weeds or algae in lakes or ponds adjacent to your home. This may indicate that nutrient-rich septic system waste is leaching into the surface water. This may lead to both inconvenience and possible health problems.

• Unpleasant odors around your house. Often, improperly vented or failing systems cause a buildup of disagreeable odors around the house.

• Call your local health department. This is the first thing you should do. Health department staff members have the expertise to assess your situation quickly and offer advice on how to cure the problem.

• Have your septic tank pumped. Frequently, this will help the problem temporarily, especially when it is combined with drastic water conservation. The empty tank can hold several days of waste. (This won't be effective if a clog exists between the house and the septic tank, or if very high water levels are the cause of the problem).

• Conserve water in your home. This is particularly effective if your system has not failed completely. It can help lessen the problem for a short time. Water-saving devices and reduced consumption, especially in your bathroom, can have a significant effect.

• Fence off the area. If liquid waste is seeping to the surface, prevent people and pets from getting in contact with the effluent.

In many cases, redesigning and replacing the system in a new location is the only practical long-term solution. This type of work should be completed only by a qualified contractor. Local health department permits are required before construction can begin. The chemical cures sometimes advertised are ineffective remedies for severely damaged systems. Other solutions may be of help in some situations, including:

• Increase the size of the absorption field. This will help if the original field was too small for the size of your family or if the soil does not allow water to percolate very well.

• Conserve water in your home on a long-term basis. The smaller the amount of water flowing through your system, the longer it will last. For systems that perform marginally or leak nutrients into nearby lakes and streams, this is a good alternative.

• If periodically saturated soils are a main cause of problems, consider installing perimeter drains. This system involves installing tile drains underground at a specified distance around the absorption field to help lower water levels. It works in some but not all situations and requires the assistance of a qualified contractor. Its location should also be evaluated by your local health department.

• Connect to a community sewage system, if one is available. Although the long-term costs may seem high, the benefit of reduced worry and greater responsibility are often worth this price.

• If septic system failures are common in your area, consider participating in the development of a small community "cluster" system or other similar alternatives. These systems are designed for small communities and some rural areas and are generally much more cost effective than large sewer systems.