Conventional septic systems can function very well with minimal care. In fact, most septic tanks will only require an inspection and pumping out by a professional every three to five years if they are used properly. This does not pertain to I/A systems, which need more frequent oversight.

DO ... 

Do have the system inspected and pumped every 3 to 5 years. If the tank fills up with an excess of solids, the wastewater will not have enough time to settle in the tank. These excess solids will then pass on to the leach field, where they will clog the drain lines and soil.  More information on pumping .

Do know the location of the septic system and drain field, and keep a record of all inspections, pumpings, repairs, contract or engineering work for future references. Keep a sketch of it handy for service visits.

Do grow grass or small plants (not trees or shrubs) above the septic system to hold the drain field in place. Water conservation through creative landscaping is a great way to control excess runoff. 

Do install water-conserving devices in faucets, showerheads and toilets to reduce the volume of water running into the septic system. Repair dripping faucets and leaking toilets, run washing machines and dishwashers only when full, and avoid long showers. 

Do divert roof drains and surface water from driveways and hillsides away from the septic system. Keep sump pumps and house footing drains away from the system as well. 

Do use only additives that have been allowed for usage in Massachusetts by MassDEP. Additives that are allowed for use in Massachusetts have been determined not to produce a harmful effect to the individual system or its components or to the environment at large. 

Do take leftover hazardous chemicals to your approved hazardous waste collection center for disposal. Use bleach, disinfectants, and drain and toilet bowl cleaners sparingly and in accordance with product labels. 

DON'T ...

Do not use your toilet or sink as a trash can by dumping non-biodegradables (cigarette butts, diapers, feminine products, etc.) or grease down your sink or toilet. Non-biodegradables can clog the pipes, while grease can thicken and clog the pipes. Store cooking oils, fats, and grease in a can for disposal in the garbage.

Do not put paint thinner, polyurethane, anti-freeze, pesticides, some dyes, disinfectants, water softeners, and other strong chemicals into the system. These can cause major upsets in the septic tank by killing the biological part of your septic system and polluting the groundwater. Small amounts of standard household cleaners, drain cleansers, detergents, etc. will be diluted in the tank and should cause no damage to the system.

Do not use a garbage grinder or disposal, which feeds into the septic tank. If you do have one in the house, severely limit its use. Adding food wastes or other solids reduces your system's capacity and increases the need to pump the septic tank. If you use a grinder, the system must be pumped more often.

Do not plant trees within 30 feet of your system or park/drive over any part of the system. Tree roots will clog your pipes, and heavy vehicles may cause your drainfield to collapse.

Do not allow anyone to repair or pump your system without first checking that they are licensed system professionals.

Do not perform excessive laundry loads with your washing machine. Doing load after load does not allow your septic tank time to adequately treat wastes and overwhelms the entire system with excess wastewater. You could therefore be flooding your drain field without allowing sufficient recovery time. You should consult your tank professional to determine the gallon capacity and number of loads per day that can safely go into the system.

Do not use chemical solvents to clean the plumbing or septic system. "Miracle" chemicals will kill microorganisms that consume harmful wastes. These products can also cause groundwater contamination.