From NHDES Environmental Fact Sheet BB-11; Greenworks, NHDES Nonpoint Source Program, March 1997; and You and Your Septic System, NHDES, Subsurface Systems Bureau.
Septic Systems and Your Lake's Water Quality
How do septic systems work?
Septic systems act as the digestive tract for household organic waste and destroy disease-producing bacteria. The most commonly approved systems today consist of a septic tank connected to a leach field. The septic tank stores solid organic waste, and pipes waste water into the leach field where it is filtered and drained into the soil below.
How is water quality related to septic systems?
Certain nutrients build up in organic waste from your home and are dissolved in the water that ends up in the leach field. The nutrients that do not get filtered out eventually drain into the water table below the ground or drain into rivers and lakes that may be nearby. Nutrients-especially phosphorus-are vital to plant and algae growth. High levels of phosphorus, however, act as a fertilizer and create an environment where growth is unnaturally rapid. This deprives aquatic animals of vital dissolved oxygen and will speed up the life cycle of a lake through the build up of plant and algal matter.
What can we do to help water quality?
In order to alleviate the problem of phosphorus build up, each of us must act responsibly when addressing waste disposal. If you are at all unsure about your septic system please call a licensed septic hauler or your town official to determine the health of your system. If your system is 20 years or older, chances are good that it is outdated.
If you don't know where your septic tank and leachfield are, contact the town office to see if there is a plan on file. For an older system, you can generally find the septic tank by running a plumbing snake down the cleanout plug in the sewer pipe, following the pipe to where the snake stops, and measuring the length of snake fed out. Most tanks can be found about 15 to 25 feet from the house approximately 12 to 18 inches below the surface. You can also try locating the steel reinforced tank cover with a metal detector.
Most leachfields lie in a straight line from the tank. You may be able to locate the leachfield by noting where the snow has melted after the first frost or light snowfall of the year. Or, try probing the ground with a rod. Where you hit crushed stone is likely the leachfield. Map the location of both your septic tank and leachfield for future reference.
Please keep this reference in a convenient place and post if you have tenants
WHAT CAN WE DO TO PROPERLY MAINTAIN OUR SEPTIC SYSTEMS?
Inspect your septic tank every year. If the sludge and surface scum combined are as thick as 1/3 the depth of your tank, have the tank pumped by a licensed pumper.
Pump your septic tank when needed and at least every 2-3 years even if you only use it seasonally or on weekends.
Compost your kitchen garbage rather than using a garbage disposal. This keeps many nutrients from directly entering the water system.
Report any sudden increase in aquatic algae or plant growth to the proper officials. This may be an indication of a phosphorus overload.
Conserve water whenever possible. The more water in your septic system, the greater the possibility of nutrients leaching out through the system. Five gallons of water to flush a bug is ridiculous!
Never flush toxic materials (such as paint, oil, or pesticides) down your drain. Not only do you risk the possibility of tainting your own drinking water, but you will also kill natural bacteria in your septic systems that will break down organic waste.
Avoid flushing bulky materials or grease down the drain. These will often clog your system and slow the decomposition process.
Use phosphate-free or low phosphate dishwashing detergents. Joy is phosphate free.
Run laundry or dishwashing cycles after a full load has been collected. This not only conserves water but will cut down on the number of phosphates that drain into your septic system.
Don't use colored toilet paper, it does not break down in the tank as rapidly as white paper.
If you have any soggy areas around the system, any disagreeable odors, or any back up in the pipes you are likely to have a system failure. Call a licensed septic hauler or town official immediately.
MAINTENANCE RECORD
Location of Septic Tank. In the space below make a sketch of your house. Measure and record distances from the foundation to the septic tank or cesspool cover, to the distribution box, leaching system and to other permanent structures such as nearby trees or rocks.
Date System Installed_________________
Installer____________________________
Pumping/ Pumper/
Date Maintenance Contractor
_____________________________________________
_____________________________________________
_____________________________________________
_____________________________________________
