Septic System 101

For septic system owners, follow a few key steps to keep your system working properly. A healthy septic system helps to keep our groundwater healthy!

septic system diagram

Septic system diagram.

 

Contrary to what many people think, septic systems are better for the environment than sewers.

  • Septic systems treat wastewater, then recycle it locally, into the ground, where it helps to sustain ponds, streams, wetlands and wildlife.
  • Sewers send wastewater to a facility to be processed, which might be many miles away from the homeowner’s property.  In the Neponset River Watershed, sewer systems lead to the Deer Island Treatment Plant, where it’s processed and then released into Boston Harbor.

Water-testing data shows that most water pollution problems in the Neponset Valley are caused by sewer systems.

You probably never thought of it this way, but by cleaning and recycling our water, septic systems keep water local, and help to make our communities a beautiful place to live.

How Septic Systems Work

When you flush your toilet, take a shower, or rinse food down the sink, you are creating wastewater. Wastewater is made up of two very different components: liquids and solids.

septic-tank-e1418090216376

Septic holding tank.

The solids are captured in your septic system’s “holding tank.”  The holding tank is a big concrete box where your wastewater sits quietly for a while so that solids can sink to the bottom or float to the top. The solids are then stored or “held” in the holding tank until they can be removed by a septic system contractor.

While the solids are being held, bacteria break-down the waste and reduce its volume. The solids in your holding tank shrink as they break down, but they never disappear. Eventually, the solids have to be cleaned-out.

Once the solids have separated from the liquids in the holding tank, the liquids flow out of the tank to the “leaching field.” The leaching field spreads the liquids over a large underground area. Beneficial bacteria in the soil digest the pollutants in the liquid, and then the purified water percolates through the ground to join your community’s groundwater.

 

This short video shows the basic operation of a septic system.  Keep an eye out for the baby!

How to Maintain Your Septic System

Using a properly maintained septic system costs considerably less than paying annual sewer usage fees. However, when septic systems are not properly maintained, they can cost a bundle.

A septic system ignored for years is more or less guaranteed to cause water pollution and create big repair bills. You wouldn’t try to drive your car for 100,000 miles without an oil change. Yet without thinking about it, many people routinely dump ten years worth of waste into their septic system, and expect it to disappear. Septic systems are extraordinary devices, but they’re not magic.

This is why we advise you to follow these simple rules of septic system maintenance. Together, we can save money and keep the Neponset Watershed’s waterways clean and flowing!

Septic System Maintenance Guidelines:

Pump it! Keeping your system clean with regular pump-outs is the most important step in septic maintenance.

  • Most people should have a septic system contractor pump-out their system every other year.
  • People using garbage disposals and those with very large households will probably need to pump every year.
  • Very small households may be able to go 3 years between pumping.

Pumping is cheap insurance, so when in doubt, pump it out! Regular pumping will keep solids from spilling out of the holding tank and ruining the leaching field. It will also help you find and fix small problems before they become big headaches. Also, remember that chemical additives or septic system cleaners (despite advertisements) are no substitute for pump-outs; they don’t make solids disappear! The Massachusetts Department of Environmental Protection does not recommend using septic system additives.

Reduce Water Use. Household water conservation will make your septic system last longer, and reduce your water and energy bills. Keep these tips in mind:

  • Repair leaking fixtures.
  • Replace that 5-gallon toilet with a modern low-flow model (the new ones get the job done and are surprisingly cheap).
  • Install a stylish low-flow showerhead (you won’t run out of hot water in the shower, anymore).
  • When you buy a new washing machine or dishwasher, insist on a model with the Energy Star Label.
  • Don’t let the water run during teeth-brushing, shaving or dishwashing.

Hold the Garbage! You can help your septic system get in shape by putting it on a low-solids diet. Here’s how you can send fewer solids down your drains:

  • Don’t use your toilet as a wastebasket.
  • Avoid using a a garbage disposal, or better yet, don’t install one at all.
  • Watch out for certain foods, like cooking grease, that are sure to cause your system heartburn. Since grease is difficult to break-down in a septic system, collect it in a can and keep it in the fridge instead of pouring it down the drain.

Don’t Sterilize It. Beneficial bacteria are one of the keys to a healthy septic system; anything you put down the drain that kills bacteria also harms your septic system.

  • Try to limit your use of harsh chemicals and antibacterial products such as bleach, ammonia and drain cleaners. For example, spot-clean mildew in the shower with bleach instead of cleaning the whole shower using a cleanser containing bleach.
  • Clear clogged drains with a plunger, boiling water, or a drain snake rather than with chemicals. In one study, less than 12 grams of drain cleaner killed the bacteria in a septic system!
  • Finally, never put paint, motor oil, pesticides or other household hazardous wastes down the drain. Bring them to your Town’s Hazardous Waste Collection Day.

Map It. Map the location of your holding tank and leaching field to prevent damage to your system. Knowing where your system is can help you avoid partaking in activities that can block, crush, or crack system components. Knowing where your system is will also save you money on pump-outs and inspections!

  • Don’t drive across your septic system.
  • Don’t pave or brick over it.
  • Don’t plant shrubs or trees above it.
  • Don’t dig into it (for things like swimming pools).
  • Don’t block access to the holding tank.

Why Maintain Your Septic System?

Save Money. Maintaining your septic system is much cheaper than replacing it or installing a sewer. Proper septic system maintenance – generally consisting of a pump-out every other year – works out to about $130 per year, or $260 every other year, for a typical 1,500-gallon tank, including pump-out and disposal.

Protect Water Quality. Sewage from failing septic systems pollutes ponds, streams and wetlands, choking them with mats of algae and aquatic vegetation, causing fish kills and making swimmers and fishermen sick.

  • Failing septic systems can also pollute drinking water wells that you and your neighbors depend on for tap water.

Be in compliance. Under Massachusetts law, your septic system must pass state inspection guidelines before you sell your home. Consider that with proper maintenance, your septic system could last up to 30 years. Without maintenance, it can fail in 5-10 years. While minor repairs on a well maintained system are often inexpensive, the cost of completely replacing your system can reach from $12,000 to as high as $55,000.

How a Septic System Can Fail: When Good Systems Go Bad

A common reason that septic systems fail:

  • A system hasn’t been pumped in a while
    • Excessive solids will build up in a holding tank and spill over into the leaching field and plug up the soil
  • When we dump solids or liquids faster than they can be treated
  • When the water table is too high because of flooding or heavy rains
  • When tree roots start growing into the leaching field pipes
  • When bacteria die-off due to chemicals
  • When there is a crack or obstruction in the system

You might have a septic system problem if you notice:

  • Sewage or wet spots on the ground above the leaching field
  • Gurgling or slow-draining indoor drains
  • Plumping or septic tank back-ups
  • Sewage odors in the house or yard
  • Persistent problems despite pump-outs
  • Test indicating bacteria in nearby well water, streams or ponds
  • Build-up of algae and other aquatic vegetation in local waterbodies

Please schedule an inspection if any of the above occurs!