Take Care of It and It Will Take Care of You
When a septic system is working properly, few people give it much thought. Like most of your home’s mechanical systems, it’s usually out of sight, out of mind – until it breaks. When a septic system fails, however, it quickly becomes a crisis. Functioning indoor plumbing is essential to modern life.
The solution to a failed septic system is usually to excavate and replace some or all of the components. The cost can range from a few thousand dollars to well over $10,000. The good news is that you can delay that date by years or decades by taking the simple steps required for septic system maintenance and care.
You may get away with ignoring your system for a long time. Light usage, good soil conditions, and luck might be on your side. But sooner or later, you’ll face poor performance, premature failure, and a big bill. The good news is that keeping your septic system healthy is easy and inexpensive.
Even if you have purchased a home with an existing system that has been poorly maintained, your efforts will pay out in extending the life of the system. Think of it like your car – you can save a few dollars each year by not changing your oil — but may have to buy a new engine when it dies.
In most cases, a septic system failure is a result of the leach field (drain field) that can no longer adequately process the effluent. A failed system is not pretty thing. And since failure often happens gradually, people sometimes delay repairs until the situation is intolerable. Depending on the extent of the problem, you may experience these symptoms:
- Slow, gurgling, or backed-up drains
- Mushy ground or puddles over the leach field with septic odors
- The need for frequent pumping
- High nitrate levels in your well water
- In extreme cases, pathogens or toxins in your well water
- Early replacement of the leach field
If you’re ever lived with a failed or failing system, you know the routine – slow drains, frequent pumping, and unpleasant odors. Since a failed system is not fully breaking down the effluent, it can lead to pollution of the groundwater, including surface water and well water.
The first sign of well-water contamination from septic discharge is usually rising nitrate levels. Nitrates are considered a marker for untreated effluent, which can introduce bacteria and other pathogens. Also, excessive nitrates can lead to have been associated with their own health risks, especially to infants.
While no leach field will last forever, you can extend its useful life by decades by reducing household water usage, paying attention to what goes down the drain, and having your system inspected and pumped on a regular basis.
Changing your household habits costs nothing, and getting your system inspected typically costs $100 to $200. Pumping typically costs $200-$300. Replacing the leach field, on the other hand, will often costs from $3,000 to over $10,000 depending on site conditions and regulatory issues. If there is no space for a replacement field, you will need to dig up and replace in the same spot, a more expensive and complicated procedure.
Once you switch to your replacement field, the original drain field will have time to naturally clear itself out and, assuming it has not been damaged or compressed by traffic or heavy equipment, should be available to use in the future.
Upgrade required. When you go to replace the leach field, or leach pits, you may discover that the septic system regulations have changed in your area, and that you are required to put in a more expensive system to comply with current codes. This is yet another reason to keep your current system in good health. You never know what hoops you’ll need to jump through, and checks you’ll need to write, to repair or replace your current system.
Alternative Systems. If you have an alternative septic system, the maintenance needs are greater and the cost of repair or replacement is often much larger. In general, these systems are more sensitive to misuse and much more expensive to repair or replace. Most have pumps, controls, alarms, and other mechanical components that are subject to failure. More frequent pumping is required.
If you have an alternative system, educate yourself about how it works and pay extra attention to its maintenance needs. A service contract that includes annual inspection and maintenance is a good idea, and is required in some areas as a condition of the permit.
Fortunately, septic system care and maintenance is really pretty simple and inexpensive. There are four main components:
- Avoid excess water. Minimize water flow into the system from household plumbing. Also direct outside water away from the drain field.
- Don’t flush chemicals, grease, trash. Don’t put chemicals, paints, food scraps, grease, or other solids down the drain.
- Don’t compress the soil. Protect the drain field from damage. Don’t drive, park, or build over the drain field. Plant grass and keep trees a safe distance.
- Inspect and pump. Annual inspection is a good idea. Your pumping schedule depends on the tank size and usage.
Below, we’ll discuss each of these maintenance strategies in more detail and how they help keep your system healthy and prolong it’s life.
According to the EPA, the average U.S. household uses about 70 gallons of water per day per person, most of which goes down the drain. You system is designed based on the number of bedrooms (assuming two people per bedroom) and an average flow rate, spread out over the day. Over time, the system capacity can be reduced as the soil around the drainage trenches gets clogged.
Putting excess water into your drain field will keep the soil saturated and unable to absorb incoming wastewater. Also, over time, a saturated field will develop a thick bacterial “biomat” that blocks the normal flow of water into the trenches. While some biomat formation is normal and necessary to help treat the effluent, a thick mat that covers the entire trench bottom will cause backups and system failure.
Also draining large quantities of water into the system can overfill the tank, forcing solids into the the drain field and clogging the soil. Wastewater should sit in the tank for about 24 hours for solids to settle out.that have not had time to settle out.
Overuse of water is the most common cause of failed systems, making water conservation a top priority. Federal laws now require all new toilets and fixtures to meet low-flow standards.
Water conserving toilets. Toilets account for the largest share of household water usage, so replacing old models is an important first step. Most toilets installed before 1994 use 3.5 or more gallons per flush vs. 1.6 gallon models in new models.
Faucets and showerheads. Modern low-flow shower heads reduce flow from 5 -8 gpm to no more than 2.5 gpm for showers and 2.2 for faucets. Today’s low-flow shower heads can produce a nice shower spray, a big improvement over earlier models.
Turn off faucets. When washing up, brushing your teeth, or doing dishes, avoid running the water more than necessary.
Space out laundry loads. Running four full loads of laundry on laundry day can flood the field and overfill the tank, forcing untreated wastewater (with solids) into the leach field, clogging the field. Best to space out loads and use a water-conserving model.
Water treatment. If possible, don’t send backwash from your water softener or water-treatment system into your septic system. If you must, route the drain directly to the distribution box, avoiding the septic tank. Studies have shown that putting 30-100 gallons of backwash brine into your tank washes solids downstream and interferes with normal tank functions. There is also evidence that saltwater promotes clogging of the leach lines.
Yard and roof drainage. Don’t put your drain field in a low area that collects water. Direct water from downspouts and yard areas, sump pumps, and foundation drains away from the septic tank and drain field. Excess water seeping into the ground has the same effect as excess water from the house – a saturated drain field that functions poorly and may fail early.
The short and simple answer is to only put down the drain water, human waste, and toilet paper – nothing else! Here’s why:
Fat, grease, and cooking oils are lighter than water, so they float to the top of the septic tank as scum. This is removed when the tank is pumped, but excess scum or heavy water usage can drive this material into the leach field, where it will contribute to clogging and premature failure.
Chemicals, solvents, bleach, and paints. Most normal household soaps and detergents are fine to use. Harsh chemicals, drain cleaners, solvents such as paint thinner, and oil-based paints are poisons that could contaminate your groundwater. Bleach, pesticides, anti-bacterial products, and other chemicals can kill the friendly bacteria who are working for you breaking down the effluent.
Food scraps. Most septic systems are not designed to use with disposals. Food scraps contribute unwanted grease and solids. If too many solids collect in the tank, they will end up clogging your drain field. If you have a disposal, use it minimally.
Everything else. Your septic system is not a trash can or landfill, so don’t treat it like one. No cigarette butts, tampons, kitty litter, leftover drugs, or anything else. Most toilet paper, white or colored, is fine, but avoid paper towels and tissues, such as Kleenex, which are meant to stay together when wet. At best, these clog the system and increase the need for pumping. At worst, they can block or damage system components.
The best ground cover for the leach field is grass, which helps the system reduce excess water through evaporation. And as they say, “The grass is always greener over the septic system” due to the plentiful moisture and natural fertilizer. Avoid wood chips, mulch, Astroturf, or other non-plant coverings.
Compression of the soil will impede its natural drainage and potentially move or damage the piping. It will also interfere with oxygen reaching the leach pits. So don’t drive, park, or use heavy equipment over the leach field, septic tank, or the piping from and distribution box.
Also, don’t place a deck, patio, or any other construction over the tank, drain field, or other components. You risk compressing the soil, damaging the equipment, or interfering with inspections and maintenance. Also, if the partially treated water ever surfaces with its distinctive odor, you will regret trying to use the space creatively.
Finally, keep large trees away from the drain field as roots will seek out the water in the drains and block the flow. Many popular tree species are known to have invasive roots. These include willow, magnolia, poplar, birch, and oak. An arborist can help you decide what is safe to plant and a reasonable clearance.
Annual inspections are a good idea, but you can probably stretch this out with a lightly used system. In the typical inspection, they uncover the tank and measure the scum and sludge layers. If either is too thick, they will recommend pumping. In addition, they will
- check water flow from toilet to tank
- look for cracks or other damage to the tank
- check the baffles or tees in the tank
- check the distribution box or pump station (in a pumped system)
Some common rules of thumb are that the sludge layer should not exceed one-third of the liquid depth or be within 12 inches of the outlet pipe. The bottom of the sludge layer should be at least 3 inches above the bottom of the outlet baffle.
In a more thorough inspection, they may locate the drain field pipes with a long soil probe and use a soil auger to take soil samples at the bottom of the trenches, examining the soil conditions and thickness of the biomat. In some cases, brightly colored dyes are added to the wastewater to diagnose blockages or leaks in the underground system.
In any case, do not wait until there are problems, such as slow drains or backups, before pumping. By that time you have already sent grease and solids into the leach field, impaired its functioning, and shortened the life of your system.
The following pumping chart is published by the National Small Flows Clearinghouse, which is funded by the U.S. EPA. The NSFC provides great information about on-site sewage systems.
Septic systems usually fail gradually as the soil around the drain field trenches gets clogged over time with solids, and a thick, slimy “biomat” blocks wastewater from reaching the soil.
Since the soil can no longer absorb wastewater fast enough, it backs up from the drain field to the septic tank. Drains will empty slowly and sewage may start to back up on basement or first floor fixtures.
Backups can also be caused by blockages, breaks, or movements in drainage pipes that interfere with normal drainage.
There are various “miracle” additives on the market which promise to improve septic system performance, but there is little evidence that they do any good.
Hydro-jetting. Also, there are also contractors who will attempt to restore your failed system. The most common approach is “jetting” pressurized water and air into the drain field to break up and aerate the compacted and clogged soil around the leach lines.’
If done properly, jetting may be able to buy you some time. If done poorly, it can move around underground components, breaking connections, and making things worse. Even if done well, this is at best a short-term fix that might not be economical in the long run. If you need to go this route as a short-term solution, look for a company that backs up its work with an iron-clad warranty. And check references!
As with much in life, the best and cheapest treatment for septic system problems is prevention. Compared with many things in life, maintaining a healthy septic system is easy. You don’t have to pump iron and jog five days a week. You do, however, have to pump out your septic tank regularly, watch what you flush down the drain, and avoid damaging your drain field.