What is considered a septic system or soakaway or drainfield failure? Are there failure criteria? Yes.
How Does Each Septic System Component Fail? What to Look For During a Septic Inspection - Step by Step Diagnosis of Septic System Failures, clogged drains, odors, sewer backup, wet areas in the yard, and slow drains.
This septic system inspection article describes detailed "how to" steps instructing the septic inspection investigator in how to inspect specific septic components for signs of failure.
We describe the criteria for saying a septic system has failed, and we take you step by step through the onsite waste disposal system, from the building to tank to absorption system, with suggestions for examining the condition of each component so that a proper diagnosis of the cause of septic failure and a specification of the appropriate repair can be made.
In the photo at the top of this page, a wet spot appeared in the previously "perfect" yard of this older home within twenty-four hours of the new family moving-in. The buyers had obtained a "septic inspection" but it was improperly performed and missed the chance to discover before purchase that the septic system was in total failure.
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Before digging up your septic tank or calling a septic pumper, if you think the septic system is failed because of drain blockage or drains backing up into the building, you should to see CLOGGED DRAIN DIAGNOSIS & REPAIR Is it a blocked drain or the septic system? - A First Step for Homeowners.
If you link to that text, please return here using your browser's "BACK" button.
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Any of the following signs might indicate that an onsite septic system has failed:
Watch out: we emphasized the word might indicate a septic failure because there are other possible causes of these conditions such as a blocked building drain or a broken sewage effluent box or blocked distribution box (D-box).
Watch out: also there are other more technical septic system failures that require major repair or even re-design but that may not be immediately obvious, such as a failed septic drainfield or mound whose effluent is being discharged to a more-distant point not immediately obviously connected to the septic system, such as into a nearby drainage ditch, lake, or stream.
Another example of a "failed" septic system is really one that was improperly-designed or improperly-constructed in the first place, such as a septic drainfield or mound at which the bottom of the effluent distribution trenches is not sufficiently above the seasonal high-water table in the area (typically two feet).
If a septic system backs up, floods, or fails in wet weather it may be improperly designed, or it might be possible to correct the problem by better management of site surface and subsurface runoff control.
At RECOMMENDED ARTICLES we provide additional guides to detailed inspection procedures telling you where and how to look for and diagnose a septic system failure.
Definition of a septic system "failure": a septic system is considered in failure or to have failed if one of or more of the signs or conditions listed below are present.
Massachusetts Title 5 Septic Law lists specific failure criteria and serves as a good model for septic inspections anywhere.
(The photograph shows the septic baffles in a concrete septic tank. While at the time of inspection the sewage was not flowing over the baffles, sewage debris atop the concrete baffle shows that at some point that problem had occurred. Further diagnosis was in order.
Detailed criteria that define when a septic system has failed can be read
Outside, waste piping conducts sewage (black water and gray water) from the building to the treatment tank or "septic tank," and from the treatment tank to the distribution box.
Our photo shows a new waste line carrying sewage down from the home to the septic tank in lower yard. The previous waste line had been broken when driven over by a heavy lawnmower.
Septic drain lines between the house and the septic tank should be of solid, non-perforated material and need to be protected from mechanical damage (such as by vehicles).
Piping extending from the distribution box into drain fields is normally perforated, though solid lines might be used if effluent is being processed by more specialized devices such as seepage pits, galleys, or a sand-bed system.
Distribution piping connects the house drain to the septic tank, running between the building and the tank inlet.
More distribution piping connects the septic tank outlet to the distribution box and from there to the leach field. Distribution pipes can settle (especially in new construction), break, become blocked or clogged, or become invaded and blocked by tree roots or soils.
Older ORANGEBURG PIPE [web article] which look like black asphalt-soaked cardboard (they are) crush and deteriorate with age.
Clay pipes also break and have a tendency to become blocked by tree roots at their joints. You won't know what kind of piping is installed until it is excavated, but the age of the property may be a clue. Homes built from the 1970's on, certainly from the 1980's on, use cast iron or more often plastic ABS or PVC piping for these connections.
This line may become blocked by waste, damaged by collapse of a section, or invaded by roots. Detection of these conditions is fairly easy by routing a snake or power snake from the building drain to the septic tank.
An experienced power snake operator can often tell by "feel" that a drain line is collapsed, partially collapsed, or invaded by roots. While you may make a temporary "repair" of such a condition by drain-cleaning, if the line is broken or root-invaded, you should expect to have to excavate and replace it soon.
Also see DRIVING or PARKING OVER SEPTIC
The same failures can occur on the effluent distribution pipe line from the septic tank outlet in to the distribution box as we described earlier on piping from house to the septic tank.
Pipes can settle (especially in new construction), break, become blocked or clogged, or become invaded and blocked by tree roots or soils.
How would we distinguish among blockages at different points in these distribution lines?
Distribution boxes serve as a connection point to distribute effluent which arrives from the septic tank outlet and is to be sent into two or more individual leach field lines.
Distribution boxes ("D-Boxes") can settle or tip.
A damaged or tipped D-box will fail to divert effluent uniformly among the effluent receiving drainfield lines, causing flooding of one leach line. If you see depressions suggesting that there are four leach lines at the property and the end of just one of them is producing wet soil or surface-breakout of effluent, we'd suspect a tipped D-box.
Opening the D-box can also show whether or not effluent is being directed uniformly into each of the leach lines. A tipped D-box can overload one line and cause early failure of the absorption system.
If this is happening, flow adjustment end-caps (eccentric holes) can be installed in the distribution box on the inlet end of each of the drain lines, permitting adjustment of effluent delivery into each line, perhaps relieving the problem line and redistributing effluent into the others.
In a conventional "drain field" (synonyms: leachfield, leaching bed, soakbed, soakaway bed, seepage bed) of perforated pipes buried in gravel-filled trenches, a drain line may be invaded by tree roots. This is why experts advise keeping tree and shrub plantings away from drain fields.
Vehicle traffic can also collapse this or any outdoor waste piping, which is why experts advise against ever driving over a drainfield or over any other septic system components.
See DRIVING or PARKING OVER SEPTIC
Drainfield piping is usually constructed of perforated pipe buried in gravel-filled trenches. It receives effluent from the D-box and allows it to percolate or seep into the soil around the trench where added filtering and bacterial treatment occur.
Like the distribution piping discussed above, individual drainfield pipes can become crushed, shifted, or clogged by tree roots or other debris. More general clogging and failures of the leach field are discussed below.
A broken or clogged pipe, once it has been located, may be much less costly to repair than a complete leach field replacement, so this possibility needs to be considered during diagnosis of a "failed" septic system.
Lockwood, in "An Engineer's View of Septic Systems" listed these causes of absorption field failure:
" If the liquid effluent cannot soak into the soil surrounding the leach field, sewage may back up into the system and overflow into the house or puddle on the surface of the ground. There are several possible causes for this problem."
...
Below you will find questions and answers previously posted on this page at its page bottom reader comment box.
Is this backing-up toilet a sign of a septic failure?
New tenant experiencing this - we just had septic drained, is this sewage backflow? Is it indicative of leach field problems? On 2021-07-22 by backupbackup7489
Reply by mod) - sewage rising in toilet: is this sewage back-flow
@backupbackup7489,
yes and yesor a blocked sewer line or main drain
50 year old septic system has sewage coming to the ground surface: what's wrong?
We have a tank and field, installed 50 yrs. ago We have sewage coming up to the surface, wondering what the problem could be? On 2020-11-26 by Cliff Leschyshyn
Reply by (mod) -
ON a 50 year old drainfield it'd be no surprise if the soil no longer absorbs effluent, having become blocked by a thickened biofilm layer;
if that's the case it's time for a new drainfield.
If a logging truck crused or broke my septic field pipes how soon will we see trouble?
If my field lines had been crushed or broken by a logging truck how soon would I notice a field problem? - On 2020-11-11
by Sharon
Reply by (mod) - it depends on extent of damage, soil conditions, and septic system use
Sharon
That's a great question, but I don't know a clear answer to how long before a septic failure will show up if a septic drainfield line is crushed.
Here are two different cases that illustrate what can happen.
1. Immediate to 48 hours until septic trouble shows:
A vehicle drives over a drainfield and crushes or breaks one or more effluent lines: wastewater backs up in the septic tank and floods the building OR there is a new breakout of effluent at the ground surface in or near the area of damage.The problem is evident almost immediately, certainly within a day or two as hundreds of gallons of wastewater enter the septic tank and push a like volume of effluent out into the drainfield.
This situation assumes that the septic system design is a conventional one and that the septic system is in use at typical levels of hundreds of gallons of wastewater per day.
2. Damage does not show up for years:
A vehicle drives over a drainfield and crushes or breaks one or more but not all of the effluent disposal lines: damage is near the end or damage does not affect all of the drainfield lines.
The damage may not appear as a septic system backup into the building nor may effluent appear at the surface for years. Instead, the effect of this damage is rather to reduce the total available drainfield area for effluent disposal.
The result may be not an immediate failure, but rather a reduced life of the septic field.The damage may never become evident or it may become evident only if/when one or more of the old drainfield lines is excavated.
Additional variables confound the "when will septic damage show up?" question, such as soil conditions, total drainfield size, level of septic system use, weather conditions, wet or frozen weather affecting soil's ability to absorb effluent, terrain shape, level vs. sloped, rocky vs. uniform soil, and other similar factors. Septic system type and design are also critical in answering your question.
For example driving over a septic mound or raised bed or sand bed septic is likely to cause damage to show up very quickly, often as effluent breakout lower on the mound or raised bed or near its perimeter.
ur Enviro system septic has failed and we don't recommend this system
I'm writing to let everyone know that our Enviro system has failed in 2020 and do not recommend using this system. Buyer beware.
The plan was drawn up in 2009. We moved into our newly built home in 2011. We pumped the tank every 2 years - that's 4 times starting in 2013. The designer/surveyor that was used has done a new design gratis. Here is where it gets interesting.
The new plan is 50% larger than the original plan following the same specs of a 5 bedroom plan for our 4 bedroom home. We over built our system for our own security for it to last. I believe Presby had overestimated the quality of their product back in 2009.
The information used from Presby is sent to the state for designers to follow the specifications. At the time of our build vents were not required. The installer and designer followed those specifications and didn't have them as part of the design.
The original installer is now putting in a new field gratis, because like the designer he feels the product is inferior. In contacting Presby, they have not offered anything up other than the tech to check out our system and point fingers at others. He confirmed all the tubes where full of fluid.
Which means the had not been crushed by any outside source. He confirmed the proper sand was used but not enough of it surrounding the tubes. The designer and installer say that the sand could have moved because of the flow. Town inspector and a third party inspector who called our leach field failed feel, that the homeowners are not at fault. The pumping company are surprised we are failed. - On 2020-10-27 by Susan - O
Reply by (mod) - get an accurate diagnosis of the cause of failure of your Enviro septic system
Susan
Thank you for the report on trouble with your Enviro Septic system.
It will be helpful to get as clear a diagnosis of exactly what failed and why as possible, both to minimize the chance of blaming the wrong cause and to minimize the chances of having to install a septic system over and over again because we didn't know what we were doing "wrong".
"the product is inferior" is, unfortunately, just too vague a diagnosis for me to make much out of it.
When "the tubes are full of fluid" that does NOT mean that there was no damage to the fields from an outside source.
Even if a septic effluent absorption system's piping is not itself "crushed" or visibly broken or dislocated - something to discover by a thorough inspection by sewer line camera - that does NOT tell us that there was no external damage to the system. For example if during or after construction someone drove heavy equipment over a field so as to compress the soil that can cause a field failure;
Similarly, construction of a septic field too low - too close to seasonal high water table, or failure to direct surface and subsurface runoff away from the area will guarantee that a field will have a short, ineffective use.
"Not enough sand around the tubes" - if you're referring to how perforated piping was installed in trenches to allow soil to absorb septic effluent - could be only the tip of the iceberg of frosty failure.A lot - almost everything - depends on the type and amount of soil available to accept effluent and to host bacteria (aerobic and anaerobic) who are needed to process and digest the pathogens in the effluent. So if the soil can't accept effluent or is flooded, even just sometimes, the system won't work.
That sort of installation snafu would have little to do with "the product" and almost everything to do with "the installation".
The installation needs to follow the specifications of a professional design that was in turn set out based on a survey of the site: available space, soil perc rate, elevations, slopes, and required size based on anticipated daily wastewater flow.
So see if you can get details.
How do I know where the septic entrance is?
how do I know where the entrance is? 2020-10-10 by Rochelle K Ibanez
Reply by (mod) -
Rochelle
What entrance are we looking for?
SEPTIC DRAINFIELD LOCATION inspectapedia.com/septic/Septic_Drainfield_Location.php
FIND the SEPTIC TANK, HOW TO - inspectapedia.com/septic/Septic_Tank_Find.php
SEPTIC D-BOX LOCATION inspectapedia.com/septic/Septic_D-Box.php#Find
If by "cap off" you mean trying to empty or clean a septic tank by pumping it out through a small 6-8" diameter access opening, it's possible to pump the liquid and a very limited amount of the solid scum and sludge through a small opening but it is in my experience and opinion impossible to actually clean a septic tank through such a small opening.
To remove all or even most of the settled sludge and floating scum in a septic tank the pumping technician needs to be able to manipulate the pumper hose across all of the septic tank interior and often to use a hoe-like tool to break up scum and sludge to pump it out of the tank.
It's also not possible to determine the condition of the septic tank and its inlet and outlet baffles thorough such a limited access opening.
On 2020-10-10 by Rochelle
Can a tank be emptied at the cap off? We cwmwnted part of our yard. The cap off is in the grass at back of yard.
On 2020-09-24 by Ron
I have a septic tank that has never been pumped (33 years). Over the last year there has been a settlement of soil around one edge of the tank. I have tried to top fill with dirt but the settling keeps happening. There are no signs of standing water, backed up drains or odors.
Any advice?
On 2020-09-24 - by (mod) -
Ron
When a septic tank has not been pumped in 33 years you are far past the expected life both tank and drain fieldYou need a septic contractor to open the tank and inspect his condition. It's quite possible that the tank is leaking and there is causing soil subsidence. Keep in mind that it's likely that your drainfield is also an end of life
Septic failed 6 weeks after tank was pumped. Now what?
Our septic had one occurrence of overflow only 6 weeks after a clean out. What advice can you provide. On 2020-08-03
by Al Johnstone
Reply by (mod)
Your septic system is in failure - but we don't know if the problem is a broken pipe or a failed drainfield, so we need an on-site expert septic inspection and test. Just cleaning out the septic tank won't prevent nor cure failure or backup of an already-failed septic.
On 2020-07-10 by Joe
Hello. I have found your site very helpful. I have a question regarding why my septic system was "failed" and expensive corrections suggested. This was the information provided as to why the septic system failed. (No prior issues. System was due for pumping. Visual inspection was done at time of pumping. 1,000 gallon capacity)
"However, the scum line was not at the appropriate level and waste was found on the
septic lid and in the build-up. This is an indication of drainage failure and should be
evaluated further."
On 2020-07-10 - by (mod) -
Joe
I agree that that's a pretty marginal "report".
If the liquid (not just scum) level was above the bottom of the outlet pipe from the septic tank then we could be facing a failed drainfield but we could be lucky and find a blockage or a tipped distribution box.
So before agreeing to any costly repair let's get a more thorough and expert diagnosis.
Start by finding the D box and using a sewer cam to check the lines.On 2020-07-10 by Joe
I'll do just that. Thank you!
I’m not sure if you will be able to help us or not. But we live in Ontario Canada.
We had our 45 year old septic completely redone in July 2019. And in April 2020 we noticed that it wasn’t working and backed up around the lid.
So the company came again and redid part of the septic and it did the same thing.
So they came in May and did a completely new septic and it has only been 3 weeks and already it is starting to fill past the filter/distribution drain.
Not only is this completely worrisome and stressful but the hours of back breaking landscaping we have had to do to get our place back in order are countless.
We are at a loss and have co tatted the company. We are waiting for a response. I’m just wondering if you can give us any ideas moving forward.
We don’t know who else to contact and we also don’t feel we should have to pay for this.
This is after just 3 weeks - Anonymous by private email 2020/06/15
Moderator reply:
about
... it has only been 3 weeks and already it is starting to fill past the filter/distribution drain. ...
I don't understand the phrasing. Are you describing the level of sewage in the tank or something else? It's normal for a septic tank to be "full" with liquid effluent reaching the bottom of the outlet pipe, and for effluent to flow out to a drainfield.
Want to update us?
Reader follow-up:
It was draining perfectly from the house and then we had a very heavy rain and both tanks filled, past the outlet pipe.
And it has not gone back down.
Our guy says for some reason the ground is holding water.
We are having our yard dig up for the fourth time in a year next week.
It’s beyond stressful and we constantly worry that it will back up into our house.Do you have any suggestions?
Moderator reply: "ground holding water" does not describe an acceptable nor working septic drainfield system
I'm not sure what to make of the ground holding water argument but in general if a septic drain field floods or if water leaks into the septic tank in rainy weather then there's a problem to be found and fixed.
Sometimes we can simply direct surface runoff away from the flooding septic tank. What's needed is a closer inspection to see where water is getting into the system.
It could be at the septic tank, at a piping connection, at a septic tank cover or clean out access, or it could be downstream if the drain field is flooding and back flowing into the septic.
That last case is the most serious in terms of difficulty and expense to correct the problem.
A diagnostic of a flooded or failed drainfield might be as simple as watching the septic tank during pumpout; if, as the sewage level falls below the septic tank outlet, we see or hear liquid spilling back into the septic tank from its outlet pipe then the pipe or drainfield is / are, blocked or flooded or not working properly.
On 2020-05-21 by Autumn M Noonan
We discovered an area of bubbly water that comes out of our ground during the day when we using water laundry ECT. and then dries up at night. And my landlord won't do anything about that is that okay? I'm on County Land he said it will be expensive to fix and he wants to give it a week to see if it dries up. For once I just like a good landlord any takers
On 2020-05-22 - by (mod) -
Autumn,
Discharge of waste water to the ground surface is improper, indicates a failed septic system, and is illegal in most jurisdictions.
On 2020-02-22 - by (mod) -
Natslie
Possibly,
It depends on where the line was damaged.
For example if you damaged and blocked the main effluent line out of the septic tank head of the distribution then you'd block the tank outlet.
On 2020-02-22 by Natalie
Could three fence posts put in leach field ( they DID puncture the plastic) cause the tank to not drain at all?
On 2019-10-03 - by (mod) -
Carolyn
I really wish I could be more helpful but I just don't know a thing about your site or its condition. YOu need an onsite inspection.
On 2019-09-30 by Carolyn Muldowney
Where my drain field is, the spot in the yard seems depressed. No standing water. Did notice an odor but din’r Know if it’s mune or a neighbors. Should I be concerned? I take very good care of my septic system
On 2019-09-30 - by (mod) -
Dean
Where is the septic tank riser that's leaking - in the piping scheme for the septic? If it's between house and D-box and effluent is backing up there and the D_box is dry then the line is probably blocked between the riser / access pipe and the D-box
On 2019-09-29 by Dean hammons
Riser leaking but no water in distribution box
On 2019-07-03 (mod) - Nostock commune fungus growing in septic leach field area
GKW about Nostock commune - that you have identified as an algae-like cyanobacteria that looks like animal poop but is not,
Please see our discussion all collected along with more information now found at
SOAKBED SOIL CONDITIONS
On 2019-06-22 by gkw1944
I have been finding this unusual material on my leach field. Black curdled plastic/rubber stuff. It has no smell and does not appear to be waste.
I called several septic companies no one responds. Should I call a plumber instead?
On 2013-03-23 - by (mod) -
Dee
YOu should not be seeing solid waste in the drainfield. If you do then I figure your septic tank may be missing an outlet baffle and it is sending solids into the drainage area - which, if that's the case, will damage it and shorten its life.
On 2013-03-22 by dee05
we have a new drain field but waste and tise is just sitting their in a hard block when my husband open drain field and now its backing up in my house
On 2013-03-18 - by (mod) -
Lynn,
If water is backing up in the basement that ought to be enough evidence to insist that the problem must be repaired promptly; there are serious possible health hazards from sewage, bacteria, and mold.
I don't know why you'd be testing for ammonia.
BUt if you want to take a sterile bottle of "basement water" to a local testing lab they can certainly tell you the sewage level in the water.
On 2013-03-18 by Lynn Johnson
Great information from your website. I think I am dealing with a septic failure in my moms home but she is not facing reality. Water is backing up inthe basement. Short of contacting the health department, is there a test to do prove that a house has septic gases in it fromwater backup? I know you can do a test for amonia levels, but I am wondering if there is a simple tool that can read the air quality for a home.
thanks
On 2012-12-04 - by (mod) -
Tim,
In at least some installations, if the end of a leach line is uncapped effluent will, especially under heavy usage, just run out of the end of the line onto the ground surface - improper and in some jurisdictions, illegal as you're discharging wastewater to the ground surface.
More interesting is what it means if an end of a leach line is not capped and you do not see efflent running out - I'd surmise that either wastewater usage was very low, the drainfield was enormous, or that there was a blockage upstream and that line section was not taking effluent. In that case I'd start checking at the D-box and maybe at an earlier location along the line.
On 2012-12-04 by Tim
What happens if the end of a leach field line is not capped? Does the system still function?
On 2012-10-17 - by (mod) -
Christine,
If yoursnis an old rusted steel tank it is likely not repairable and needs replacement. Concrete or plastic tanks can be repaired by a professional.
DO NOT EVER attempt septic tank repair yourself. Entering a septic tank without expert training, equipment, and assistance will likely be immediately fatal.
On 2012-10-15 by Christine
If the inspector says my septic tank has a leak because the water inside tank will not remain at operating level (about amonth after tank was pumped), what are my options to fix? Can the tank be lined, the crack sealed or must the whole tank be replaced?
On 2012-09-16 - by (mod) -
Mary,
I think the first priority is to make the tank you found safe - to avoid an injury or worse, a fatal accident of someone falling into it. That means filling the abandoned tank with sand, gravel, soil. Some operators break open the tank bottom before that operation;
Beyond that specific project, you can locate other buried site components by a combination of examining likely locations visually, using a metal detector (obviously only useful for steel tanks), by finding and snaking or trying to trace sewer piping.
Detailed suggstions for finding tanks, cesspools, etc. are in a separate article found in the ARTICLE INDEX and titled
SEPTIC TANK, HOW TO FIND
On 2012-09-14 by Mary
We have just discovered an abandoned concrete septic tank. Our house was built in 1953. How do I determine if I have a leach field or a cesspool/drywell. I'm concerned about the possibility of a cesspool or drywell.
...
Continue reading at SEPTIC FAILURE SPOTS - where to look, or select a topic from the closely-related articles below, or see the complete ARTICLE INDEX.
Or see SEPTIC FAILURE INDICATOR FAQs - posted originally at this article
Or see these
SEPTIC FAILURE SIGNS at InspectApedia.com - online encyclopedia of building & environmental inspection, testing, diagnosis, repair, & problem prevention advice.
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