Septic tank flooding or back flooding: definition, diagnosis & repair procedures are explained here.

What causes flooded septic tanks or abnormally-high sewage levels in septic tanks and what do we do about it? A flooded septic tank can cause a sewage backup in a building or ejector pump flooding.

Backflooding means that water or wastewater is flowing backwards into the septic tank from a soakbed or drainfield or from surface runoff.

To understand how to fix the problem of high waste levels in a septic tank we need to diagnose the cause, then outline, in order from least costly to more expensive, the approaches to fixing this problem.

Here we explain back-flooded septic tanks & an understanding of how to diagnose abnormal septic tank sewage levels can tell us what septic system repairs are needed. Do we just need to seal a pipe connection, clear a clogged sewer line, or do we need to control surface runoff, fix septic tank leaks, or replace a failed septic soak-bed?

Septic Tank Flooding & Back-Flooding: Why it is important to diagnose & fix water leaking into the septic tank

This article discusses the problem of ground-water, surface runoff, or septic effluent flowing into the septic tank - a condition we call "septic tank back-flooding". This can happen under any weather conditions and is not restricted to times of area flooding.

Watch out: if your septic tank or septic system has been exposed to area flooding you should see the immediate safety steps given

at FLOODED SEPTIC SYSTEMS, REPAIR - keep people away from the septic system and turn off electrical power to its components.

How to Diagnose a Flooded Septic Tank - a common cause of building sewage backups

While I agree that we would expect a relatively new septic tank to be un-damaged, it makes sense to actually inspect the tank so that we don't waste time with a lot of arm-waving speculation when a little bit of digging and looking can go a long way towards sorting out the problem.

Definition of Flooded Septic Tank: a septic tank in which the wastewater level is above the bottom of the septic tank outlet pipe's bottom-most surface is flooded, not working properly, and inviting a sewage backup into the building.

Note: here we are discussing septic tanks flooded by system construction, maintenance, site drainage control or other errors, or by a failed drainfield. Separately

at FLOODED SEPTIC SYSTEMS, REPAIR we discuss what to do when a septic system has been flooded due to area flooding from a hurricane or other storm causing high floodwaters.

Normal and abnormal septic tank sewage levels are explained

at SEPTIC TANK LEVELS of SEWAGE.

When the septic tank level is abnormally high we need to determine why, as knowing the cause defines the necessary repair.

In simple terms the septic tank wastewater level may be abnormally high because

1. The septic tank outlet is blocked from one of several causes we'll detail below, such as a clogged pipe or a failed drainfield
2. Water is leaking into the septic tank from surface or subsurface runoff at one of several possible leak points we will discuss below.
3. The septic tank is back-flooding from one of several causes we'll detail below.

Definition of Septic Tank Back-Flooding: a septic tank that is suffering back-flooding is one into which wastewater can be observed entering the septic tank at its outlet end or outlet effluent pipe as the septic tank is being pumped or emptied.

A partially-full septic tank may still be considered flooded if it is filling too quickly

Watch out: a septic tank may also be technically flooded even if the total level of wastewater is below the septic tank outlet. How the heck could that be? We encountered just this condition at a home recently.

The septic pumping company reported having completely emptied the septic tank during a period of wet soils and lots of surface runoff due to snow-melt.

A day later the building basement suffered a flood that owners correctly believed was due to surface runoff and snow melt leaking into the building. But in the course of diagnosing that condition the septic contractor returned to the home to inspect the septic tank liquid level again.

In a day after a (reportedly) 1,500 gallon septic tank had been pumped "empty" according to the contractor the tank was by his estimate 85% "full" again. The home, occupied by a single older resident, certainly had not produced 3/4 of a septic tank's worth of wastewater in a day.

As the owners believe there was no wastewater being produced by running toilets nor other water-dispensing equipment, it was evident that surface runoff and snow-melt that were flooding the home's basement were probably also the source of water entering the septic tank. Further diagnosis was needed to determine if the septic tank flooding was due to leaks into the tank or due to a failed drainfield that was also saturated by snow-melt

Relationship of Septic Tank Baffles to Septic Tank Flooding

The tank baffle condition does not itself immediately cause a septic tank to flood or not.

Watch out: A broken or missing septic tank baffle on the tank inlet side invites sewer line clogs between building and tank and building sewage backups; a broken or missing septic tank baffle on the outlet end of the septic tank means we're pushing solids into the drainfield or soakaway bed, basically destroying that expensive component by clogging the soil around the drainfield trenches with solid waste, grease, scum, etc.

Details about septic tank baffle inspection and repair are at

SEPTIC TANK BAFFLES.

There we explain that by inspecting the septic tank sewage level prior to pumping the septic contractor can see if the waste level is abnormally high (over the baffles - a flooded septic tank) or abnormally low (a leaky septic tank if the tank has been in use long enough that it should be full).

 

Open & Inspect Septic Tank Inlet & Outlet to Diagnose Tank Flooding

By opening the tank at its inlet and outlet ends, exposing the septic tank baffles and pipe connections, and inspecting with some thought, particularly if we make observations while having the septic tank pumped, we can see where water is coming in and thus know what needs to be done next.

• If we see sewage marks over the top of the tank baffles we know the tank has been flooding.
• If we see sewage wastewater that is above the bottom of the septic tank outlet pipe then the septic tank is flooded even if waste is not actually over the baffle tops.

• If we see waste water entering the septic tank at its inlet: With all water turned off at the building and nobody flushing toilets, we should not see water entering the septic tank at its inlet connection to the building sewer piping.
  
  
  • Groundwater leaks into the septic tank at its inlet pipe connection: If we do see water entering the tank when it's not coming from the building drain system, there may be groundwater leaks at the pipe-to-tank connection itself where the sewer pipe enters the septic tank or there is a different septic tank leak point (listed below).
    
    A poorly-sealed sewer line connecting the building sewer drain to the septic tank often causes leaks into a septic tank.
    
    The trench originally cut to run the sewer line between building and septic tank forms a natural surface or subsurface water catchments or intercept that, because it slopes towards the septic tank, also delivers all of that water to the septic tank connection.
    
    We repair this by sealing the connection and/or by excavating a diverter trench to send trench water away from the septic tank to a downslope location (not onto the drainfield).
    
    In our photo at above left we had a sewer line making a steep downhill plunge towards the septic tank inlet end.
    
    The trench ran at a slight diagonal across the hillside, making a very effective water catchment that sent all of that surface runoff and ground water right to the septic tank inlet where the pipe was not sealed at all.
    
    Our contractor poured a concrete seal around the tank at this location - not a repair that will tolerate future settlement of the tank or pipe, but ... well, it worked this time. (The bottom of this septic tank was by coincidence on bedrock).
• If we see wastewater entering the septic tank at its outlet pipe connection or baffle: we need to figure out which of several unacceptable conditions exist, since this clue means that the drainfield is flooded, clogged, blocked, or basically at the end of its life, or that there is a groundwater leak into the system. In short we should not see water backflowing into the septic tank during pump-out nor at any other time.
  
  This condition is easier to detect if the septic tank outlet baffle cover is opened and watched during septic tank pumping and almost impossible to see otherwise, but an astute, experienced septic pumping contractor knows to listen during septic tank pumping.
  
  The step by step septic tank opening, pumping, and inspection procedure are documented
  
  at SEPTIC TANK PUMPING PROCEDURE.
  
  As the waste level in the tank falls the pumper listens for the sound of splashing - of water entering the tank. by watching and listening at both inlet and outlet ends of the tank s/he can observe this important clue. Possible causes of back-flow into the septic tank at its outlet include:
  • Failed septic effluent pump (or check valve) in a pump-up system intended to pump sewage effluent to a mound or raised bed septic system that is located uphill from the septic tank itself. If your septic system works entirely by gravity you won't have this component.
  • Broken, clogged, damaged piping between the septic tank and Distribution box or D-box. This condition is not most-common but might be traced to vehicles driving over the drainfield area, tree roots, or settlement of piping due to poor construction
  • Broken, tipped, clogged D-box that is not sending wastewater to the individual drainfield lines. Not very likely since usually at least one of the drain lines will still be taking effluent, or flooding occurs first at the D-box itself since in a gravity system it's downslope from the septic tank.
  • Groundwater leakage into the septic tank at its outlet end pipe connection. A poorly-sealed sewer line at the septic tank outlet may permit local surface runoff or groundwater to leak into the septic tank.
  • Drainfield / soak-bed failure: a sluggish drainfield will accept wastewater out of the septic tank but at a rate slower than wastewater enters the tank.
    
    Depending on the extent of drainfield soil blockage (or partial drainfield piping blockage) the septic tank wastewater level may rise to flooded condition only when the system is under heavy use: multiple visitors, multiple loads of laundry.
    
    Watch out: running toilets or a water softener stuck in back-wash or regeneration cycle mode will also flood a drainfield and may show up as a flooded septic tank.
• If we do not see water entering the septic tank at its inlet or outlet pipe connections, nor from the drainfield itself, there maybe other leaks into the septic tank. Check these locations:
  • Leaky septic tank cover: groundwater or surface runoff may enter at a septic tank cover itself (the cover of the entire septic tank)
  • Leaky septic tank cleanout or inspection covers: leaks at the septic tank top openings (there may be three, one at either end and one in the center used for cleaning) can flood a septic tank if there is surface or subsurface runoff in the area.
  • Leaky septic tank riser base: when a septic tank access riser is installed, the base of the riser needs to be sealed to the septic tank cover (typically using an epoxy putty) to prevent water entry at that point.
  • Septic tank bottom or side cracks or damage: the body of a septic tank may be cracked or have developed a hole due to vehicle traffic, tank settlement, tank age, or for steel septic tanks most commonly by rust.
    
    These openings may leak ground water into the septic tank in wet weather, flooding the septic tank, while in dry weather the inspector might find the septic tank wastewater level abnormally low as sewage effluent leaks out of the tank.
    
    Leaks in plastic, HDPE, fiberglass and concrete tanks can often be repaired. A rusted steel septic tank usually needs replacement.
  • More about septic tank leaks can be read
    
    at SEPTIC TANK LEAKS

Watch out: at FLOODED SEPTIC SYSTEMS, REPAIR [live link is given at Continue Reading just below] we explain how to fix a problem with septic tank or soakbed or drainfield flooding.

But be warned, that while in an emergency we might pump the septic tank, simply pumping the septic tank won't fix this problem and worse, if the back-flow rate into the septic tank is rapid (as it often is) you are simply wasting your money as back-flooding from a drainfield or surface runoff will quickly fill the septic tank again in hours to days.

Flooded Septic System Resources

• FLOODED SEPTIC SYSTEMS, REPAIR
• Michigan DEQ, SEPTIC SYSTEM FLOODING FAQs [PDF] Michigan Department of Environmental Quality Drinking Water and Municipal Assistance Division Onsite Wastewater Program retrieved 2019/08/27 original source: https://www.michigan.gov/documents/deq/deq-eh-onsite-Septic_Systems_and_Flooding_626114_7.pdf
• SEPTIC TANK PUMPING MISTAKES
• SEPTIC BACKUP PREVENTION for tips to avoid a septic problem during times of anticipated heavy septic system usage.

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Reader Q&A - also see RECOMMENDED ARTICLES & FAQs

My leach field floods in the yard and flows backwards into my septic tank

Hello, thanks for all the great information your site provides. I live in Southeaster VA, 60 feet above sea level. My house is 17 years old and I bought it 2 years ago. I have septic problems. I will try to make this short, but I will give you all the info too.

My leach field is flooding the surface of my yard. I have planned to replace the field, but I decided to talk to a professional about my problem before making a wrong decision.

Basically he said there is a "why" to the reason my field is failing. He asked do I have any leaking toilets or anything else, answer is no. I thought it may have been crushed by a heavy truck I had in the yard.

My own fault. I inspected the D box, all seems fine there. He said it sounds like you might be pumping extra water into field for some reason, and that's why I'm having problems. We have had the wettest winter in over 20 years. I have concrete 2 tank system. The 2nd tank to pump the effluent to back yard. Recently I had them pumped out the monitored the pump tank.

After a recent rainstorm of about 2 inches of rain, I checked the tank. The effluent level rose 2 feet overnight. So, there has to be a leak. Thus the extra pumping into my leach field and failure.

Ok, so is there a leak, but how and where. With the tanks relatively young, (I pour concrete for a living) I doubt they are broken. What about the gasket for tank tops or the pipe in between the 2 tanks. What would be the most likely ground water intrusion to the system?

No tree roots remotely close. - 4/17/14 Joe Paciga

Reply: tips for diagnosing septic tank back-flooding problems

I've dealt with this leach field flood problem as have countless others for a long time now and appreciate the frustrations involved. The professional you cite names some reasons that the field could be flooded, but may be shooting in the dark in that unless we do some diagnosis we don't know what's actually going on and don't know what to fix.

I agree that a running toilet or water softener stuck in regeneration cycle can flood a drainfield.

So can water leaking into the tank at the tank top, at the tank inlet, tank outlet, or from a crack or damaged tank bottom, sides, or cover or from an improperly sealed septic tank access riser.

Water can also back-flood a septic tank (I'm more or less "inventing" this term but it will be obvious to most) by running backwards from a flooded septic drainfield into the septic tank.

The drainfield may be flooded by high ground water (which means the drainfield is not properly constructed and is too low), or by mishandling of surface or subsurface seasonal runoff that needs to be intercepted and directed away from the drainfield using a curtain drain or surface swale or both.

10 year old Vernon County Wisconsin septic system failure diagnosis & repair steps - effluent on the ground surface - photos of what we found

Our septic system is about 10 years old and we have been told we already need a completely new system.

We noticed standing water on top of the ground.

The drawing is supposed to show what type system we have as I'm unsure, We have the ground dug up where we noticed the standing water and it is very soggy where you can see a pipe.

I can send additional photo's if I'm allowed to upload more than one. Please help, Thank You! - On 2021-10-04 by Don Prestwood -

Reply by inspectapedia.com.moderator (mod)

@Don Prestwood, @Anonymous,
It would be helpful to know more specifics about your situation.

Who told you you need a complete new system? How was that diagnosis made? What problems with the system were identified besides the area of standing water? What country, state, city are you located?

There are a number of reasons a septic system may fail that may include one or more parts of the system: septic tank, drainfield size, drainfield piping, etc. And the problem(s) may result from any number of sources. But some problems can be fixed without replacing the entire system.

Some additional information to review is found at:

SIGNS OF SEPTIC SYSTEM FAILURE

Because you don't want to fix more than is necessary or to spend more money than is necessary, let's try to get more information to help us better answer your questions.

Include any more photos you would like, one photo per comment but as many comments as you wish.

Follow-up by Don Prestwood

@inspectapedia.com.moderator, The person who installed the system about 10 years ago said we needed a complete new system. we could smell sewer but seems mainly outside. Wife says she could some in shower but I could not.

I have many pictures on my camera with the problem area dug up which I have yet to download onto my computer and upload here, will try to get that done today (Saturday). I did call a place that rejuvenates systems and he told me these people who say we need an entire new system is telling that to all the people who had our type of septic installed but it is untrue.

He even knew without telling him about how long ago we must of had it installed. He said he can do the rejuvenation at a sum of $1800. this coming Monday and guarantees his work.

On 2021-10-10 by Don Prestwood - photos of components of failed septic system

@inspectapedia.com.moderator, First of all I would like to say thank you for trying to help out, I REALLY appreciate it! In the first picture you will see the problem area where there is plastic in the ground *and floods with water) and we have noticed a piece of that plastic broken out of it.

At the top of that photo is where the 3 pipes come out of the ground. In the background of the photo of the 3 cement tanks you will see where we have dug up the ground. I hope this helps. Thanks again!

On 2021-10-09 by inspectapedia.com.moderator (mod) - basic checks on septic drainfield failure

@Don Prestwood,

Flooding in the drainfield often means the field is in total failure and needs repair; but that's not the whole story.

First we need an accurate diagnosis of your system.

1. Subsidence along the length of drainfield trenches

is normal as original backfill settles, and is not itself indicative of a failure; however if that or surrounding surface contouring fails to direct surface runoff away from the drainfield, that needs to be corrected.

Normally we don't add much fill atop a drainfield as burying it blocks needed oxygen and transpiration/evaporation. But it's ok to fill subsidence along the trench lines up to surrounding grade. (Wait on this).

2. At which end in your drawing does septic effluent enter the fields?

If at the upper dnd at your "tubes marking and if the puddle is at lower or final end of one of the trenches, then that trench end may be in failure but the reset of the field working.

3. Inspect at the 4-inch effluent pipes or "tubes":

if you see standing effluent there then the line where you see it is flooded and in failure. Use a sewer line camera described in our INDEX to RELATED ARTICLES.

If you don't then you might close off the single failed line and live with the two working lines until you're ready to face repair - it'd not be an emergency, but you've lOst 1/3 of the field capacity. (Conserve water to extend field life)

4. If the lines are not flooded

at the inspection end and if effluent enters at that end, send a sewer line cam down each line to inspect its condition. You could find a blockage or a break or collapse or uneven slope that would be diagnostic.

5. If you are seeing a drainfield line

(an actual pipe) at the surface at that "water hole" marked on your drawing, then the septic field is not properly built and not properly-installed and that'd suggest we want to know the depth and materials and trench dimensions and amount of gravel in all 3 of the trench lines. And I'd be more pessimistic about a system failure.

6. Excavate one or more sample locations of the failed septic drainfield trenches

so that you can see how the fields were constructed.

Look for proper trench dimensions, spacing, use of gravel, piping material, location of pipe in the gravel bed, signs of damage, etc.

Follow-up by Don Prestwood

The following photo's are when the septic guy came out the first time and dug it up. The pipe he cut off then capped the end does not even look like it was long enough to go into the plastic shroud.

When he came back and filled in what he dug up (then told us we need a complete new system), we dug the ground back up ourselves and noticed the end cap was taken off and a longer pipe was put inside the plastic thing that I think is a tank.

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On 2021-10-10 by Don Prestwood - failed septic installation in Vernon County Wisconsin

Vernon County, WI 54665. And here are more photo's of when our septic guy came. He is the one who installed the system 10 years ago and the one who told us all these systems that were installed, have failed.

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On 2021-10-11 by Don Prestwood - more photos of failed septic system during excavation

I hope you can see all the photo's and explanation I sent for I can't on my end. Thank you!

These are the last 2 photo's taken. One from the front angle and the other heading back to the 3 pipes that come out of the ground.

I have no idea what happened to this shroud looking thing but it was gone when we dug the ground back up.

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Reply by inspectapedia.com.moderator (mod) - Your photos include these signs of an improper septic drainfield installation that is not likely to work

@Don Prestwood,

I didn't see perforated pipe but I suspected that there are black flexible corrugated drain lines installed with no surrounding gravel.

I also see improper connections: solid PVC drain lines simply shoved into one end of larger diameter drainfield lines

Instead someone covered it with a geotextile.

It looks like an amateur attempt at a no rock or gravelless septic system and I'm not optimistic about its ability to function.

Watch out: There's no septic rejuvenation system that actually works successfully for any extended time.

And no septic "fix-up" treatment is going to have any useful effect whatsoever on an improperly constructed septic drainfield like one "installed" by laying pipes in heavy clay soil with nothing else to permit drainage, absorption into soil, bacterial treatment, etc.

To me this looks like a completely inadequate septic field installation, perhaps one installed without a soil perc test, permits, inspections, etc.

You need an on-site septic design engineer to do some soil perc tests and to inspect the system that's installed. I suspect she's going to tell you that you need a new, properly designed septic system, and depending on the site and soil conditions an in-ground system may not be suitable. I can't really tell that from just your photos.

On 2021-06-29 by jhaug76 - how do I diagnose septic field issues in our new home - can't flush toilets if the soil is wet

We recently started having septic/drain field issues. We have been on our property for 20 years and never had a problem. We have a new home there now with a new foundation.

When the ground is saturated due to rain or sprinklers we can't flush the toilets and the washing machine will back up into the tub.

The toilets gurgle as well. We had the tank pumped (second time in 5 months) and it lookes like there is another smaller tank between the house and main tank. There is no access to this but we saw sludge coming from it. The water from the drain field was also pouring into the tank. And suggestions on how to diagnose this properly as I don't want to just throw money at it?

On 2021-06-29 by inspectapedia.com.moderator (mod) - recently started having septic/drain field issues

@jhaug76,

1. Your septic system is either blocked or in total failure; wet weather saturation makes the failure show up but it's there regardless: a septic system as to work in all kinds of weather not just the dry season.

2. Pumping the septic tank prolongs field life but will never fix a failed drainfield nor remove a blockage there.

Scope the lines.

 

On 2020-09-05 by Nilda - Dirty water after power failure: septic problem?

A few weeks ago we had a power outage which caused my water line to stop dispensing water. When the power came back on I went to turn on the faucets and I heard a loud boom.

When the water came out it was dirty and it smelled really bad. Now my water is very rusty and if it sits for a day I come back to a rusty toile

On 2020-09-05 - by (mod) -

Nilda

That does not sound like a septic tank problem, the topic of the article on this page.

It does sound as if your well may have Ben struck by lightning or well pump wiring may have for some other cause short-circuited. It's also possible at the well casing was damaged. I would ask plumber or well driller who has an inspection camera to inspect the well bore as well as to check the condition of your pump and wiring for safety.

On 2020-05-01 by andrealb2010@gmail.com - septic tank water rises above the tank lid; we are using a septic tank treatment product - still in trouble

Hello. We have old, homemade septic system in house we've lived in for a bit over 5 years. Had tank pumped about 3 years ago. Noticed water overflow above tank lid but drain field is dry. We just had the tank pumped again, about 2 weeks ago.

Used Roebic K-57 to treat right after. No issue for about 2 weeks then tank is overfilling again, baffle is submerged.

Water rises above the lid, after bath lets out but slowly drains, but tank remains overfilled. Doesn't seem to rise above lid if just flushing toilet or doing dishes. Only letting out the bath.

We know that previous homeowner replaced the drain field at some point but tank is original and homemade. House was built late 60's early 70's. Thank you!

On 2020-05-02 - by (mod) -

Andrea,

That sounds like a faiked drainfield.

No treatment, nor pumping will fix that.

Some further investigation is needed.

 

On 2019-10-14 by Jane D - Septic system failed after the inspector ran water and flushed toilets

Hello. We had a septic inspection done to sell the house. The inspector ran the water and flushed and flushed the toilets for about an hour. We never had a problem before but after he left we did have a problem , the septic failel, the yard was full of water

Besides that my well is giving us problems

On 2019-10-14 - by (mod) -

Jane:

I'm sorry that you've had septic and well troubles after a home inspection. I have comments that point out two different situations:

1. If the inspector's test was within normal recommended limits

- such as a minimum water flow of 50 gallons per bedroom) then the inspection has disclosed upsetting but nonetheless genuine failures in the septic (and perhaps a well flow rate limitation) that are important for both seller and buyer to know now - before someone buys the house, finds these problems the day after they move in with 5 kids and 9 loads of laundry and give their lawyer a furious phone call about having been bamboozled by a home seller and their real estate agent.

2. If the inspector did something that was inappropriately aggressive

ke running more a thousand gallons of water into the septic system - then they nevertheless have probably disclosed a failing septic system but the results are more difficult to defend.

So you want a credible estimate of just how much water was run, not just how long it was run. (Running water for 1 hour at 2 gpm is insufficient: 120 gallons, while running water at 1 hour at 20 gpm: 1200 gallons - is more aggressive than normal because it probably exceeds the design parameters of the septic system.

In my experience, in every case - over 40 years of inspections and tests - whenever a septic test sent water to the surface, no matter how questionable the test itself - we discovered a failiure of the septic system; a look into the D-box or in the tank can usually tell us more information about the history of the system and its condition, such as seeing signs of baffle overflow or abnormally high levels in the tank or in the D-box; and we may see historic seepage evidence around the drainfield - or not.

I'm sorry to say that you'd be in an ugly position if you try to prove that your septic system is flawless and try to warrant that to the seller. So some further diagnosis of just what's wrong with the septic will be valuable. That along with some history: the age of the system, its design, size, soil conditions, maintenance history, tank and D-box condition all give a more-full idea of what's there and what repairs may be needed: ranging from fixing a clogged or broken line to budgeting for a field replacement or more.

About the well: if a well has a marginal recovery rate AND someone ran a lot of water they may have run the well dry or nearly dry. Usually in that case, let rest for a few hours to overnight the well will recover.

So how long has it been since you saw well trouble? That'll tell is if we need to be looking further for a problem (such as debris clogging, silt, sand, or an equipment issue to be fixed.)

On 2019-07-10 by Tonya - Waste flows out of pipe connecting septic tank and toilet

The pipe that is coming from the toilet to the septic tank has a hole like someone put it there. But when we flush the water from.the toilet is coming out of that hole not going the septic tank.

Reply by mod

Tonya: you're describing at least improper or damaged sewer piping and a health hazard. It's also possible that the septic system has failed, won't accept wastewater, so is backing up and flowing out of a broken sewer pipe.

You need an onsite septic contractor to diagnose and fix the trouble.

On 2019-04-11 by ella seneres - Septic failure after it rained cats and dogs - told not to pump the tank

Hi, I just had my septic tank pumped, and I failed to properly seal the lid, with a tarp then dirt. So I noticed a pool of water, and I saw more dollar signs in my future. But when I googled it, it said you must not pump out water from the tank as it will damage it.

I cannot ask my tenants to stop using water, as they are to used to wasting water with lots of laundry.

So I may be forced to pump it out if it will not damage the tank. I myself cut back severely no dish washing for a month, a rare shower twice a month, beginning to feel real ripe, and not much toilet flushing. And lastly if I do not pump it out how long on average would it take to drain into the leach fields, its 2500 gallons. Thank you.

Sorry forgot to mention; it rained cats and dogs, and that is how it filled up with California rain. Thanks again.

On 2019-04-11 - by (mod) - pumping the flooded septic tank won't fix it - we need a proper diagnosis

Ella

I think someone has given you confusing information. Pumping a conventional septic tank does not ruin it damage you can or harm it. However it doesn't need to be pumped over and over again. The pumping frequency is given in the septic tank pumping schedule article in this series and depends on the size of the tank and the Wastewater volume or number of bedrooms or number of building occupants.

However if surface water is leaking into your septic tank it will flood the tank and flood the drain fields and possibly ruin them. That's a question to have answered by your septic contractor.

Watch out: if a septic tank or cesspool is home-made out of stacked stone or concrete block, indeed it can collapse if it's pumped out. Such systems are unsafe; keep people away and have it inspected by an experienced septic system contractor.

On 2019-04-09 by erics - can a septic tank failure damage the drainfield? Tank is flooded.

We have a 2 tank septic system. About 2 months ago, our pump went out. The tank full alarm did not go off and we called somebody as soon as we saw standing water above the tank. They came out the next day, pumped the tank, replaced the broken pump w/ a more powerful pump, & fixed the alarm.

Ever since then, it seems like the system is struggling to keep up with our usage (which has not changed).

The pump is always running. I can hear & feel it when standing above the tank.

Maybe the old pump was always running too and I just couldn't hear the less powerful pump. The alarm warning light is almost always on too. We even had the audible alarm go off when we happened to be using a lot of water at once. This was never an issue before.

When I called the same guy that installed the pump, he said it sounded like an issue in the septic field.

It sounded like the next step in solving our problem, at least according to him, would be expensive. He said something about hydrostatic testing that could cost several thousand dollars depending on how many branches and how deep they are. Before agreeing, I wanted to do a little research (which is why I am here).

I've done some reading on this site and others and from what I can gather, it does sound likely that it is a drainfield issue.

It just seems odd that we did not have any problems before the new pump; however, after the new (more powerful) pump, our system suddenly has problems keeping up. It seems unlikely that our septic field would suddenly get clogged.

This especially seems true since it has two sides and it seems to me like any issue caused from the overflow would have only affected the one side, but we are now having problems regardless of side.

I'd like to think that I can trust the technician, but I am a bad judge of that sort of thing and I hate the idea of wrongly doubting an honest guy.

Questions:

1. Could the initial tank overflow issue cause issues in the septic field? In case it matters, the tank had been emptied a year prior.

2. Could anything the technician have done when replacing the pump cause this kind of issue?

3. What is the proper next step to diagnose the root issue and how much should I expect to pay?

4. I'm reasonably handy and not afraid to get dirty. Is there anything I can do to diagnose/fix/etc?

5. If I need to call somebody, should I call the same guy or have a new guy that could also verify his previous work?

6. What should I be asking but I'm not?

On 2019-04-10 - by (mod) - yes

Eric

I think you're on a reasonable diagnostic track by looking into the drainfield condition.

"The [septic effluent] pump is always running" tells me that your drainfield or tank or both are flooded. The root cause can be a failed drainfield, preventing actual disposal/dispersal of septic effluent.

Also, Yes a septic tank failure can damage a drainfield, in particular if a baffle is broken or overflowed such that solids are pushed out into the drainfield piping and leach lines.

Take a look in the D-box to see if there is flooding there.

Then you may need to have someone with a sewer camera check your leach lines for obvious damage, flooding, or sewage solids - as a step that might be worth doing before exploratory digging.

...

Continue reading  at FLOODED SEPTIC SYSTEMS, REPAIR to read suggestions for repairing a flooding septic tank or soakbed system, or select a topic from the closely-related articles below, or see the complete ARTICLE INDEX.

Or see SEPTIC TANK BACK FLOODING FAQs - questions about flooded or abnormally high levels in the septic tank due to drainfield back-flow, posted originally at this page

Or see these

Septic System Flooding Diagnosis & Repair Articles

• FLOODED SEPTIC SYSTEMS, REPAIR
• PUMPER TRUCK OPERATION PROCEDURE where we explain how to spot backflooding during septic tank pumping
• PUMPING the SEPTIC TANK to continue with the septic tank cleaning & inspection procedure
• SEPTIC D-BOX FLOODING
• SEPTIC BACKUP PREVENTION for tips to avoid a septic problem during times of anticipated heavy septic system usage.
• SEPTIC DESIGN for FLOOD DAMAGE RESISTANCE
• SEPTIC DRAINFIELD FAILURE DIAGNOSIS
• SEPTIC SYSTEM BACK-PUMPING
• SEPTIC TANK BACK FLOODING
• SEPTIC TANK PUMPING MISTAKES
• SEPTIC SYSTEM BACK-PUMPING - pumping out the drainfield is not useful

Suggested citation for this web page

SEPTIC TANK BACK FLOODING at InspectApedia.com - online encyclopedia of building & environmental inspection, testing, diagnosis, repair, & problem prevention advice.

Or see this

INDEX to RELATED ARTICLES: ARTICLE INDEX to SEPTIC SYSTEMS

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