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Septi tank cleanout started (C) Daniel FriedmanSeptic Tank Cleaning
Pumping Mistakes to Avoid

Septic tank pumpout SNAFUS:

This article describes common mistakes and misunderstandings about cleaning or pumping the septic tank. We explain why pumping too infrequently (or never) is a bad idea but we add that pumping more often than necessary is more or less tossing money down the toilet.

We also explain why a septic tank is normally always "full" and that after pumping the septic fills up pretty quickly in normal use. The article also describes effective vs. ineffective septic tank pumping and how you can improve the septic tank cleaning procedure so that pumping the tank is actually useful.

Finally we note immediate & serious safety hazards that should be addressed when cleaning septic systems.

InspectAPedia tolerates no conflicts of interest. We have no relationship with advertisers, products, or services discussed at this website.

Avoiding these Septic Pumping Mistakes

Septic tank inteiror viewed during cleaning (C) Daniel FriedmanFour septic tank pumping schedule mistakes

  1. Failure to pump the septic tank frequently enough: leading to an early drainfield failure and to the need for costly repairs
  2. Pumping or cleaning the septic tank too frequently, wasting money (though you're wasting a lot less money than the cost of a new drainfield.

    [Click to enlarge any image]

    Some septic pumping contractors and some other "experts" give a fixed rule of thumb that gives advice that is safe and profitable such as "pump your septic tank every year" or "pump your septic tank every two years". This advice is safe but except for unusual circumstances it is wrong.

    Contractors may give this advice without first having actually considered any information about the actual septic system capacity, size, level of usage, age, or other conditions.

    The OPM Problem: It's a great example of "OPM" or "other people's money" - spending someone else's money to reduce your risk that they'll complain that your advice wasn't safe enough.

    In a failing septic system case in Minnesota, the contractor assured that "things will be fine if you just pump the septic tank every couple of months or after you've had a lot of visitors". The theory is that you pump the septic tank the septic tank after heavy usage to "get back to normal".

    It might be smarter to pump the septic tank before or both before and after heavy use when we know a septic system is marginal. But this can be pretty expensive.

    Using a hired port-a-john might be much less expensive and might help avoid a sewage backup.

    See SEPTIC BACKUP PREVENTION for tips to avoid a septic problem during times of anticipated heavy septic system usage.

  3. Pumping the septic tank to "fix" a clogged or failing drainfield. All you really gain is a few days of toilet flushing before the tank has re-filled, or at most weeks of respite.

    More frequent pumping of the septic tank amounts to treating the septic system (tank and disposal fields) as a septic holding tank system instead - a costly proposition that may be necessary in some emergencies but not an attractive solution to onsite wastewater disposal.

    More about this snafu is provided below.
  4. Pumping the septic tank before a septic system inspection or test.the purpose of this tank pump-out is to hopefully prevent the inspector from finding evidence of a failed drainfield. An empty septic tank prevents the test-inspector from pushing any effluent into the drainfield.

    See WHEN NOT TO PUMP A SEPTIC TANK.

Ten Septic Tank Fantasies - costly misconceptions worth reconsidering

Septic tank schematic showing scum and sludge layers (C) Carson Dunlop AssociatesIf you're normal you don't have fantasies about septic tanks. OK let's call these "septic tank misconceptions" that are worth clearing-up both to save money and to care for the system effectively.

[Click to enlarge any image]

Septic tank fantasy No. 1: we need to pump out the septic tank whenever the septic tank gets full

Wrong.

A septic tank in normal use is always full, right up to the bottom of the outlet pipe (near the top of the tank). After pumping it out completely, an empty septic tank fills up again under normal usage in just a few days, after which it is again discharging liquid effluent to the absorption field, soakaway bed or leach field - names vary by country.

In a normally-working conventional septic tank we find wastewater, or "blackwater": a combination of watery sewage effluent, a floating scum layer at the tank top (in Australia the "scum blanket", and settled sludge in the bottom of the tank.

If as in the sketch above we could see a cross section of the septic tank contents (if we wanted to) we would know when pumping the septic tank is actually necessary based on its sludge and scum layers - that is, based on data instead of either theory or wild arm-waving.

A septic pump-out is needed when the thickness of the floating scum layer and settled sludge layer occupy so much of the tank volume that the free liquid area is "too small" - the "net free area" has become so small that
t
he EFFLUENT RETENTION TIME,

the time that wastewater has in the tank to allow for solids and floating scum to separate from effluent being discharged to the drainfield (soakaway in the U.K.) is too short. This gives new meaning to time is short, right?

Short septic tank effluent retention time means we're pushing solids into the drainfield, clogging it up & shortening its remaining life.

Two valid septic tank cleaning approaches involve either using

the SEPTIC TANK PUMPING SCHEDULE or using objective data obtained by actually inspecting the septic system, diagnosing any problems or failures, and inspecting conditions inside the septic tank.

In part II of this discussion

SEPTIC TANK OBJECTIVE DATA we explain how a septic contractor can measure the scum and sludge layers.

That's a step that's sometimes worth the trouble and that might be taken the next time you have the septic tank pumped.

You can't see into the septic tank, but a contractor, by opening the tank

can MEASURE SEPTIC TANK SCUM & SLUDGE.

Pump the septic tank when ANY of the following is TRUE

If you're are among the two percenters who want to become expert on this see or

see SEPTIC TANK LEVELS of SEWAGE.

Finally, sometimes extra septic tank pump-outs are useful - something that we will discuss below.

Septic tank fantasy No 2: additives and chemicals will fix or extend the life of the septic system

Nope.

In a conventional and most other septic system designs not only do additives, chemicals and treatments do little or no good, some can damage the system, causing frothing, causing solids to be discharged to the drainfield.

No expert recommends the use of septic treatments or additives, and these substances are illegal to use in many jurisdictions in the U.S. and Canada, at least in part because some of them are also toxic and are environmental contaminants.

Details are at CHEMICALS & TREATMENTS for SEPTICS.

Septic tank fantasy No 3: some septic systems never need to be cleaned, pumped, serviced.

Septic tank failure lawsuit - total tank impaction an collapse (C) Daniel Friedman

Nope. As my Mom used to day, in your dreams, buster.

The septic tank shown at left was totally packed with solids and was collapsing - it had not been pumped in decades. The home, occupied by a single elderly person, limped along until new owners bought the property and tried taking a couple of showers.

The morning after the new family moved in sewage was coming up in the yard. This case is discussed

at SEPTIC FAILURE LAWSUIT.

It is true that the required septic cleanout frequency varies not only by tank size, wastewater volume being produced, and system design, and some systems require less frequent cleaning for the same usage level compared to other designs, but all septic systems need periodic maintenance.

Failure to properly maintain the septic system is the No. 1 cause of early septic system failures.

Septic tank fantasy No. 4: pumping out the septic tank can restore or save a failed or failing drainfield

Unfortunately, a drainfield or soakaway bed that is in failure would require an estimated 5-10 years of total rest to "recover" enough to be restored to normal use.

Even then the field won't work if it's flooded or if the field has been damaged by vehicle traffic, tree roots or similar troubles.

What you actually get by extra septic tank pump outs in an area of failed drainfield is a few days (less than a month) of toilet flushing and wastewater disposal into the septic tank until it fills up again and is again trying desperately to push septic wastewater effluent out into the soakaway bed.

How quickly does the septic tank fill up again? Experts estimate as much as 200 gallons of wastewater is generated per occupant per day

Even using a fantastically small number of 50 gallons per person per day in a home where extreme water conservation measures are in effect or where there is a single elderly occupant using very little water, the septic tank still fills up quickly - typically in as few as 1-2 days, or at most in about 20 days of use.

Resting a failing or failed drainfield for 20 days doesn't fix anything.

Septic tank fantasy No. 5: all we need to do is pump the liquid out of the septic tank

Septic system failure days after tank pumpout (C) Daniel Friedman

Wow what a mistake this is.

At left I show sewage effluent running down a hill over rock.

That straw-covered pile in the top of the photo was covering the septic tank that the property seller had asked her septic contractor to pump out just a few days before my inspection.

That the system was in total failure was evident after just two days of household use of the septic system.

The tank had re-filled in that time, then sent effluent to the property surface.

To be of any use at all, when pumping the septic tank we need to remove the settled sludge and floating scum from the septic tank, not just the liquid effluent.

If the septic contractor just pokes that septic tank pumping hose down into the middle of the tank and just pumps like mad all she's doing is removing the effluent.

The sludge stays on the tank bottom - or most of it does - and the floating scum falls down to rest nicely atop the sludge layer.

Septic tank cleaning showing use of the hoe or rake to get up the sludge (C) Daniel FriedmanWhat is our septic tank pumping contractor doing with that pole in his right hand while he manipulates the pumper truck hose with his left?

He's using long-handle hoe-like tool to scrape and stir up the dense sludge on the septic tank bottom, mixing in a bit of liquid so that the vacuum hose can pull the sludge out of the septic tank.

Your guy doesn't do this? Interesting.

Watch out: If your septic tank pumping company tells you it's a good idea to leave solids in the septic tank - we know of a company that actually returns solids to the septic tank after separating out the effluent in their special pumper truck

- Just Say NO! Tell 'em not to let the door hit their backside while they're on the way out.

You need to find a different septic pumping service.

The We Pump it & then We Put it Back septic pumping company is simply saving themselves the cost of disposing of sewage from their truck, they're not doing anything to help your septic tank nor system and they're speeding the demise of the absorption field.

The object of tank pumping is to remove the solids (sludge and scum) from the septic tank and thus to increase

EFFLUENT RETENTION TIME.

An effective septic tank cleanout removes the scum and sludge by moving the pumping hose around and by using the liquid effluent to help break up and pump out the solids.

If the pumper just tackles the easy task of pumping out the liquid effluent itself he's not performing a useful job.

Just pumping out liquid effluent doesn't benefit the system. In fact, just pumping out effluent and leaving the solids means that after every such unfortunate "mis-service" of the tank the actual remaining tank volume available for wastewater treatment is less and less.

Septic tank fantasy No. 6: it's possible to pump the septic tank through a small-diameter pipe or riser

Using a small-diameter septic tank riser to empty a chemical toilet works but using to clean the tank ? (C) Daniel FriedmanNot easily, but it might be possible. In traditional septic tank cleaning operations the operator needs room to manipulate the septic pumper truck hose to remove the floating scum layer and settled sludge layer.

Without manipulation space and room to stir sludge and scum with a hoe, rake or other tool, removal of solids is difficult and might be limited.

At left we show small-diameter septic tank riser that has been used for years to "pump out" the septic tank at this Minnesota home.

I'm using this mini-septic-tank-riser to empty a small chemical toilet - which is OK as long as we respect the guidelines

at RV HOLDING TANK DUMP INTO SEPTIC TANK?.

But how thoroughly do you think the septic tank pumper can clean the septic tank working through just this small-diameter opening to reach a tank located several feet below?

Using a Manual Tool to Break Up Septic Tank Sludge & Scum for Pumping

Unless we do something extra (see below) it is just about impossible to remove most of these key constituents if all we can do is poke a pumper hose straight down into the septic tank.

Jimmy Herring (Herring Sanitation, Poughkeepsie, NY) demonstrated the right way to clean out a septic tank in the photos below. You'll see that Mr. Herring is working through a much larger opening - the septic tank access cover gives enough room to manipulate the pumping hose.

Septi tank cleanout started (C) Daniel Friedman Septic tank cleaning (C) Daniel Friedman

Crust-Busters to the Rescue!

Crust Busters provides a motor-driven auger that stirs up the septic tank floating scum and settled scum layers, permitting the septic tank pumper to successfully remove these constituents along with septic effluent.

The Crust Buster is a 33-pound motor driven mixing device that combines an 80-inch shaft with folding, hinged mixing blades that open out when spinning to break up and make septic tank solids pump-able through a small access port.

Depending on the diameter of the septic tank pumping opening the operator selects a 2-blade attachment that can slip through a 4-inch diameter opening, or a 3-blade attachment that is not collapsible and fits through a 12" or larger diameter opening. Crust Buster shaft extensions permit operating the device in deeper septic tanks. - Thanks to septic cleaning contractor Daniel Zeimet, Two Harbors MN, for this tip.

You could also fabricate your own septic tank sludge/scum break-up tool or scum and sludge measuring tool.

See TOOLS for MEASURING SCUM & SLUDGE.

Still Septic Tank Inspection Limitations May Remain

Still, working through a tall, narrow 6" diameter vertical riser, it is difficult if not impossible to inspect the septic tank condition and that of its baffles through such a narrow vertical access opening, even using a traditional flashlight and mirror.

See INSPECT the SEPTIC TANK DURING PUMPING

If we can't gain visual access to the septic tank interior or visual access by removing covers at the inlet and outlet ports, we won't know the condition of the tank, it baffles, its sludge and scum layers.

We also may not know if there are leaks into the septic tank or leaks out of it through damage or poor seals at any of its openings.

Septic tank cleaning opening (C) Daniel Friedman Septic tank inteiror viewed during cleaning (C) Daniel Friedman

Without using a larger septic tank access opening we probably won't know if a flooded drainfield is back-flowing into the tank during pumping, and we won't know how much sludge and scum were left in the tank. The photos above show important conditions that you cannot see through an 8" diameter septic tank riser.

Technical note: it's possible to add a large-diameter septic tank riser capped by a vehicle and child-safe cover to make future septic tank servicing more effective. But don't spend on this improvement before knowing that the septic tank itself will continue in use.

For example, a rusted-out steel septic tank is going to need complete replacement.

It may also be possible to gain improved visual access to an otherwise difficult-to-access septic tank interior using electronic gear including flexible borescopes, lights, and similar remote inspection camera-equipment: all added sophistication, complexity, and costs that may mean these tools are not in the hands of most septic tank pumping companies.

Septic tank fantasy No. 7: it's ok to discharge excess septic effluent from the septic tank to the surface, to a nearby drainage ditch, lake, stream, or to your neighbor's yard.

Septic dye test failuire shows up at the basement entry door - septic tank and fields under the ;arking lot? © D Friedman at InspectApedia.com

Are you kidding me?

In a conventional septic system (tank and soil absorption bed or drainfield) no more than 40% of the wastewater treatment is handled by bacteria in the septic tank. The rest of the wastewater treatment occurs thanks to bacteria in the soil.

Discharging such wastewater anywhere out of the treatment system is unsanitary, contaminates the environment, makes your neighbor mad, and is illegal virtually everywhere.

You are not even allowed to discharge graywater (washers and sinks) to the surface.

An exception is clarified highly-treated wastewater effluent produced by a properly working aerobic septic system and highly-treated wastewater from advanced septic system designs that treat effluent to a level equal to or exceeding the sanitary nature of ordinary ground water or surface water.

In these instances discharge of wastewater may be allowed by permit though for some installations a final wastewater disinfection step may still be required.

In some jurisdictions such as areas of the U.K., sewage treatment plants are required and traditional septic tanks and soakaways are no longer permitted. - Crystal Tanks, U.K. (2014)

Septic tank fantasy No. 8: if the toilets flush and drains drain the septic tank is working

Lakeshore algae less than 50 ft. from an old septic system indicates high nitrates and probable treatment failure (C) Daniel FriedmanNot necessarily.

Our photo shows heavy algae growth along the shore of a waterway abutting an older home whose septic system was installed in the 1970's.

No sewage effluent appears at the surface of the property, toilets flush (though slowly and badly) and drains drain (though sometimes slowly). There are no sewage odors at the property.

Even a septic loading and dye test may fail to show a system failure at this home.

Because the algae grows only close to this property we suspect that high nitrate discharge from a failed septic system is producing heavy algal growth in this spot.

The combination of age, algae, and slow burbling drains is an indicator of the condition of the system though there is no evidence of sewage effluent at the ground surface.

This septic system is in technical failure in that it is not properly treating the wastewater it receives.

Watch out: A system in this condition is also at high risk of sewage backup into the building.

Pumping the septic tank won't alleviate this trouble: days after the tank is pumped effluent will again be discharged into soils that ultimately drain into this waterway. Improvement in the treatment level within the septic tank might help (a conversion to aerobic?) or drainfield reconstruction may be needed.

Details are at DISPOSAL vs TREATMENT

and
at CLOGGED DRAIN DIAGNOSIS & REPAIR.

Pumping the septic tank may give temporary toilet flush improvements but it's not going to repair a clogged drain nor a failing drainfield.

Technical note: if an older grandfathered septic drainfield is closer to a body of water than current codes allow, its replacement may need to be relocated to a more distant location. In that event we usually can leave the septic tank in place, adding an effluent pump to move the tank output to the new absorption bed.

Septic tank fantasy No. 9: ok so we know the septic system is old and at end of life. It's ok to keep using it, right?

Well this fantasy has merit: sort-of.

We never want to call a contractor in a panic asking for an emergency repair: the price of the job doubles or worse, not only out of gouging or greed but because the contractor has to shuffle work, put off other customers, and maybe ultimately even lose that deferred business.

But considering the cost of having to clean up a major sewage spill in a building it makes sense to fix septic problems before the last possible occasion: when the system has suffered a catastrophic failure. Meanwhile here are some limp-along steps that can help defer the inevitable:

Septic tank fantasy No. 10: nobody ever actually fell into a septic tank

No, that's not true.

People really do fall into septic tanks, cesspools, drywells, usually with fatal results. The requirement to assure safe covers on septic tanks and similar equipment are important.

See this list of septic tank fatalities and other accidents SEPTIC TANK ACCIDENT REPORTS.

 




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Reader Comments, Questions & Answers About The Article Above

Below you will find questions and answers previously posted on this page at its page bottom reader comment box.

Reader Q&A - also see RECOMMENDED ARTICLES & FAQs

On 2022-06-08 by InspectApedia-911 (mod) - ensure that all contract terms were completed and documentation has been received

@Tara,

Before bailing out be sure that everything that you paid-for has been completed and provided to you: field survey, soil tests, explorations, written reports, design work, permits.

Keep us posted. How your case progresses will doubtless help others.

On 2022-06-08 by Tara

@InspectApedia-911,
Yes, the money was to identify the problem and get the survey/permit. No work has been done. Because it is a huge project, I went with a company that has been in business for 50 years and has good reviews. I called the engineers and asked if I can switch companies but keep them, just yesterday.

On 2022-06-08 by InspectApedia-911 (mod)

@Tara,

Good grief! You paid thousands of dollars simply for a survey and "plan" ?

Does that mean you and your experts already knew that the whole septic system needs to be replaced: tank and drainfield?

If so, and if you've got nothing for your thousands of dollars, you should contact the company and make clear that they have to either do the work or refund your money.

Pumping the septic tank will not fix a failed drainfield.

On 2022-06-08 by Tara

@InspectApedia-911, No, sorry I wasn't clear. They did one pump out for $500. Then I paid a few thousand for them to get the survey, permits, and an engineered plan.

It has been 15 months; so I feel like I need another pump-out. I also want it done. Also, each of my contacts is no longer there.

Lastly, the engineer told me that the plans were very difficult because we are graded down toward a creek, and have a well, a pool, and neighbors with septic 50 feet from the property line where they'd like to move ours. (NJ) So all that was done was a pump-out, two inspections, and a survey.

On 2022-06-07 by InspectApedia-911 (mod) - read your contract before paying any money

@Tara,

Hang on, here a moment. Is this right: you paid $500. to a company a year ago and they never did a thing, no inspection, no cleaning, no service, nothing?

Do you have a copy of your contract? If so take a look at it. What was the company obligated to do.

if the terms of the contract were not met

1. Do not pay another cent to the company, and consider asking for a complete refund as they did nothing

2. Find a different septic cleanout company and have them inspect and clean your septic tank.

You don't normally need your own permit or survey simply to have an existing septic tank cleaned and inspected.

But

Watch out: you may have been sold some sort of "insurance policy" for your septic - in which case you collected nothing and probably, in my OPINION, could have spent that money more wisely.

On 2022-06-07 by Tara

I hired a company to check out my old system 15 MONTHS AGO. Nothing has been done. In fact, they want me to pay FULL PRICE ($500) for another clean-out, since I'm worried about it backing into my home. After getting permits and surveys, is it possible to switch companies?

On 2022-04-27 by Inspectapedia Com Moderator (mod) - Is there benefit to removing sludge, then returning just the water to the tank?

@Barb Langer,

Thanks for a helpful question.

In my experience and OPINION, UNLESS the "water" being returned to the septic tank is very highly-filtered so as to be practically clear, the only benefit of doing so is helping the septic pumping company earn a profit and stay in business.

The danger is the following:

The action of pumping solids and liquid effluent out of the septic tank agitates the waste and also macerates solids to a degree as they pass through the septic pump.

As a result the level of fine floating waste inside the pumper truck's tank will be very high - much higher than it was in the septic tank itself before pumping (usually).

If then that fine-particulate wastewater is returned to the septic tank it will readily flow right out of the tank and into the septic drainfield or soakaway beds.

There those particles quickly clog the surrounding soil.

The result can be a significant reduction in the life of the septic drainfield and thus a significant expense to the homeowner when the drainfield needs to be replaced sooner than otherwise would have been necessary.

So as my mentor-friend Tampa home inspector Mark Cramer says: ... it depends.

It depends on how thoroughly the ground, pumped, agitated septic waste in the pumper truck is filtered before it is returned to the septic tank.

Is there ANY filtering at all? If so of what sized particles?

On 2022-04-26 by Barb Langer

Is there benefit to removing sludge, then returning just the water to the tank? Our septic cleaning company charges less if we will have the water returned to the tank.

On 2022-03-15 by Inspectapedia Com Moderator

@serenna peterson,

Yes, you are absolutely right. But make that requirement clear before the contractor starts work, not after.

On 2022-03-15 by serenna peterson

I am having my tank pumped today. My husband said last time it was pumped, the septic guy said they do NOT pump out the scum on the top of the tank. I told my husband they have to, that is part of their job. So I googled it. And it says they are supposed to pump that out.

I am going to watch this new guy pump the septic today, and if they refuse to pump out the scum, I will refuse to pay. Am I correct in this??

On 2021-11-28 by Inspectapedia Com Moderator

@Levi Armstrong,

It's worth taking the time, even when trying to sneak in ads for your septic company, to read carefully, Levi.
This specific article is on septic tank cleaning mistakes, not on septic design.

No single septic maintenance article can give clear coverage of every septic system design and maintenance topic.

In the Article Index you'll find thorough and unbiased guidance on septic system design, sizing, soil testing, wastewater flow estimates, as well as septic design codes and standards, etc.

On 2021-11-28 by Levi Armstrong

It's great that you mentioned that contractors might give this advice without considering any information about the actual septic system capacity, size, level of usage, age, or other conditions.

My brother needs help installing a new water well near his farm. I'll share this with him since he needs to know how to connect it to the tank. Thanks!

(Reposted by mod without dis-allowed link.)

On 2021-11-28 by Inspectapedia Com Moderator - useful approaches to septic tank pumping scheduling

@vivian black,

What you recommended in your ad posting is not correct.

There are two most useful approaches to septic tank pumping scheduling that save homeowners money while protecting the septic system.

1. follow the septic tank pumping schedule based on building occupancy or wastewater flow given at SEPTIC TANK PUMPING SCHEDULE

which does not agree your arbitrary "every year or two" advice for all septic systems.

2. base septic pumping on actual empirical data: measuring accumulated sludge and scum layers

On 2021-10-18 by vivian black

Thank-you for the information about pumping the septic tank just the right amount. It's good to know that if you don't pump it enough, it will lead to an early drain field failure which leads to expensive repairs. Also, pumping too frequently wastes money. It is good to know that safe advice is to pump once a year or two.

[Re-posted without dis-allowed advertising link - Mod.]

On 2021-10-18 by inspectapedia.com.moderator

@Jim,

Take a look at PUMPER TRUCK OPERATION PROCEDURE

where we also list some septic pumper truck suppliers.

Watch out: pumping out septic tanks is indeed a critical and valuable service, but don 't try it, not even once, before you have proper safety and functional training. Making a mistake can kill your customers, or you could be killed yourself. The most-common hazards include being overcome by septic tank fumes, falling into a septic tank, or causing a septic tank or drywell or cesspool to collapse. We've been involved in investigating, reporting, describing fatalities involving all of those.

Stay safe.

On 2021-10-17 by Jim

Looking to buy a truck that goes around to homes, businesses that empties out the septic tank. If anyone has info please call or text me 5709053678

On 2021-07-15 by Eve Mitchell

COMMENT: I love your tip about moving anything valuable off the lowest floor of your home. I had never thought about this in regards to septic maintenance, but it makes sense.

My septic tank is in dire need of pumping and I'm hoping to call a professional before it gets to a dangerous level.

On 2021-06-03 by mak.church (mod)

@Double compartment Septic Tank,

Please see see SEPTIC TANK PUMPING PROCEDURE step by step photo guideline of how to pump and clean a septic tank - septic tank care

Watch out: the first compartment in your septic tank is where solid sludge and floating scum are separated from incoming sewage or wastewater. That compartment is the most-important one to be pumped regularly, NOT the "second" compartment in your description.

It is possible to remove some of the liquid waste but it is not possible to properly clean and remove the settled solids nor floating scum by simply "reaching over a wall between the two compartments".

By failing to keep the first septic tank compartment cleaned, the accumulated sludge and scum layers ultimately reduce the net free area so much that small floating solids will be sent through your second compartment and out into your septic drainfield, clogging it and thus shortening its life and leading to need for expensive drainfield replacement sooner than otherwise.

On 2021-06-01 by Double compartment Septic Tank

I have a double compartment septic tank. I have it pumped regularly but I have always opened up the second compartment for pumping. I suppose there is a lid on the first compartment, but I have never dug it up and had it pumped. When they pump the second compartment is that good enough or should I be opening up both compartment lids?

The guy who pumps it has never said anything about opening up the first compartment. There is a wall between the two but it is open at the top. I was thinking he would just put the hose over the wall and do both compartments from the one hole. What do you think?

On 2021-05-25 - by (mod) -

@Devon,

Sewage sludge that may be at sufficient depth as to merit removal from a pumping chamber is not something a homeowner should handle - it needs to be removed by a septic pumping company who then dispose of it at an approved site. Combine septic tank (the main tank) pumping and cleaning with a cleanout of the pumping chamber.

Once you've done that you should find that cleaning the pumping chamber is needed much less often than pumping the septic tank itself - perhaps cleaning the pumping chamber every fourth septic tank cleanout.

On 2021-05-25 by Devon

sorry it's early. It is a septic pump chamber that pumps out our water 250' to a leach field. It is 10x10x7 roughly. I have been in there several times changing out the pump when it goes. It is the bottom of this chamber I would like to clean without having to actually get in there. Thank you though for your concern about the septic tank. We do have ours pumped out. After reading your article I realized..#1 we are having it pumped out way too often...#2 the company we use never cleaned the bottom. Thanks Dan

On 2021-05-25 - by (mod) -

@Devon,

Are we discussing a septic tank pumping chamber or a sewage grinder ejector pump. The latter is a small basin set into the floor of a basement or crawl space. That might be something a homeowner could clean using a combination of building and a disinfectant. But you should not attempt to clean your own septic tank. It's dangerous.

On 2021-05-25 by Devon

Hi, we need to clean the sludge out of our pump chamber before an install of a new pump. What is the best way to do this ourselves? Would a wet/dry vac work?

On 2021-04-10 by (mod) - Is a 3" clean out acceptable for pumping out a septic tank ?

@Mark McClure,

no, not to me.

The most that one could expect with just a 3-inch cleanout is that some of the liquid effluent and a small bit of the floating scum and solids are pumped out.

The technician needs a much larger opening in order to

- use a tool to break up solid scum and sludge layers so that they can be pumped out

- move the pumping hose about in the tank to pick up sludge from various areas

- check the condition of the septic tank inlet and outlet baffles

Since the purpose of the pumping operation is to remove solid scum and sludge, and as it's not possible to do more than a trivial job of that through a tiny opening, I wouldn't want to live with just a 3-inch septic tank cleanout point. It makes the cost of the pumpout a mostly-wasted expense and it fails to do what's needed to protect the life of the drainfield.

On 2021-04-10 by Mark McClure

Is a 3" clean out acceptable for pumping out a septic tank ?

On 2021-03-16 - by (mod) -

@Cliff,

In my opinion what you describe is a common septic pumping scam - one that risks serious damage to a drainfield as we pump agitated effluent containing a high level of small floating solids back into the septic tank and thus out into the drainfield where the field becomes clogged sooner than otherwise.

That's in part because the return liquid isn 't being adequately filtered.

**IF** you could find a septic pumper truck that could actually filter the effluent sufficiently to make it safe to discharge into the drainfield, then what you want might be technically feasible. That's not going to be a standard septic pumper truck.

On 2021-03-16 by Cliff

We live in a remote location where pumping costs are up $3000 per visit (large capacity system). Due to this we are trying to keep the visit to one truck and to maximize pump truck volume. We have been wondering if pumping out liquid into a separate vessel, having the sludge removed then pumping the liquid back in is an effective way of managing this. Essentially just removing sludge instead of lots of liquid too. Thoughts? Any insight appreciated.

On 2021-02-16 1 by (mod) - do NOT "re-fill" a septic tank after it has been pumped-out: it will re-fill on its own as you use water

Don

You should give an extra $50. in THANKS to your septic pumping company for being impeccably honest and working with your own interest in mind.

What your septic pumper told you: (it's not necessary to "re-fill" a septic tank after pumping) is absolutely correct. Dead right. Spot-on.

In normal use, wastewater from your home will re-fill the septic tank in a few days - depending on the size of the tank and the amount of water you use in your home.

There's plenty of bacteria remaining in the septic tank after pumpout and cleaning and plenty more bacteria entering the tank in your wastewater, so that's never a concern.

No septic tank refills are needed nor are any septic treatments or additives needed for a conventional septic tank and drainfield system.

In fact your question is the opposite of a very troubling practice that has been reported by some other readers who described a less-honest septic pumping "service" that pumped out their septic tank and then pumped stirred-up effluent right back into the tank before leaving the job. That practice is charging for doing almost nothing useful at all, and worse, risks destroying the drainfield by returning ground, agitated septic solids into the tank in a form that flows out into and clogs the drainfield.

I commend your septic pumping company.

On 2021-02-16 by Don Jlou

I had my septic pumped out and was told I did not need to refill with water. Is that correct?

On 2021-02-05 - by (mod) -

William

See details at SEPTIC TANK BACK FLOODING

and at

FLOODED SEPTIC SYSTEMS, REPAIR

and there is a diagnostic check that may be helpful, described
at
SEPTIC D-BOX FLOODING

On 2021-02-05 by (mod) - septic tank was filled up again a day after pumping

Good question, William;

If the septic tank is pretty small and your daily water usage in the home is high it's possible to re-fill a septic tank in a day or two, but usually it takes several days for the tank to re-fill.

I would check for a couple of things:

- at septic tank pump-out time after the tank is pumped, or even during the pump-out, watch the septic tank outlet end pipe and baffle to see if the drainfield is back-flowing into the septic tank; if it is the field is flooded and in failure.

- in the house look for running toilets or other improper water usage sources

- at the tank again, double check (by inspection) that surface runoff and groundwater are not leaking into the septic tank

Let me know what you find.

On 2021-02-05 by William

I pumped out my septic tank and a day later it's full of clear water I pump it out again it fills up again with clear water is this normal

On 2020-12-18 - by (mod) -

Dana:

The first compartment in a 2 compartment septic tank holds most of the scum and sludge; some accumulates, more-slowly, in a second compartment or settling chamber.

Both need to be cleaned, though the second or third etc. compartment usually need less-frequent pumping.

On 2020-12-18 by Dana

A septic company is touting that they pump both compartments versus their competitors. I have not found a discussion on cleaning both compartments...

On 2020-11-07 - by (mod) -

Mark

That all sounds as if the float control is not working properly; if you are sure that the float itself is never being obstructed or getting stuck then I would replace the switch itself. Leaving a pump running dry can damage a pump bearing or pump impeller. A result is pump failure.

On 2020-11-07 by MARK

Pump to sand filter sporadic.. Works for months then alarm goes off & stops pumping.
Go out fidget with it & it works again.. (I think the float was stuck)
This time after pumping gray water out, the pump stays on.. Is it normal for the pump to stay on, if so.. Will it hurt pump that has no water on impeller? And why would it stay on?
Or should pump stop after pumping all liquids out??
Thank you so very much..

On 2020-10-09 by Paul S

When my septic tank was installed, no riser was installed above the "liquid" part of the tank and a sidwalk now covers that portion of the tank. I have a pump tank following the discharge from the septic tank because I have to pump up hill to the drain field. In this configuration, how important is it to pump the "liquid" side of the septic tank?

On 2020-10-01 by Sharon S

Yikes! Thanks for the great article. I wish I would have read this article a decade ago! We are (were) totally naïve to septic systems. I have an appointment to get ours pumped in a few days It will be the first time since we bought the house 12 1/2 years ago.

It's just my husband and I with a 1250 gal tank. We took the lid off yesterday and the scum layer seems REALLY thick (although I didn't actually measure it.)

How do I know if my drain fields have been compromised/are clogged up at all?

We added a bonus room a few years ago and had it plumbed for a bar sink. Those pipes are not capped off and within the last week, I have noticed a bad odor in this room. I'm thinking it is coming from those uncapped (but taped over) pipes. Everything else seems fine. Nothing coming out of the ground.

Drains all work great. Crossing my fingers that we didn't wait too late and will definitely add this to a regular maintenance schedule moving forward.

On 2020-08-28 by rick

can a system be too big...if not enough use, what happens inside the chambers? putting in system soon. planning for 4 bedrooms through 3 building, two, 200sqft cabins and a larger 600 sqft apt. this may not happen right away, 2-3 yrs maybe with just a 200 sqft for the first 2-3 yrs.

On 2020-08-11 by Anthony G.

Outside of the comments I had written below, both from the actual owner's manual and a rep. that had returned my call from Delta Environmental (manufacturer), I read they should clean the clarifier walls and partially fill the tank, not let the tank run dry, leave the ATU air compressor running. I did see a note that states "repeat step 3 to skim off floatable solids on the surface of the clarifier and lower to the bottom of the clarifier" this is to be done after the rinse off. Perhaps with this extra stage that would indicate a full cleanout after the wash down.

On 2020-08-11 - by (mod) -

Anthony

Thank you for helpful question.

I don't know the answer.

Let's both do some reading on the system you describe and report back here on what we can find.

On 2020-08-11 by Anthony G.

Hello - thanks for the web tips. Our Whitewater DF-50 owners manual on page 12 states: "Pump out 80 to 90% of the ATU." I did locate on your site to pump out the entire tank." Might you have further information as to why Delta Environmental recommends leaving some solids and why your site recommends a full clean out? Thanks

On 2020-01-12 - by (mod) -

Anon:

"Can" means 1. is one physically able to do something, or if one is a lawyer, it might mean "2. legally permitted"

answer 1, of course, but it would make not a shred of economic sense. Answer 2 - dubious, possibly deceptive.

But it would not make a shred of sense economically as the pumper has got to charge double to come back and do the job right.

Furthermore, until a septic tank is FULLY emptied, most-likely you're leaving the settled sludge and much of the floating scum that are the most-important components to remove.

Just pumping half the liquid buys you nothing.

On 2020-01-12 by Anonymous

can I have only half of tank pumped due to landlord for closer

On 2019-12-11 - by (mod) -

This sounds very strange, Jeremy; I have to GUESS that your tank has no bottom has leaks in sides near the bottom such that it's leaking out into the surrounding soil

Is this a concrete tank or steel or what?

On 2019-12-04 by Jeremy

Septic pumping company came today. They said there was only 4 inches of water in the tank. Lost pumping of my septic system was four years ago by same company. Where is all my waste form the last four years. They did not pump tank due to it not having but the four inches of water.

On 2019-11-25 - by (mod) -

Joe

Thanks for the question:

be sure to review HOME BUYERS GUIDE to SEPTIC SYSTEMS

https://inspectapedia.com/septic/Septic_Tank_Guide_for_Home_Buyers.php

Certainly there is good information to be found also by pumping a septic tank and inspecting before, during and after that process but NOT before the system receives its initial inspection and test.

On 2019-11-24 by Joe

I'm looking to buy a new house. It was built in 2007 and has a 1000 gallon tank in looking to more info about the exact specifics but they said it has never been pumped. I'm concerned about that. What should I have my inspector look for. I was gonna have them drain it before inspection but reading your info that doesnt soumd smart. Should I jave it pumped prior to inspection. Thanks in advance

On 2019-04-21 by hhswimming1

Never mine regarding my question. I continued my reading and I found the answer that I was looking for. Looks like 1/3 full and also additional information on where the effluent pipe should be relative to the surface scum. Great information. Thank you.

On 2019-04-11 - by (mod) -

Eco-Tabs are a septic tank additive

Bob:

Eco-Tabs are a septic tank additive that claims to improve the oxygenation treatment in the tank.

I am sorry to have to report that:

1. No septic tank treatment will "cure" or "repair" a failed septic drainfield.

2. Pumping a septic tank will also not ever cure or repair a failed, saturated drainfield.

You need an on-site inspection to accurately diagnose the condition of your septic system - is there a blockage or are the leachfields in failure - if the latter, unfortunately, you probably need to re-build the drainfields.

We discuss septic tank additives in detail at

SEPTIC TREATMENTS & CHEMICALS https://inspectapedia.com/septic/Septic_Tank_Treatments.php

There we include a description of Eco-Tabs as provided by the company, along with company contact information should you want to get their advice.

On 2019-04-11 by Bob Ash

I have Eco Tabs Bio treatment tablets to treat my septic system and waterloged tile bed. My question is should pump out my totaly full to the top, tank before I add my Eco Tabs treatmen tabs?
Thank you

On 2018-12-09 - by (mod) -

To clean a septic tank it is normally necessary only to uncover enough of the tank to expose and safely remove the tank access cover not the entire tank cover. If that requires a lot of digging you may need a hole to be larger to provide safe access without falling into the Tank.

In that case I would add a septic tank riser to make future service easier.

On 2018-12-08 by Anonymous

Do I have to uncover the whole top of the tank or just a section


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