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SEPTIC SYSTEM INSPECT DIAGNOSE REPAIR
SEPTIC CARE INSTRUCTIONS
SEPTIC D-BOX INSPECTION
SEPTIC DRAINFIELD FAILURE DIAGNOSIS
SEPTIC DYE TEST PROCEDURE
SEPTIC FAILURE SIGNS
SEPTIC INSPECTION & TEST GUIDE
SEPTIC LIFE EXPECTANCY
SEPTIC SUPPLIES & PARTS
SEPTIC SYSTEM DESIGN ALTERNATIVES
SEPTIC SYSTEM DESIGN BASICS
SEPTIC SYSTEMS, HOME BUYERS GUIDE to
SEPTIC SYSTEM SAFETY WARNINGS
SEPTIC TREATMENTS & CHEMICALS
SEWAGE BACKUP PREVENTION
SEWAGE EJECTOR / GRINDER PUMPS
SEWER GAS ODORS
SEWER LINE REPLACEMENT
SINKHOLES, WARNING SIGNS
SOAKAWAY BED FAILURE DIAGNOSIS
SULPHUR & SEWER GAS SMELL SOURCES
TOILETS, INSPECT, INSTALL, REPAIR
TRAPS on PLUMBING FIXTURES
TREATMENTS & CHEMICALS, SEPTIC
VIDEO GUIDES: Septic Videos
WATER CONSERVATION MEASURES
WATER SOFTENERS & CONDITIONERS
WATER SUPPLY & DRAIN PIPING
WATER, WELLS, WATER TANKS: TESTING GUIDE
WASHING MACHINES & SEPTIC SYSTEMS
WASTEWATER TREATMENT BASICS
WINTERIZE A BUILDING
Septic drainfield failure detection & actions when buying a home: this article series discusses how to diagnose and repair Septic Drain Field Failures. We describe common causes of leachfield failures, and we give advice for home buyers or home sellers for the case when a septic failure is discovered during the home sale process.
This article series outlines what goes wrong with septic systems and their various components and describes septic inspection and test methods in detail, explains how to be sure your septic inspection and septic test are conducted properly, tells you where to get more septic system information about a given property, and warns of unsanitary or dangerous site conditions.
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Drainfield or Soakaway Bed Failures: Septic Leach Field Failures that Occur When Buying or Selling a Home
Some septic system repairs are comparatively modest, such as replacing covers or baffles. Replacing septic tanks or leach fields is costly. No leach field has an infinite life, but proper septic system maintenance can defer this cost. Because costly septic system repairs may be upcoming, buyers of properties with a septic system are advised to inspect and test the system before purchase.
Clogged drainfield soils
As we elaborate below, with time and age and normal drainfield functioning, a natural formation of a biomat around the drainfield trench ultimately leads to a thick slime layer that blocks wastewater passage into the surrounding soils.
But failure to pump the septic tank on schedule allows suspended solids and greases to flow into the drainfield, speeding up this clog-up process. Pumping the septic tank on proper schedule (SEPTIC TANK PUMPING SCHEDULE) and use of a septic filter (FILTERS SEPTIC & GREYWATER) are two steps that most add life to a conventional septic tank and drainfield design.
The sketch shows a conventional drainfield trench in cross section. As the drainfield line ages the soils become clogged
around the distribution piping, starting first at the end closest to the septic tank or distribution box.
Flooded Drainfield Soils
A septic drainfield that has become saturated for any reason is no longer functional. Saturated leachfield or soakaway bed soils mean that the wastewater effluent is not being treated by bacterial action and that unsanitary wastewater is being discharged into the environment.
Our photo (left) shows several drainfield failure troubles: flooding over the drainfield and a nearby lake.
Depending on soil conditions, land slope and shape, and perhaps other conditions, a saturated drainfield may not be immediately apparent, but this failure shows up in the following ways:
Building on or over or too close to the leach field causes failures
A leach field can be destroyed by other site "improvements" such as this attempt to install a swimming pool
atop the leaching area in the photo shown at left.
Compacted Soil Drainfield Failures
Compacted soils due to parking or driving on the septic drainfield: driving over the leach field in any vehicle larger than a child's bicycle is a bad idea. Heavy vehicles
may actually crush buried leach field lines, or they may compress the soils around the leach field, either of which leads to failure.
This property actually had no working septic system at all - 100% of its effluent was coming to the surface nearby, brought out by solid rock covered with shallow soils, and running down a steep hill into a local stream.
Paving over the leach field means not functional
But paving prevents both evaporation of effluent (a portion of the effluent disposal method) and it prevents oxygen from reaching the soil, thus inhibiting proper bacterial action needed to treat the effluent.
Green link shows where you are in this article series.
Frequently Asked Questions (FAQs)
Question: D-box flooding indicates a septic field failure in house for sale, I can't afford a new drainfield. How to proceed?
I am having a problem. I am listing my home for sale and had the septic checked out today. The septic company dug up and pumped out the tank with no problems being noticed. He then dug up the D box and inspected it.
When he opened the lid system to the D box the water level was right up to the top of the box. He pumped out the D box and as he was doing that water (clear) was draining back into the D box from the field bed.
We have never had any problems with the septic system, we have it pumped every year since it was installed 18 years ago. The system has never backed up or over flowed on the lawn.
I did notice that the top of the septic tank is only 6" under ground and the top of the D box is 4.5 feet under ground. The distance from the center of the septic tank to the center of the D box is about 21 feet. If you do the math that would produce a 21" per foot pitch. ?
Correct me if I'm wrong but I thought it should only be 1/4 per foot pitch. Please help I cannot afford to install a complete new system. Thank You. - G. 6/19/12
A competent onsite inspection by an expert usually finds additional clues that help accurately diagnose a problem with the septic system, piping, or drainfield. You are describing a flooded D-box and a flooded drainfield. .
If you could look into the Distribution box again and tell me the configuration of the exit lines as well as the layout of the drainfield we could make more sense out of this point. It could be worthwhile, because if 1/3 of the field is doing all the work and is flooded it may be possible to improve the system by temporarily blocking off that drainfield section. More about the septic system distribution box or dbox is at SEPTIC D-BOX INSPECTION.
But if water flows into the D-box from all of the exiting lines, then the entire field is flooded and not working.
How to Avoid a Dispute Between Home Seller & Home Buyer over Septic System Failure
As a home seller, even hating the possible expense and trouble of septic repairs when moving, I would stay away from any cheap magic bullet "repairs".
Like many troublesome and expensive "repairs", septic drainfield or soakaway bed failures lead to a whole industry of magic bullets, most of which do not work at all, the remainder work only temporarily or risk contaminating the environment, and/or are unsupported by impartial expert studies that confirm that the expense produces a lasting repair.
The risk is not only that your magic bullet money is wasted, but more, that you are asking for a later lawsuit by the new owner who will be furious to feel fooled into thinking they were buying a home that was not facing a near term significant expense to replace the drainfield. See SEPTIC DRAINFIELD RESTORERS? for details.
As a home seller I would also stay away from simply finding some fool who is willing to certify that the septic system is functional and does not face a major repair. That too is inviting dispute later when the failure manifests itself and/or the new owner discovers that they face a very costly surprise. Our photo (above left) shows a drainfield failure discovered by a home buyer the morning after moving into their new home. The result was an ugly lawsuit.
Further Exploration Guides What to do About an Apparent Drainfield Failure
If further exploration confirms that we're not facing a blocked pipe (that can be repaired at much lower cost than a whole drainfield), and that drainfield replacement is needed, it would not be a surprise, nor abnormal for an 18-year old field.
You said you cannot afford to install a complete new system. When selling a home, if your attorney agrees, as I expect s/he would, that a seller is obligated to deliver a functional septic system, that does not mean that you personally have to pay for the repairs - the repair can be paid for out of proceeds of the sale of the home. Attorney, contractor, buyer, and seller can work out an escrow or other means to handle that obligation. The wrinkle is that the buyer's bank often won't issue a mortgage for a property without a working septic system. A solution can be a temporary construction loan paid for out of escrow or house sale proceeds.
Also, as a home seller, you should take a look at HOME SELLERS GUIDE TO SEPTIC INSPECT.
Questions & answers or comments about discovering a failed septic leach field or soakaway bed during the purchase of a home - what should a home buyer or home seller do about a failed drainfield?
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