DYE TEST WARNINGS - Septic Inspection & Loading/Dye Test Warnings
Although septic system inspection & testing can often find a costly failure, unsafe conditions, or other improprieties,
the procedures cannot find all possible septic system problems. So by itself, that is without an expert visual inspection and possibly further investigation at the septic tank, D-box, and even the drainfields, a dye test is not indicative of complete condition of the system.
On the other hand, experienced inspectors have found found so many failed septic systems with
this septic loading and dye test procedure that it's well worth performing and it offers an inexpensive way to detect many expensive problems.
Weak Septic Dye or Inadequate Amount: Some septic dye tablets, such as "Trace-A-Leak Tablets" may have
These tablets are used by some inspectors for septic loading & dye tests.
However it is unlikely that they are a reliable indicator of surface
breakout or seepage.
While individual tablets will dissolve in 1-3 minutes,
they produce a yellow-green dye which may be difficult to see in grassy
areas. Worse, individual tablets produce dye in concentrations of
1 ppm/50 gallons of water. In order to stain a 1000-gallon septic
tank to produce visible output in the fields, at least 200 such tablets
would be required. Tablets are packaged in bottles of 100. A few
tablets, therefore, would in my opinion produce an unreliable test.
Watch out: Wrong septic dye insertion location or wrong water loading location: at SEPTIC FAILURE LAWSUIT we describe an unfortunate case of a buidling inspector who was sued for performing an incompetent septic loading and dye test.
The inspector used an inadequate amount of septic dye to possibly show up a septic system failure should effluent breakout occur, and worse, he ran water in a washing machine drain standpipe (photo at left) that drained into a separate drywell rather than into the septic system.
The morning after the new owners moved into the recently-inspected and tested home, sewage effluent was flowing across the property.
Even a casual inspection of the visible plumbing pipes in the building made obvious that the septic test water was not likely to be entering the main building drain. The inspector lost the case not because it was certain that a proper test would have disclosed a failed septic system, but rather because the test was so incompetently performed that the test had no chance whatsoever of finding a failed septic system.
The home buyer didn't expect a guarantee that a failed septic system would be found, but he had been hoping for a chance at that discovery.
Beware of Bleach: we've encountered a number of instances in which the seller or real estate agent
was attempting to assure a satisfactory water coliform test by shocking the well just before a home inspection - in some
cases just minutes before arrival of the inspector.
Not only is such an act likely to be a commission of actionable
fraud, but it may do more than "hide" a well sanitation issue. If a large amount of bleach has been placed into the
septic tank it is possible for dye entering the system to be bleached colorless. If there is ready access to the
septic tank entry port, observe the septic dye entering the tank and confirm that it's not becoming colorless
at the instant of entry there.
A simple HACH test can also check for the presence of bleach in the
water supply or in suspected bleached-effluent.
This problem is discussed in more detail at CHEATING ON WATER TESTS - Water Test & Septic Test Cheating Warnings for Home Buyers and Home Inspectors.
Four grams of 12% bleach will remove the coloration of one gram of septic dye in solution according to Tramfloc Inc.
Flush the toilet once BEFORE you put in the dye: this dye stains carpeting
and hands; if you put in the dye and the toilet overflows rather than draining
it's a terrible mess.
Certification: WARNING: in some jurisdictions, there are existing septic system inspection
procedures and in some cases inspector training/certification are required.
In some jurisdictions the inspection procedure does *NOT* include the
introduction of dye nor system loading with extra water volume.
Cesspools can obscure or prevent effective septic loading and dye testing::
If a cesspool is in use at a property a septic dye test would not be a reliable indication of good system condition
since the test could simply be trying to fill a large near-empty hole in the ground;
yet such a system may fail soon after being returned to active or heavier regular use.
Cesspool SAFETY WARNING: watch out for cave-ins, keep away: cesspools, particularly older site-built
cesspools present a very high risk of collapse from an unsafe cover or following some types of service involving
pumping, aeration, or hydro-jetting.
Adults or children should not walk over or even near cesspools because of
the risk of falling-in followed by collapse, a virtually certain cause of death. If the presence of a cesspool
is known or suspected at a property its location should be roped off to prevent access and it should be investigated by a professional.
Drywells can obscure or prevent effective septic loading and dye testing: If a drywell system is installed, running water at the fixtures draining into this system
(as may be done by some septic tests) are likely to fail to perform a loading test on the septic system even if such a test was attempted.
First, the fixtures where water was run in attempt to test the septic system (tank and leach field) may not even be delivering
water to those components if instead the fixtures drain to a separate drywell.
It is critical to trace building drains as part of
a septic test or to otherwise try to determine if the test water is actually entering the septic system.
Failed Septic System - Additional Warnings:
The onsite waste disposal system at a property with a failing or failed system is unsanitary and risks contamination of local ground water or wells.
According to the United States Environmental Protection Agency, failed septic systems are the most frequently reported cause of groundwater contamination.
Once a septic system stops treating the raw sewage it not only begins to contaminate the groundwater supplies, it also begins to contaminate
the surrounding soil as well.
High groundwater or deep septic effluent release:
Systems which release septage effluent at deeper levels in the soil (below 24"), such as cesspools and seepage pits,
may successfully "dispose" of the effluent (in that it is not visible to the property occupants) but are unlikely to
successfully "treat" the effluent to make it sanitary.
While such systems may appear to be "working" and may remain unregulated by
local health officials, they are likely to be contaminating nearby ground water, streams, and possibly the drinking water supply.
Mound Systems and Dosing Systems WARNING: mound system using a pumping station are often designed to use
pressure dosing, pumping water to the mound at intervals, usually once per day.
Timed application of septic effluent & dye allows the mound to rest and prevents unnecessary clogging
in the distribution system by maintaining aerobic conditions. Overloading of
these systems during testing could damage the septic system.
Maximum sewage loading rate to trench and bed in gallons per square foot per
day varies depending on soil percolation rate but ranges from .025 to 1.75
GPFD, with the lower numbers for beds than for trenches. (Ref. 14.)
Pumping tank working capacity is (typically) 25% of the daily sewage volume; actual tank
capacity should be much larger than this, at least one day's sewage volume.
Driving heavy vehicles over the mound can damage or destroy it. Typical mound
life is 20 years.
During testing watch closely for seepage at the perimeter or "toe" of the
We recommend limiting the test volume on mound systems to the pumping tank
working capacity. This might be as small as 125-150 gallons.
Trees and stumps may have been disposed-of below the area to be filled as a septic mound. This
"disposal" helps the builder by adding volume and saving on trucked-in fill to form the absorption system.
If you see tree trunks extending out from the base of a septic mound this condition is likely - and improper.
Pumping a Septic Tank Before Testing:
Do not permit the septic tank to be pumped before the septic loading and dye test - that
will prevent a valid test of the system and in particular, prevents loading of the drainfield.
More details about the problem of septic tank pumpouts as a cover-up of a septic problem or failure
are at Don't Pump Before Testing Septic Systems:
warnings for home buyers about septic tank pumping.
Replaced Septic Tanks: When a septic tank has been replaced but connected to an older existing leach field there is increased risk that
problems with the previous (failed) tank may have pushed solid waste into the leach field before the tank problem was discovered.
If this is the case, which would be common, one should expect that even if the leach field did not fail during a loading and dye test,
its future life will be more limited than otherwise.
Steel septic tank warnings: older septic systems often used steel tanks which eventually rust out and have to be replaced.
A damaged tank can also result in costly damage to the leach field or seepage pits.
Opinions of steel tank life range from 15-30 years. If a property is served by an old steel tank it could require replacement at any time.
SAFETY: Child or Adult Safety Hazard: If an older steel tank (or a home-made system) is found or suspected to be present the owner should immediately
protect the area over the tank from access: rotted or rusted covers can collapse and a child or adult can fall into the tank -
an event which can be fatal. Also, watch for and investigate any areas of soil subsidence quickly.
Other Septic Dye Test Limitations: Dye can identify certain kinds of septic failures, but not others.
By itself a dye test is not indicative of overall condition of the system. The
probable locations of tank and absorption system are inspected before, during,
and after a loading or dye test if these were ordered.
Ground conditions such
as snow, ice, leaf cover, can make it impossible for the inspector to see
dye-colored water even if it is leaking to the surface. Reasonable care was
used in determining the location of the components.
However because these
components are buried, no guarantee can be made regarding the location nor
condition of private waste system components unless specific additional tests,
involving opening tank, pumping, and possibly excavation, are ordered. These
tests are not usually part of a home inspection unless preliminary examination
shows an apparent problem.
These pages are part of our SEPTIC DYE TEST PROCEDURE for testing septic system function.
Technical review by industry experts has been performed and is ongoing - reviewers are listed at REFERENCES. Comments and suggestions for content are welcome.
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Questions & answers or comments about mistakes or even catastrophes that might occur or might be detected during a septic inspection & dye test.
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Mark Cramer Inspection Services Mark Cramer, Tampa Florida, Mr. Cramer is a past president of ASHI, the American Society of Home Inspectors and is a Florida home inspector and home inspection educator. Mr. Cramer serves on the ASHI Home Inspection Standards. Contact Mark Cramer at: 727-595-4211 mark@BestTampaInspector.com
John Cranor is an ASHI member and a home inspector (The House Whisperer) is located in Glen Allen, VA 23060. He is also a contributor to InspectApedia.com in several technical areas such as plumbing and appliances (dryer vents). Contact Mr. Cranor at 804-747-7747 or by Email: firstname.lastname@example.org
Home Inspection Education Home Study Courses - ASHI@Home Training 10-course program. Special Offer: Carson Dunlop Associates offers InspectAPedia readers in the U.S.A. a 5% discount on these courses: Enter INSPECTAHITP in the order payment page "Promo/Redemption" space. InspectAPedia.com editor Daniel Friedman is a contributing author.
The Home Reference Book, a reference & inspection report product for building owners & inspectors. Special Offer: For a 10% discount on any number of copies of the Home Reference Book purchased as a single order. Enter INSPECTAHRB in the order payment page "Promo/Redemption" space. InspectAPedia.com editor Daniel Friedman is a contributing author.
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The Illustrated Home illustrates construction details and building components, a reference for owners & inspectors. Special Offer: For a 5% discount on any number of copies of the Illustrated Home purchased as a single order Enter INSPECTAILL in the order payment page "Promo/Redemption" space.
The Horizon Software System manages business operations,scheduling, & inspection report writing using Carson Dunlop's knowledge base & color images. The Horizon system runs on always-available cloud-based software for office computers, laptops, tablets, iPad, Android, & other smartphones.
Pennsylvania State Fact Sheets relating to domestic wastewater treatment systems include
Pennsylvania State Wastewater Treatment Fact Sheet SW-161, Septic System Failure: Diagnosis and Treatment
Pennsylvania State Wastewater Treatment Fact Sheet SW-162, The Soil Media and the Percolation Test
Pennsylvania State Wastewater Treatment Fact Sheet SW-l64, Mound Systems for Wastewater Treatment
Pennsylvania State Wastewater Treatment Fact Sheet SW-165, Septic Tank-Soil Absorption Systems
Document Sources used for this web page include but are not limited to: Agricultural Fact Sheet #SW-161 "Septic Tank Pumping," by Paul D. Robillard and
Kelli S. Martin. Penn State College of Agriculture - Cooperative Extension, edited and annotated by
Dan Friedman (Thanks: to Bob Mackey for proofreading the original source material.)
Books & Articles on Building & Environmental Inspection, Testing, Diagnosis, & Repair
The Home Reference Book - the Encyclopedia of Homes, Carson Dunlop & Associates, Toronto, Ontario, 25th Ed., 2012, is a bound volume of more than 450 illustrated pages that assist home inspectors and home owners in the inspection and detection of problems on buildings. The text is intended as a reference guide to help building owners operate and maintain their home effectively. Field inspection worksheets are included at the back of the volume. Special Offer: For a 10% discount on any number of copies of the Home Reference Book purchased as a single order. Enter INSPECTAHRB in the order payment page "Promo/Redemption" space. InspectAPedia.com editor Daniel Friedman is a contributing author.
Or choose the The Home Reference eBook for PCs, Macs, Kindle, iPad, iPhone, or Android Smart Phones. Special Offer: For a 5% discount on any number of copies of the Home Reference eBook purchased as a single order. Enter INSPECTAEHRB in the order payment page "Promo/Redemption" space.
Grass is Always Greener Over the Septic Tank, Bombeck, Erma: $ 5.99; FAWCETT; MM;
This septic system classic whose title helps avoid intimidating readers new to septic systems, is available new or used at very low prices.
It's more entertainment than a serious "how to" book on septic systems design, maintenance, or repair. Not recommended -- DF.
US EPA Onsite Wastewater Treatment Systems Manual Top Reference: US EPA's Design Manual for Onsite Wastewater Treatment and Disposal, 1980, available from the US EPA, the US GPO Superintendent of Documents (Pueblo CO), and from the National Small Flows Clearinghouse. Original source http://www.epa.gov/ORD/NRMRL/Pubs/625R00008/625R00008.htm
Water Wells and Septic Systems Handbook, R. Dodge Woodson. This book is in the upper price range, but is worth the cost for serious septic installers and designers.
Quoting Amazon: Each year, thousands upon thousands of Americans install water wells and septic systems on their properties. But with a maze of codes governing their use along with a host of design requirements that ensure their functionality where can someone turn for comprehensive, one-stop guidance? Enter the Water Wells and Septic Systems Handbook from McGraw-Hill. Written in language any property owner can understand yet detailed enough for professionals and technical students this easy-to-use volume delivers the latest techniques and code requirements for designing, building, rehabilitating, and maintaining private water wells and septic systems. Bolstered by a wealth of informative charts, tables, and illustrations, this book delivers: * Current construction, maintenance, and repair methods
* New International Private Sewage Disposal Code
* Up-to-date standards from the American Water Works Association