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PLUMBING SYSTEM INSPECT DIAGNOSE REPAIR
AGE of PLUMBING MATERIALS & FIXTURES
AIR DISCHARGE at FAUCETS, FIXTURES
BACKUP PREVENTION, SEWER LINE
BLOCKED DRAIN REPAIR METHODS
CARBON MONOXIDE - CO
CHECK VALVES, WATER SUPPLY
CHLORINE IN SEPTIC WASTEWATER
CLEANOUTS, PLUMBING DRAIN
CLOGGED DRAIN DIAGNOSIS & REPAIR
CLOGGED SUPPLY PIPES, DIAGNOSIS
CLOGGED SUPPLY PIPES, REPAIR
CLOGGED SUPPLY PIPES, HOT WATER
CONDENSATION or SWEATING PIPES, TANKS
CROSS CONNECTIONS, PLUMBING
DEBRIS in WATER SUPPLY, Water Heater
DEPTH of DRAIN & SEWER PIPES
DEPTH of SEPTIC TANK
DRAIN & SEWER PIPING
DRAIN LINE DEPTH
DRAIN a WATER HEATER TANK
FLOOD DAMAGE ASSESSMENT, SAFETY & CLEANUP
FLOODED HEATING EQUIPMENT REPAIR
FLOODED SEPTIC SYSTEMS, REPAIR
FLOODED WATER HEATER REPAIR
FLOOR DRAIN / TRAP ODORS
FLUSHOMETER VALVES for TOILETS URINALS
GAS PIPING, VALVES, CONTROLS
GALVANIC SCALE & METAL CORROSION
GALVANIZED STEEL PIPING
HARD WATER - SOFTENERS
HEAT TAPES, Heat, Insulation prevent Freeze-Up
LEAD POISONING HAZARDS GUIDE
METHANE GAS SOURCES
MIXING / ANTI-SCALD VALVES
MUNICIPAL WATER PRESSURE IMPROVEMENTS
NOISE CONTROL for PLUMBING
NOISE, PLUMBING DRAIN DIAGNOSIS
NOISE, PLUMBING DRAIN REPAIR
NOISE, PLUMBING CHECKLIST
ODORS GASES SMELLS, DIAGNOSIS & CURE
ODORS IN WATER
ODORS, SEPTIC or SEWER
ODORS SEWER GAS in COLD WEATHER
ODORS, SULPHUR SMELL SOURCES
OUTHOUSES & LATRINES
PIPING IN buildings, Clogs Leaks Types
PLUMBING FIXTURES, KITCHEN, BATH
PLUMBING NOISE CONTROL
PLUMBING VENT DEFINITIONS & CODES
PLUMBING VENT DEFECTS & NOISES
PUMPS, WATER REPAIR
REPAIR BURST LEAKY PIPES
SEPTIC SYSTEM INSPECT DIAGNOSE REPAIR
SEWER BACKUP PREVENTION
SEWER GAS ODORS
SEWER LINE REPLACEMENT
SEWAGE BACKUP, WHAT TO DO
SEWAGE BACKUP TEST & CLEANUP
SEWAGE BACKUP PREVENTION
SEWAGE BACKUP TEST & CLEANUP
SEWAGE & SEPTIC CONTAMINANTS
SEWAGE CONTAMINATION in buildings
SEWAGE CONTAMINANTS in FRUIT / VEGETABLES
SEWAGE EJECTOR / GRINDER PUMPS
SEWAGE NITROGEN CONTAMINANTS
SEWAGE PATHOGENS in SEPTIC SLUDGE
SEWAGE PUMP CLOG DAMAGE
SEWER BACKUP PREVENTION
SEWER GAS ODORS
SEWER LINE REPLACEMENT
SHUTOFF VALVE LOCATION, USE
SULPHUR & SEWER GAS SMELL SOURCES
SUMP PUMPS GUIDE
SWEATING (CONDENSATION) on PIPES, TANKS
TOILETS, INSPECT, INSTALL, REPAIR
TOILET FLUSHOMETER VALVES
TOILET INSTALLATION PROCEDURE
TOILET OVERFLOW EMERGENCY
TOILET PLUGS, SEWER BACKUP
TOILET REPAIR GUIDE
Toilet Types, Flush Methods
TOILETS, DON'T FLUSH LIST
TRAPS on PLUMBING FIXTURES
WATER HAMMER NOISE DIAGNOSE & CURE
WATER ODORS, CAUSE CURE
WATER PIPES, Clogs Leaks Types
WATER PRESSURE & FLOW MEASUREMENT
WATER PUMPS, TANKS, TESTS, WELLS, REPAIRS\
WATER QUALITY TESTS, CONTAMINANTS, TREATMENT
WATER QUANTITY IMPROVEMENT
WATER SHUTOFF VALVE LOCATION, USE
WATER SHUTOFF VALVE, WELL PUMP
WATER SOFTENERS & CONDITIONERS
WATER SUPPLY & DRAIN PIPING
WATER TANK: USES, TROUBLESHOOTING
WATER TESTS, CONTAMINANTS, TREATMENT
WATER TREATMENT EQUIPMENT CHOICES
WELL PUMP PRIMING PROCEDURE
WELLS CISTERNS & SPRINGS
WINTERIZE A BUILDING
How to fix a blocked or clogged drain: this article series explains how to troubleshoot & repair slow or blocked plumbing drains, diagnose & fix sewer line or septic system backups & how to distinguish between a probable septic system failure versus a probable blocked building drain or sewer line. When a building drain or main sewer line is clogged or slow, or when there is a septic system backup, it's important to determine where the problem lies, since the repair steps can be quite different and costs can vary widely. Here in addition to a text-based explanation of how we diagnose blocked drains or related sewer line or septic system problems, we include in a drain & drainfield diagnostic table.
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FIRST SIGNS - What are the First Signs of Trouble Indicating Failure of a Septic System?
What should a building owner do if the building drains stop working or there are odors or sewage-suspect wet areas on the property? It is important to distinguish between a simple blocked trap or blocked pipe and a failing septic system. That's because the remedies, as well as the costs, are quite different.
The photo at page top shows the final repair for a toilet that was backing up - in this case the drain was blocked by a child's underpants. (See TOILET REPAIR GUIDE.) By following the investigative steps we recommend you can determine the difference between a blocked drain and other more extensive plumbing or septic system problems.
Our photo at above-left shows a clogged shower drain in an older home. That white blob of crud in the drain trap may be removed or pushed through by a plumbing snake. But if the building is served by galvanized drain lines, those may be blocked internally by rust or mineral deposits, leading to a more costly repair.
Is it a Plumbing Problem or a Septic System Problem - A First Look
A simple initial step must be taken to distinguish between an in-building plumbing problem and an (outside) on-site waste disposal system problem.
Simply put, if a single building fixture is sluggish or clogged, but if other building fixtures drain properly, you should suspect a local clog or vent problem at the individual fixture.
If all building drains are slow or clogged, or if waste is backing up into the building from the lowest plumbing fixture, you would suspect the onsite waste disposal system.
Details to help you make sure that you know whether the clogged or slow drains or backed up drains are due to a drain blockage rather than due to a failing septic system are provided at CLOGGED DRAIN vs SEPTIC PROBLEM
Diagnose Slow or Clogged Drains: 12 step procedure to diagnose & fix a blocked or slow plumbing drain
Here are twelve easy steps to take, in order, to deal with a clogged or slow drain. In the process we'll discover if the problem is only a blocked pipe or if the septic system is at fault. Before digging up the septic system be sure to go through these steps - it may save you some money.
Note: Some of these plumbing drain clog diagnostic steps attend to distinguishing between a drain problem and a septic system problem. If your building is connected to a sewer system rather than a private septic system, the text in these steps that identifies the location of a problem in drain lines outside the building still apply, as your building sewer line connection between building and sewer main may be in trouble. Of course other features, such as a flooded or failed septic drainfield won't pertain directly, though indeed a municipal sewer can also back up into a building.
Green link shows where you are in this article series.
Also see Camping & Emergency Toilets and also see TOILET ALTERNATIVES for a discussion of camping toilets, chemical toilets, emergency-use toilets, waterless toilets, graywater systems, composting toilets, home health care toilets, incinerating toilets, outhouses, and latrines.
At PLUMBING DRAIN VENTS we explain the basics of proper plumbing vent piping and how errors cause trap siphonage, odors, and noises. We discuss how to diagnose and cure drain sounds at PLUMBING DRAIN NOISE DIAGNOSIS.
Frequently Asked Questions (FAQs) About how to Correctly Diagnose & Fix a Clogged Drain Connected to a Private Septic or to a Public Sewer System
I am wondering how to clear a blocked bathtub drain. The bathtub has not been used for some time and it is blocked with solid buildup from minerals/calcium. I tried a few drain cleaners, scraping at it and boiling water to no avail and ended up bailing the water out. Any suggestions? - M. 1/15/2013
What is the drain piping material? I'm guessing galvanized iron or that + cast iron?
How did you determine that the blockage is from mineral deposits?
I believe it is cast iron piping.
It is connected to a public sewer system.
No, it's not the only slow drain - the bathroom sink is slow as well.
The bathtub is over an unfinished basement- M.
As the drain blockage you describe is just in a single bathroom and not throughout the building, I don't start by assuming it's a system drain problem; more likely a local drain issue; typically we find a combination of cast iron and galvanized iron; sometimes you can clear mineral deposits, even hair and other crud using an aggressive chemical drain cleaner; some plumbers also try using muriatic acid;
Watch out: The risks of using dangerous chemicals to try to open a blocked drain include at least these, in addition to those warnings on the product label:
The best procedure is to follow a series of escalating steps, starting with plunging, snaking if we think it's an actual clog from hair or a single point of debris, trying some drain cleaners (caustics & OTC cleaners dissolve hair, maybe paper, while acids such as muriatic used by a plumber can dissolve mineral deposits), with caution, and ultimately replacing the drain;
I have not had much success with trying to snake drains that are actually blocked by rust or mineral deposits; the crust of iron or minerals is just too hard to be cleared by pushing a wire through the drain, and even a rotary drain cleaner may have trouble attacking such deposits, though you could discuss that option with your plumber.
More often, if that's the problem, and if the chemical does not clear the blockage, at this step it's time to expose the drain lines and think about replacing them.
Detailed advice on proper diagnosis and cure for a clogged drain begins at our 12-steps in the article above,
CLOGGED DRAIN DIAGNOSIS & REPAIR - home page
and continues at
Finally, if you are right that mineral deposits from the water supply (unlikely with municipal water supply) are clogging drains, your building may need a water softener;
Questions & answers or comments about how to diagnose & repair slow or clogged building drains.
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Technical Reviewers & References
Related Topics, found near the top of this page suggest articles closely related to this one.