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SEPTIC SYSTEM INSPECT DIAGNOSE REPAIR
SEPTIC CARE INSTRUCTIONS
SEPTIC D-BOX INSTALL REPAIR
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 & SEPTIC CONTAMINANTS
SEWAGE BACKUP, WHAT TO DO
SEWAGE BACKUP TEST & CLEANUP
SEWAGE BACKUP PREVENTION
SEWAGE CONTAMINATION in BUILDINGS
SEWAGE CONTAMINANTS in FRUIT / VEGETABLES
SEWAGE EJECTOR / GRINDER PUMPS
SEWAGE LEVELS in SEPTIC TANKS
SEWAGE NITROGEN CONTAMINANTS
SEWAGE PATHOGENS in SEPTIC SLUDGE
SEWER GAS ODORS
SEWER LINE REPLACEMENT
SINKHOLES, WARNING SIGNS
SMELL PATCH TEST to Track Down Odors
SOAKAWAY BED FAILURE DIAGNOSIS
SULPHUR & SEWER GAS SMELL SOURCES
TOILETS, INSPECT, INSTALL, REPAIR
ALTERNATIVE & WATERLESS TOILETS
TOILETS, DON'T FLUSH LIST
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 system D box installation, specifications, inspection, diagnosis, and repair:\
In this article series about septic system drop boxes we describe the best procedures for locating and inspecting, repairing or replacing the septic drainfield distribution box, or the "D-box" or "Splitter box".
If the D-box is leaking, smells, or is tipped, clogged, or otherwise not working this article describes how to diagnose & fix the trouble.
This series of septic system installation, maintenance & repair articles discusses the Inspection and Reporting the Condition of Private Residential Waste Disposal Systems - or - Where Does it Go When I Flush? and ... Will We Meet Again?
Green links show where you are. © Copyright 2014 InspectApedia.com, All Rights Reserved.
Definition of a Septic D-Box: a septic distribution box is a container used to receive septic system effluent from a septic tank and to re-distribute the effluent into a network of attached drain-field or soakaway bed absorption trenches & pipes.
The D-box works by gravity, flowing effluent into the drainfield (or leachfield) piping network.
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Article Series Contents
How far away from the septic tank is the dbox? - Kristin Clary
How far from the main tank is the D box located on average? - Fishass
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Reply: Distance from the Septic tank to the D-Box:
Kristin & Fishass: there is not a fixed distance from the septic tank to the distribution box; rather, its location depends on the space for and layout of the septic drainfield. But you can often get a fair idea where the D-box is likely to be by any of several means:
The following building code example specification for septic system distribution boxes is excerpted from SEPTIC DISTRIBUTION LINES, BOXES, TYPES, NYS-A.7 Effective Date: 12/01/90 Title: Appendix 75-A.7 - Distribution devices
(1) Distribution Box Design Specifications - the D-Box Specs
Continue reading at SEPTIC D-BOX INSPECTION
The distribution box (more than one may be in use) connects a single effluent line from the septic tank to a network of absorption system components such as drainfield leach lines or to a network of seepage pits or galleys.
Details are now at SEPTIC D-BOX INSPECTION
Question: are the pipes from the D-box solid or perforated?
Reply: It depends on septic drainfield layout.
Details are now at SEPTIC D-BOX PIPING
Reader question: I am being told that my D box is bad. When no levelers are in place all effluent runs into only one port.
Reply: Details about thorough inspection and diagnosis of Drop box problems are now at SEPTIC D-BOX TROUBLESHOOTING
Reader Question: water is leaking out of my distribution box. Should the lid be sealed?
Reply: Details about flooding, leaks and odors at the drop box are now at SEPTIC D-BOX FLOODING
Question: How to repair a bad D-box lid or cover
My D box lid has failed and the sides are starting to crumble.
Reply: Details about septic drop box covers have been moved to SEPTIC D-BOX COVERS
Reader Question: My d box is damaged, can I just eliminate it and plumb directly to the leach field lines?
Reply: yes but just in emergency - it's better to replace and set the D-box properly.
Details are now at SEPTIC D-BOX TEMPORARY REPAIR
Reader Question: What's the difference between a septic system D-box and a Splitter?
Reply: Basically there is no difference in function between a D-box and a Splitter box.
For details about drop box splitters and drainfield resting and recovery or Drainfield R&R approaches see SEPTIC D-BOX SPLITTERS
Continue reading at SEPTIC D-BOX INSPECTION or select a topic from the More Reading links shown below.
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Frequently Asked Questions (FAQs)
Question: Repairman says hard water will ruin my water treatment system and drainfield
I have hard water and treat it with a culligan system. My neighbor had a title five and needed to have his D-box replaced to pass. The repairman said the whole street will have the same problem because of hard water will my treated water system help or hurt my system - Kevin 9/29/12
How do they test for Title 5?
And it doesn't quite make sense to me for your repairman to say that hard water will damage your water softener. The purpose of the water softener is to treat hard water. That's its job.
Question: how often should the soakaway bed / septic field distribution box be checked?
(July 15, 2014) Anonymous said:
Good question, Anon, for which I've not found an authoritative answer for these reasons:
OPINION: The need for & frequency of inspection of the D-box would vary by septic system design, local soil properties, level of usage. For example in a system design that uses manually-set alternating soakaway bed field trenches the frequency would be at least that of the planned swap between fields - perhaps every 5 years.
Most people ignore the D-box and never look there until there is a sign of trouble. Then the box is located, opened and inspected for evidence of the septic field condition. That's when defects such as tipping, leaks, or uneven outlet distribution are more likely to be discovered.
If I were to propose a D-box inspection frequency I'd suggest
1. Inspect any time there is other evidence of a septic system backup, failure, or effluent breakout
2. Inspect the D-box on a frequency specified by the septic system designer - if any was specified. For example alternating bed septic systems that use a pump or siphon system may specify annual inspection to check for equipment malfunction or for adjustment.
3. Inspect at the frequency of required drainfield area exchange / rest / modification
4. Inspect at 5-10 year frequency in other conditions
Question: sewage does not flow uphill
(Aug 25, 2014) Charlie said:
Was able to clean everything out and fix the broken line, however discovered that the D-Box is actually uphill from septic tank. It also appeared that the pipe was possibly cracked even before I hit it. Their was a lot of black soil underneath the break. My guess is it happened 10 years ago when the original irrigation system was put in.
I know the tank is not full, so my question is what caused all the sludge build up in the pipe? Was it cracked pipe, the uphill grade, or the plugged D-Box?
Oh for pete's sake: who the heck put the D-box uphill from the septic tank? The proverbial expression is "S_it doesn't flow uphill"
That would leave sludge in the pipe.
Question: flooding seen at the D-box
(Jan 6, 2015) Jamie Steele said:
So a couple of days later we dug up the d-box. When we got to the lid on the dbox a hole accidentally was knocked into the lid and water started coming up from the dbox (the lid subsequently fell apart so a new had to be made). We pumped the dbox out but there were no solids in the dbox. We snaked the line from the septic tank to the dbox as well as both distribution lines and found no blockages of any kind.
Then 3 days of solid rain hit the area and we basically pumped on a regular basis to keep the hole from filling up with water.
What you describe is an illustration of why pumping a septic tank will not fix a septic backup problem. All it does is buy some time - until the tank is filled again, which could be hours or days. The backflow out of the D-box shows that the drainfield is saturated = flooded - not working.
Question: solids in the D-box or septic distribution box
20 January 2015 Gillian Andrew said:
In normal conditions a septic tank is always "full" - to the bottom of its outlet pipe. Pumping won't fix a thing though it may give a few days of relief.
If the drainfields are flooded the system needs replacement or repair or surface water or runoff diversion away from the soakaway beds.
If the D-box is full above its outlet levelers that's another clue that the fields are saturated.
If the D-box contains solids that's more disturbing news as it suggests that the septic tank outlet baffle is damaged or lost. Pushing solids into the soakbed significantly shortens its further life.
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