Septic System D-Box Problem Diagnosis
Inspect, Test & Fix Septic System Distribution Box leaks, odors, malfunction
SEPTIC D-BOX TROUBLESHOOTING - CONTENTS: signs of septic system trouble that show up at the drop box. Simple repairs at the D-Box can improve septic drainfield performance and may eliminate septic odors. Tipped D-box, D-Box Leaks, D-Box Odors
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Diagnose problems at the septic system drop box: procedures for troubleshooting leaks, smells, or backups & flooding in the septic system D-box.
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.
Reader Question: Tipped septic effluent distribution box, standing water at end of one leach line
I am being told that my D box is bad. When no levelers are in place all effluent runs into only one port.
I have been told that the way that fitting is angled down low and how it comes in angled is bad. It is making me worried. I am essentially being old that it should be redone.
We have Type III soils, very sandy with 2 - 75' long infiltrators.
Three years ago during the wet season I noticed some standing water at the end of one of the laterals.
It was the lateral that receives all the effluent when no levelers are in place. - Nicholas Day
We were not sure from the two photos but the D-box looks small, and as if it has been invaded by sewage (suggesting the tank was not pumped on schedule or your tank baffles may be bad).
With thanks to clarifications from reader Doug (March 2013), we recap the effluent distribution piping connections to this D-box as follows:
At left: the down-facing elbow marks the effluent inlet to the D-box. The elbow is intended to prevent effluent from short-circuiting through the box to the opposing outlet. The downward pointing effluent promotes even flow through the box and into the two outlets.
Without the elbow, effluent flows more forcibly across the box and into the opposing outlet, but very little effluent will make the 90-degree turn into the perpendicular outlet. This is a very common installation practice
We can see at least two effluent outlets, at the photo's top and bottom. There could have been a third outlet at the right end of the box - one can't quite see for sure. If you look closely at the photo [click to enlarge this or any InspectAPedia image], you can see the teeth on the adjustable outflow limiter, which is installed almost flush with the box wall.
If you knew for example that one of your lines was much longer than the other, you'd send more effluent to the longer line - presuming they are both working ok.
As you report that one of the laterals showed a sign of failure during wet weather several years ago, you might want to try to re-balance the effluent flow sending more (or perhaps temporarily, most) of the effluent into the other drainfield line. But to have an accurate idea of the condition of the drainfield sections or leach lines before adjusting the effluent flow in your D-Box, the best step would be to carefully excavate near the end of each of the two leach lines (presuming you don't already have inspection ports installed). Look at the condition of the soils there, particularly, look for standing water or effluent.
Because the D-box is a small thing and not deep, it shouldn't be a big job nor too costly to dig it out, install a larger one, make sure the D-box is not tipped, and that effluent is flowing as desired into both of the drainfield lines.
But you should also check the septic tank condition, especially the outlet baffle, and the scum/sludge levels, to be sure the tank is pumped on schedule (SEPTIC TANK PUMPING SCHEDULE) and that the baffles are in place and working. (SEPTIC TANK BAFFLES).
Question: during a septic test the trenches "took on water" - they think the D box is kiltered. What does that mean and how do I fix it?
I had a Hydraulic Load test done and the trenches were taking on water...they think the D box is kiltered. Can you explain this and what are the recommendations to have it fixed? - Reen
Reply: a tipped d-box does not distribute effluent evenly among the drainfield lines and can cause flooded drainfields
Sure Reen: someone is making things sound like rocket science instead of simple ditch-digging.
A "kiltered" Dbox is lingo for a "tipped distribution box". As you can read above, the D-box is basically a plumbing junction box that receives incoming effluent from the septic tank and routes it out to multiple drainfield lines where the effluent can be further treated and absorbed into the ground. If the D-box is "tipped" that means it's sending too much effluent down just one line (perhaps flooding it) and not enough effluent down other lines (not using them).
Also if surface runoff or ground water is leaking INTO your D-box, that water will add to the septic effluent liquid load and risks flooding and ruining the drainfields.
Question: The d-box is not distributing effluent evenly among my three drywells. Is it likely to be a tipped d box or a clog?
I have an old 3-drywell system fed from a d-box in the center of the 3 drywells (laid out on 3 points of an equilateral triangle). The system has had minimal use but one drywell is full and the other 2 are bone dry. Should they all be being fed in parallel or in series (one fills before the next)? Is there likely a tip or a clog? - Jeff O
Reply: Drywells are often installed and fed in series; if yours are in parallel, set the D box to send effluent to all of them.
Often drywells were installed in series - not in parallel. If that's how yours were piped, then if you can confirm that the full drywell has an outlet pipe that drains into the next (dry) one in the series you should be OK. If that connection is missing I'd add it.
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 Thanks to reader Nicholas Day for discussing D-box troubles and repairs, September 2010
 Zoeller Pump Company, 3649 Cane Run Rd., Louisville, KY 40211, Phone: 1-800-928-7867, 502-778-2731
Fax: 502-774-3624. Technical support and/or quote related emails: firstname.lastname@example.org. Zoeller produces just about every kind of septic, sewage, effluent, grinder, and sump pump. Homeowners who need a sewage pump are asked to contact their local representative or retail sales outlet. Zoeller classes their pumps into these categories:
Grinder pumps, such as Zoeller's 810/815 Turnkey Grinder Systems, 800-series Grinder Pumps, Cold-Climate grinder pumps, Simplex prepackaged grinder pump systems, and Simplex and Duplex (two pumps) grinder systems including four outdoor use.
Utility, pedestal, & gas engine pumps. These are portable gas-engine powered pumps used typically in construction, service, or emergencies
Sewage & Dewatering pumps, such as certain Aqua-Mate Models and Waste-Mate models, and Sewage-Waste 600-series pumps
Splitter for septic effluent distribution. Web search 5/1/12, original source
https://app.qleapahead.com/rtp/LibraryGet.aspx?asset=85356,63 [copy on file as septic/D-boxes/Zoeller_D-BOx_Splittert.pdf ] Website: www.zoeller.com
Sump, Effluent, Dewatering pumps, such as Water Ridd'r , Mighty-Mate, Aqua-Mate, Flow-Mate, and High Head Flow-Mate pumps - of certain models - be sure to read the manufacturer's intended use for a pump model before purchasing it
 "Drainfield Rehabilitation", Pipeline, Winter 2005, Vol. 16, No. 1, NESC, National Environmental Services Center, 800-624-8301 [copy on file as [/septic/D-boxes/NESC_2005-16_1.pdf
 Advanced Onsite Wastewater Systems Technologies, Anish R. Jantrania, Mark A. Gross. Anish Jantrania, Ph.D., P.E., M.B.A., is a Consulting Engineer, in Mechanicsville VA, 804-550-0389 (2006). Outstanding technical reference especially on alternative septic system design alternatives. Written for designers and engineers, this book is not at all easy going for homeowners but is a text I recommend for professionals--DF.
 Builder's Guide to Wells and Septic Systems, Woodson, R. Dodge: $ 24.95; MCGRAW HILL B; TP;
Quoting from Amazon's description: For the homebuilder, one mistake in estimating or installing wells and septic systems can cost thousands of dollars. This comprehensive guide filled with case studies can prevent that. Master plumber R. Dodge Woodson packs this reader-friendly guide with guidance and information, including details on new techniques and materials that can economize and expedite jobs and advice on how to avoid mistakes in both estimating and construction. Chapters cover virtually every aspect of wells and septic systems, including on-site evaluations; site limitations; bidding; soil studies, septic designs, and code-related issues; drilled and dug wells, gravel and pipe, chamber-type, and gravity septic systems; pump stations; common problems with well installation; and remedies for poor septic situations. Woodson also discusses ways to increase profits by avoiding cost overruns.
 Country Plumbing: Living with a Septic System, Hartigan, Gerry: $ 9.95; ALAN C HOOD & TP;
Quoting an Amazon reviewer's comment, with which we agree--DF:This book is informative as far as it goes and might be most useful for someone with an older system. But it was written in the early 1980s. A lot has changed since then. In particular, the book doesn't cover any of the newer systems that are used more and more nowadays in some parts of the country -- sand mounds, aeration systems, lagoons, etc.
 Onsite Wastewater Disposal, R. J. Perkins;
Quoting from Amazon: This practical book, co-published with the National Environmental Health Association,
describes the step-by-step procedures needed to avoid common pitfalls in septic system technology.
Valuable in matching the septic system to the site-specific conditions, this useful book will help you install a reliable system in
both suitable and difficult environments. Septic tank installers, planners, state and local regulators, civil and sanitary engineers,
consulting engineers, architects, homeowners, academics, and land developers will find this publication valuable.
 Onsite Wastewater Treatment Systems, Bennette D. Burks, Mary Margaret Minnis, Hogarth House 1994 - one of the best septic system books around, suffering a bit from small fonts and a weak index. (DF volunteers to serve as indexer if Burks/Minnis re-publish this very useful volume.)While it contains some material more technical than needed by homeowners, Burks/Minnis book on onsite wastewater treatment systems a very useful reference
for both property owners and septic system designers. We refer to it often.
While Minnis says the best place to buy this book is at Amazon (our link at left), you can also see this book at Minnis' website at http://web page .pace.edu/MMinnisbook
 Septic Tank/Soil-Absorption Systems: How to Operate & Maintain [ copy on file as /septic/Septic_Operation_USDA.pdf ] - , Equipment Tips, U.S. Department of Agriculture, 8271 1302, 7100 Engineering, 2300 Recreation, September 1982, web search 08/28/2010, original source: http://www.fs.fed.us/t-d/pubs/pdfimage/82711302.pdf
 Septic System Owner's Manual, Lloyd Kahn, Blair Allen, Julie Jones, Shelter Publications, 2000 $14.95 U.S. - easy to understand, well illustrated, one of the best practical references around on septic design basics including some advanced systems; a little short on safety and maintenance. Both new and used (low priced copies are available, and we think the authors are working on an updated edition--DF.
Quoting from one of several Amazon reviews: The basics of septic systems, from underground systems and failures to what the owner can do to promote and maintain a healthy system, is revealed in an excellent guide essential for any who reside on a septic system. Rural residents receive a primer on not only the basics; but how to conduct period inspections and what to do when things go wrong. History also figures into the fine coverage.
 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
 Wells and Septic Systems, Alth, Max and Charlet, Rev. by S. Blackwell Duncan, $ 18.95; Tab Books 1992. We have found this text very useful for conventional well and septic systems design and maintenance --DF.
Quoting an Amazon description:Here's all the information you need to build a well or septic system yourself - and save a lot of time, money, and frustration. S. Blackwell Duncan has thoroughly revised and updated this second edition of Wells and Septic Systems to conform to current codes and requirements. He also has expanded this national bestseller to include new material on well and septic installation, water storage and distribution, water treatment, ecological considerations, and septic systems for problem building sites.
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