Septic Filters: Guide to Using Septic Filters and Graywater Filters to Protect Drainfields InspectAPedia® -
What are septic effluent filters or septic tank filters?
How using a septic filter can extend the life of the septic drainfield
Signs of a clogged septic filter or clogged drywell filter
Where to add a septic effluent filter if there is no room in the septic tank
Graywater filters for extending drywell life
Septic filter or gray water filter product sources
Questions & answers about buying and using septic filters and graywater filters
This document explains the design and use of various types of septic effluent filter systems and graywater filter systems
to protect the septic drainfield or absorption system from clogging.
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Septic filters are such a significant improvement in
septic system operation and longevity that some jurisdictions (such as Arizona) require them on new septic installations. Also see MEDIA FILTER SEPTIC SYSTEMS for difficult site septic designs, and see septic filter products listed at Septic Filter / Graywater Filter Sources.
Citation of this article by reference to this website and brief quotation for the sole purpose of review are permitted. Use of this information at other websites, in books or pamphlets for sale is reserved
to the author. Technical review by industry experts has been performed and is ongoing - reviewers welcomed and are listed at "References."
The Basics of Using Septic Filters to Extend Septic Drainfield Life
While there are several versions of septic and other types of wastewater filters, the most basic septic effluent filter is a simple tee
and filter installed at the septic tank outlet. The installation can be handled by a septic contractor or a skilled homeowner, and
can cost less than $100. U.S.
Our illustration (left) shows a filter in use in a septic graywater basin.
These simple septic filters, such as greywater filters, washing machine filters, and filters at the effluent outlet
of a conventional septic tank are all designed to protect the septic effluent absorption field or leach field.
Septic filters are placed either in the septic tank at the outlet tee or in a separate chamber outside of and close to
the septic tank.
Graywater filters may be placed at the inlet to a drywell or graywater disposal system. Washing
machine filters are often installed at the clothes washer outlet hose.
We include a list of product sources for these various types of septic filters.
In contrast with septic effluent and graywater filters, media filter septic systems use a conventional septic
tank followed by any of several methods to further filter and treat septic effluent before it is discharged to
the soil, soil surface, or waterway.
Media filter systems are discussed at Using Septic Media Filters as Components of Alternative Septic Systems for Difficult Sites.
Septic Effluent Filters Protect the Leach Field from Clogging
To add protection for the septic absorption system, add a septic effluent or gray water filter at the septic tank outlet tee.
The sketch at page top (US EPA) shows a large basket filter installed at a septic tank outlet.
The photo at left shows
a simple filter which is installed inside the outlet tee of a septic tank.
If there is no room in the tank to install such a filter, a small chamber and filter can be installed outside of the septic tank
but upstream from the drainfield - just like our septic graywater basin and filter shown in the previous sketch..
Although most grease or large solids entering the septic tank are intended to be retained there where they are reduced
to floating scum at the top of the tank or settled sludge at the tank bottom. However septic tank effluent also contains
suspended solids, smaller particles of debris which, as they pass out to the soil absorption system, or drainfield,
speed the clogging of the absorption system and thus shorten its life.
By trapping more of the suspended solids in septic effluent we pass clarified septic effluent to the absorption system,
extending its life. Don't worry about starving the biomat by filtering the septic effluent. There are still plenty of nutrients
in the effluent passing into the absorption system.
A number of companies sell these devices which will add life to your drainfield by reducing the level
of suspended solids flowing out of the tank. If you buy a septic tank outlet filter you'll
see that the filter product will typically be of about the dimensions of the outlet
tee I cited above, or perhaps an inch or two deeper.
See the links below for more information about
septic filters and septic media filter systems.
[Photo courtesy of thenaturalhome.com - see Product Source List below]
Questions & Answers regarding this article
Questions & answers about buying and using septic filters and graywater filters
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Don't Flush these things into a septic system: a list of what's ok and what's not ok to put into septic tanks and building drains
Septic Tank Pumping Frequency Guide for Septic Tanks: When, How, What to Watch For when pumping or cleaning septic tanks
SEPTIC SYSTEM DESIGN ALTERNATIVES New York State Wastewater Treatment Standards - Individual Household Systems, Appendix 75-A (1990), Public Health Law 201(1)(1).
Books & Articles on Building & Environmental Inspection, Testing, Diagnosis, & Repair
Our recommended books about building & mechanical systems design, inspection, problem diagnosis, and repair, and about indoor environment and IAQ testing, diagnosis, and cleanup are at the InspectAPedia Bookstore. Also see our Book Reviews - InspectAPedia.
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), Advanced Onsite Wastewater Systems Technologies.
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 we recommend for professionals--DF.
AEROBIC SEPTIC SYSTEMS
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.
Design Manuals for Septic Systems
US EPA Onsite Wastewater Treatment Systems Manual [online copy, free] 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 Onsite wastewater treatment and disposal systems,
Richard J Otis, published by the US EPA. Although it's more than 20 years old, this book remains a useful reference for septic system designers.
U.S. Environmental Protection Agency, Office of Water Program Operations; Office of Research and Development, Municipal Environmental Research Laboratory; (1980)
"International Private Sewage Disposal Code," 1995, BOCA-708-799-2300, ICBO-310-699-0541, SBCCI 205-591-1853, available from those code associations.
"Manual of Policy, Procedures, and Guidelines for Onsite Sewage Systems," Ontario Reg. 374/81, Part VII of the Environmental
Protection Act (Canada), ISBN 0-7743-7303-2, Ministry of the Environment,135 St. Clair Ave. West, Toronto Ontario M4V 1P5 Canada $24. CDN.
Manual of Septic Tank Practice, US Public Health Service's 1959.
Greywater System Books
The New Create an Oasis With Greywater, Art Ludwig; Buy New: $14.25. Ludwig is one of the most thoughtful, prolific, and sometimes controversial writers on gray water systems and alternative designs. We recommend his book as clear, easy-to-understand writing aimed at property owners who want or need to consider a graywater installation to conserve water, recycle water, reduce water use, or to reduce the load on their septic system. This is the latest edition of this Art Ludwig's greywater design book classic.
Builder's Greywater Guide, Art Ludwig; Buy New: $10.17. Installation of Greywater Systems in New Construction & Remodeling; A Supplement to the Book "Create an Oasis With Greywater" (Paperback).
Quoting a review from Amazon: I recommend that you get the 3 companion books on greywater treatment "Create an Oasis", "Branched Drain Greywater Systems" and "Builder's Greywater Guide". The information in these volumes will keep most of us far more informed than most of the regulators, the system builders, and the experts-in-theory. These volumes are real-world gems. Art Ludwig has cut to the core of wastewater issues. He's obviously done all of his homework, mulled-over the variables, and come up with a common sense, economically reasonable, environmentally responsible approach to wastewater. I expect to save money that I would have spent on a post-septic tank, aerobic unit that would seemingly have been ecologically responsible; but because of the technological overkill, ultimately that system would have defeated my altruistic environmental concerns.
... These books talk the talk and walk the walk better than anything else that I've seen. Buy a set for yourself, a set for your neighbors, and a set for the regulators.
Branched Drain Greywater Systems [superseded by "The New Create an Oasis with Greywater"], Art Ludwig. If you already have this book but are in the process of installing new gray water systems you should take a look at the newer
edition listed first above in this section of our Greywater book recommendations.
You may prefer the newest edition, but there is great information in this older version, perhaps all you need, and these copies are
sold at very low prices - an aid to people of limited means.
Rainwater Catchment Systems for Domestic Supply: Design, Construction and Implementation,
Erik Nissen-Petersen, John Gould. (Mr. Ludwig, while much appreciated, is not the only author providing really useful design guides for graywater systems--DF)
Quoting from an Amazon review: This book reviews the art of roof and ground catchment systems for rainwater. The water collected can be used for household or other purposes. The designs are aimed for individuals with limited access to electricity and/or civic water utilities. The text includes drawings, photographs and step-by-step instructions.
One might say the book is really written for the 'aid worker' since it also considers ethnic and gender issues that would be 'obvious' to the future owners of the the systems.
Guidelines on rainwater catchment systems for Hawaii, (CTAHR resource management publication)
Patricia S. H Macomber. This more technical document may be especially helpful for rainwater collection and recycling systems for climates
where there is heavy rainfall such as demonstrated for Hawaii.
Design for Water: Rainwater Harvesting, Stormwater Catchment, and Alternate Water Reuse, Heather Kinkade-Levario. Quoting from Amazon's review: Design for Water is an accessible and clearly written guide to alternate water collection, with a focus on rainwater harvesting in the urban environment. The book: Outlines the process of water collection from multiple sources-landscape, residential, commercial, industrial, school, park, and municipal systems
Provides numerous case studies, Details the assembly and actual application of equipment, Includes specific details, schematics, and references.
All aspects of rainwater harvesting are outlined, including passive and active system setup, storage, storm water reuse, distribution, purification, analysis, and filtration. There is even a section on rainwater harvesting for wildlife. In addition to rainwater, there are several affordable and accessible alternate sources, including cooling tower bleed-off water, air conditioning condensate, gray water, and fog collection. Design for Water is geared to providing those making development decisions and guidelines with the information they need to set up passive harvesting techniques. The book will especially appeal to engineers, landscape architects, municipal decision-makers, developers, and landowners.
Heather Kinkade-Levario is a land-use planner in Arizona and the author of the award-winning Forgotten Rain. She is president of Forgotten Rain L.L.C., a rainwater harvesting and stormwater reuse company.
The Toilet Papers: Designs to Recycle Human Waste and Water : Dry Toilets, Greywater Systems and Urban Sewage (Paperback) Sim Van Der Ryn, Wendell Berry; Quoting from an Amazon review: With a title like "Toilet Papers" and from a distinguished eco-architect like Sim Van der Ryn, I needed no intro or review to buy a copy of this little, but well researched historical over-view of effluent mitigation and current eco-friendly toilet design. This book is filled with good line drawings and photographs to depict everything from the historical perspective to the current dry toilets and their construction..
Quality issues in harvested rainwater in arid and semi-arid Loess Plateau of northern China,
K. Zhu, L. Zhang, W. Hart, M. Liu, H. Chen (out of print, find by search and deferred order).
Amazon's description may be helpful: Loess soils cover vast areas in the arid and semi-arid regions of northern China. Due to the lack of reliable surface water and ground-water, rainwater harvesting has played a prominent role in farmers' domestic usage and agricultural irrigation. An economical and valid type of water storage cistern with optimum design of components has been introduced to rural areas in the Loess Plateau. Different collection alternatives showed apparent variations in rainwater quality. By using different catchments, such as mortar roofs and cement-paved courtyards, compacted land or road surfaces, rainwater can be effectively collected for storage in cisterns. This study focused mainly on the quality of rainwater harvested from the different catchment systems and stored for different periods of time. By analysis of the water samples stored in these cisterns, it was evident that rainwater quality could be improved significantly by self-purification during the storage. With emphasis on rainwater quality affected by the
different catchment systems, it was found that the measured inorganic compounds in the rainwater harvested from roof-yard catchment systems generally matched the WHO standards for drinking water, while the concentrations of some inorganic compounds in the rainwater collected from land and road surfaces appeared to be higher than the guideline values for drinking water, but generally not beyond the maximum permissible concentrations. However, Fecal Coliform, which is an important bacteriological parameter for the three catchment systems, exceeded the limits of drinking water to a greater extend. Trace amounts of 55 organic pollutants were identified, including aliphatic hydrocarbons, aromatic compounds and phthalate esters, etc. The analytical results indicated that roof-yard catchments that included the ''first flush'' usually provided safe drinking water with low organic contents, even for rainwater collected immediately after rainfall. In contrast, rainwater harvested from road surfaces had poor quality
with respect to the organic constituents, regardless of stored time.
City eying home water-recycling technology; uses bath and washer water for irrigation., (ReWater Systems' equipment for greywater irrigation):
This is an article from: San Diego Business Journal [HTML] (Digital) available online in digital format. I have not (yet) reviewed it -- DF
Onsite Wastewater Disposal Books
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
Planting Over Septic System Component", Daniel Friedman (author/editor, InspectAPedia.com), The Innovator, Winter/Spring 2008, BCOSSA, British Columbia OnSite Sewage Association, 201-3542 Blansard St., Victoria BC V8X 1W3 Canada
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.
Test Pit Preparation for Onsite Sewage Evaluations, State of Oregon Department of Environmental Quality, Portland OR, 800 452-4011. PDF document. We recommend this excellent document that offers detail about soil perc tests, deep hole tests, safety, and septic design. Readers should also see Soil Percolation Tests and for testing an existing septic system, also see Dye Tests
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.
The NSFC Products List has an excellent list of design manuals/modules available from their website or by telephone 800-624-8301
Submissions welcome. send us a suggested document link or request an exchange of website links