Reverse Osmosis Water Treatment Systems Impact on Septic Tank and Drainfield
The good news is that reverse osmosis for water purification does not rely on chemicals that may be toxic when released in the environment. Reverse osmosis or RO water treatment systems work by passing water through a membrane that keeps contaminants on one side.
The down-side risk of high levels of reverse osmosis use in a property served by a septic tank and drainfield is that the system might be releasing an un-wanted quantity of additional water into the drainfield.
Reverse osmosis or R.O. water purifiers waste about four gallons of water for every gallon of purified water that they produce.
In normal use with a small point-of-use (POU) RO system (photo at left) such as one providing just a few gallons of purified water per day at a kitchen sink, the impact on a septic system is negligible.
But a large RO system may be a problem if the effluent absorbing capacity of the drainfield is limited.
Some designers or water treatment equipment providers such as Watts suggest routing the waste water produced by a reverse osmosis system back to the building plumbing system as gray water used for washing, bathing, or flushing toilets.
If you take this approach you can reduce the water waste from your R.O. system, possibly to zero.
If you plan to purchase a system that recycles wastewater from an RO water purifier, make sure that your system meets local plumbing codes - some systems, especially ones that do not further filter or treat the wastewater before it is recycled do not meet plumbing codes in some areas.
More information about Reverse Osmosis for water treatment and purification can be found at Reverse Osmosis.
Reverse Osmosis Systems - Impact on Septic Systems and Water Quantity Usage
What about water volume from reverse osmosis water treatment systems? These can
vary by manufacturer with a range of 3:1 to 10:1 of waste to product efficiency.
"Typically" for every gallon produced with a top of the line system, 3 to 5
gallons goes into the septic tank. Less efficient systems (regardless of
shutoffs) can dump up to 10 gallons to waste for every gallon that goes into the
storage tank. Don't despair...the membranes of ten years ago dumped up to twenty
five gallons per gallon of product.
Ask the manufacturer of your reverse osmosis water treatment system for their efficiency, platform statement,
and percent recovery data.
An excellent resource for membrane information is the
National Sanitation Foundation. We are not confident about the generalized
water quantity usage information obtained via EPA publications, Small Flows, etc.
If you ask reputable reverse osmosis treatment system manufacturers, you should be able to get
reliable water usage and water flow information. -- Larry Newcomb Encinitas Learning Center
[Thanks to Larry Newcomb Encinitas Learning Center, firstname.lastname@example.org, for the
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Watts Industries of North Andover, Mass., provides its ZRO-4 under counter system intended to target the independent water dealer market.
Ohio State University article on the concentration of chlorine necessary to act as an effective disinfectant, and the effects of the water's pH and temperature: See http://ohioline.osu.edu/b795/b795_7.html for details.
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: email@example.com
Thanks to Larry Newcomb Encinitas Learning Center, firstname.lastname@example.org, for the
above opinion concerning reverse osmosis treatment system water consumption rate
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.
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
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.
Carson, Dunlop & Associates Ltd., 120 Carlton Street Suite 407, Toronto ON M5A 4K2. Tel: (416) 964-9415 1-800-268-7070 Email: email@example.com. The firm provides professional home inspection services & home inspection education & publications. Alan Carson is a past president of ASHI, the American Society of Home Inspectors. Thanks to Alan Carson and Bob Dunlop, for permission for InspectAPedia to use text excerpts from The Home Reference Book & illustrations from The Illustrated Home. Carson Dunlop Associates' provides extensive home inspection education and report writing material.
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.
TECHNICAL REFERENCE GUIDE to manufacturer's model and serial number information for heating and cooling equipment, useful for determining the age of heating boilers, furnaces, water heaters is provided by Carson Dunlop, Associates, Toronto - Carson Dunlop Weldon & Associates Special Offer: Carson Dunlop Associates offers InspectAPedia readers in the U.S.A. a 5% discount on any number of copies of the Technical Reference Guide purchased as a single order. Just enter INSPECTATRG in the order payment page "Promo/Redemption" space.
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.
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 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