By Bob Difley
Most of us boondockers are able to stock enough peanut butter, fruit of the vine, double-A batteries, and the other essentials allowing us to spend great blocks of time in the hinterlands well beyond shouting distance from the nearest hookups. But we are still limited, unfortunately, by depleted fresh water stores and full waste tanks.
But I recently talked with Greg Corwin (USI-RV), who has developed a couple of systems that will greatly extend the number of days we can boondock or dry camp before having to stow our stuff and head to the dump and water fill station. Following is my interview with him on how these systems work:
BOB: Your system of recycling gray water to flush the toilet is fascinating, since filling the gray water tank is often the time limiting factor in dry-camping and boondocking.
GREG: The approach takes your gray water (typically shower and sink water), filters it, pressurizes it, then uses it to flush your toilet thereby saving fresh water and removing water from your gray tank. The end result is each toilet flush empties your gray tank a little leaving more space for showers. Our system has special valves that provide fresh water to the toilet when no grey water exists, like right after you dump at a dump station.
BOB: I can see how that would be a big advantage to dry-campers trying to extend their stay as long as possible. But what about the filter, how often does it have to be changed or cleaned?
GREG: After extensive field trials we standardized on carbon wrap filters which you can buy everywhere for less than $5. They provide the best filtration while maintaining flow rate. A filter will typically last for two to three weeks with normal facilities usage. I personally have gone as long as a month of continuous use between filter changes. The key is to keep using your toilet daily. This keeps gray water flushing through the filter which keeps the soap residue from thickening. The system is designed so you can change the filter without emptying your gray tank and without getting your hands wet. This allows field changes in the event your water pressure at the toilet becomes less then optimal. Note: I have gone as long as 4 months with less frequent use although I used the kits filter flush feature between trips. As with all conservation activities there are some minor trade offs to maximize your benefits. There are two items you need to watch with gray water recycling; protein items (food particles) going into the gray tank and shampoos/soaps with conditioners in them. With some simple modifications to your habits, you can have gray water recycling extend your Dry Camp Days (DCD = days without water hook up facilities) by almost double. Some customers have experienced an increase of more than double, it’s all based on your tank sizes. Often, folks are concerned about the potential odor from gray water. This is mostly tamed by not putting protein based items (food particles, etc) into the gray tank. If odor is still a concern simply pre-treat the gray water with a gray water tank sanitizer (one that has enzymes to breakdown the grease).
BOB: Does your parts kit include everything—including good directions–an RVer would need to plumb the gray tank to recycle?
GREG: Yes, our kits include everything you need (except the extra water pump) including extra straight and 90 degree plumbing parts because you never know what you’re going to need. Our philosophy is to eliminate the customers from needing to go to the hardware/plumbing store. Our installation instructions are laid out in a format that provides background information then step-by-step guidance, with illustrations, through the install process. Lots of how-to tips and tricks are included as well.
BOB: Where can RVers buy this installation kit and how much does it cost?
GREG: The kits and other products are available from our USI-RV website. The Gray Water Recycle kit costs range from the mid $200’s to low $300’s depending on options you select. The pricing is based on major hardware store (i.e. Home Depot, ACE, etc) prices for the parts.
BOB: You also have a hot water recycling kit, which I assume works in the same manner.
GREG: Similar yet different. This product takes a tap off your hot water line at any faucet (typically the shower) and through a timer controlled valve allows the fresh hot water line to circulate back into your fresh water tank. It’s a closed loop system so no bacteria can enter and after about 20 seconds of circulation operation, you have instantly hot water at your faucet or shower. You don’t waste even a drop of fresh water or gray tank storage space warming your water. No additional pumps, tanks, or hot water heaters are needed.
BOB: Are both the gray water and hot water circulation kits easy enough to install that the RVer with average handy man skills could install it and how long should it take?
GREG: The kits are designed for average Do-It-Yourself (DIY) type skills and tools. We recommend you read the installation instructions starting at the beginning and follow the steps in the order presented (check off each step as you proceed). This will ensure the install goes smooth and quickly. We have received many complements from customers on the completeness and ease of use for our installation instructions. The install time varies with the product being installed. The bulkhead Blind Tank Fitting averages 5-10 minutes and the Insta Hot water Circulator product averages 45-60 minutes to install. The Grey water recycling product(s) take upwards of 4 hours. For professional installers we recommend about half the installation time.
BOB: I see that you also offer a Gray Water Recycling Calculator. Tell me about it.
GREG: This product runs in Microsoft Excel and provides the ability to enter your RV tank capacities, water usage habits, number of people living in the RV, etc. then calculates your Dry Camp Days (DCD). It also shows how your Dry Camp Days increases with Grey Water Recycling. Then the analysis engine gives you real time tips on how to increase your Dry Camp Days by suggesting changes to your water consumption habits. These are not generic suggestions, they are calculated based on your tank capacities and water usage parameters. It’s a great tool (even if you don’t use Grey Water Recycling) to know what your limiting factors are when dry camping. I use it to calculate the number of minutes the kids have per shower when boondocking so they don’t over use the limited resources for the number of days we are camping.
BOB: I assume you use both the gray and hot water kits in your RV. Have you been able to determine how long these installations have been able to extend your dry-camping days?
GREG: For me what you want to maximize depends on the number of days you are planning to dry camp. If it’s only a week long conference then I use the calculator along with the number of occupants to determine how long our showers can be. In this case, making the 6-7 days of a conference with daily showers is easy. So I want to maximize my daily shower time. When I’m going to be dry camping longer, then it’s about knowing how often I can wash dishes, how short my showers need to be, etc. to reach the desired number of days. So I use the calculator prior to most trips to determine what my constraints will be. The good news is I have never been surprised by needing to break camp early or calling a honey wagon for my tanks. Back to your question, the longest I have gone is just shy of a month which included taking daily showers. Another example would be one of the FMCA rally’s where I was on-site for 8 days with three adults taking daily showers. We left with plenty of fresh water and black/gray tanks were only at ¾ full so we ended up driving 2-days home before needing to dump the tanks. My tank sizes are 50/50 blk/gry and 90 fresh.
BOB: Is there anything else you would like to add?
GREG: We also have a book for sale on our web site. It’s a soft bound book that provides you all the information you need for understanding and implementing gray water recycling in your RV including diagrams, parts lists, installation steps, etc. This is great for the person that wants to come up-to-speed quickly on the subject and/or the person that wants to build and install their own kit. For additional information or questions regarding Unique Solutions Inc – RV Products, you can email us at info@USI-RV.com or check out our web site.
BOB: Thanks, Greg, for your time and for this information. It should enable us boondockers to greatly extend our camping days. How neat is that?
Take a look at my Healthy RV Lifestyle website and check out my ebooks: BOONDOCKING: Finding the Perfect Campsite on America’s Public Lands, 111Ways to get the Biggest Bang for your RV Lifestyle Buck, and Snowbird Guide to Boondocking in the Southwestern Deserts, all of which are loaded with information and links that you can use. You can download all or one immediately to your computer.