The Holy Grail Portable Grey Water Tank Solution!

The Holy Grail Portable Grey Water Tank Solution!
After taking your small travel trailer on a number of trips, you get a feel for the types of places where you like to spend time.  For most people, these locations include State and National parks and many of these campgrounds do not offer Dump stations.  For the first year with our Scamp 13’, it was necessary to plan our adventures so that stays at such places were limited to only several days because that’s the time it usually takes for our twenty one gallon Grey tank to become full.  Our Grey tank was our limiting factor (not the Fresh, nor the Black tank).  Of course, we could elect not to take hot showers every night (brief ones!), but what fun would that be?!!!  It’s nice to feel fresh and clean before going to bed each night!

We learned through experience that the Grey tank is a small travel trailer’s Achilles heel when hookups aren’t available.  For us two people (taking 2 showers each night), our twenty one gallon Grey tank fills up in about three days.  Once the Grey tank is full, water can no longer drain from the shower floor or sink, and water backing up into these areas is highly likely.  The Fresh water tank is much easier to manage because the 12 gallon tank can easily be refilled using a portable water jug and water is usually available at most campgrounds (but not all).  Additionally, water can be stored in portable containers and transported in the tow vehicle.  We’ve found that the 9 gallon Black tank takes much longer to fill than the Grey tank.  Our Black tank usually takes about 6 days (two people) before needing to be dumped.  Lastly, although technically not a tank, we consider our 12V battery to be like a tank as it holds our electrons (about 12.6V when full).  These electrons are vital in keeping our Scamp running (e.g. LED lights, water pumps, furnace pump, fan, etc.).  When our battery is not hooked up, it can drain pretty quickly (within a couple days) if not carefully monitored.  However, we use our solar briefcase and it does a great job of keeping the battery topped off (as long as there’s sun every couple of days).  Our Jackery 500 also helps us keep our Scamp battery reserved for necessary functions.

Our travel strategy thus far has been to carefully arrange stops so that the ones without a Dump are limited to only a few days maximum (or have a Dump station available at a convenient service station).  For example, on our trip to Lake Tahoe last July, we first stopped in Santa Barbara and driveway-camped at our cousin Jon’s house.  Since our next stop was going to be at an olive oil farm in Paso Robles without hookups followed by street camping at my sister’s house in Oakland, we dumped at a 76 station on the way out of Santa Barbara.  We didn’t want to risk having a full Grey tank and not being able to use any water in our Scamp.  We knew we could dump at DL Bliss State Park at Lake Tahoe after our Oakland stay over, so we would be OK as long as we did this interim Dump.  The following month, we took a trip to Observatory Campground (Palomar Mountain) to view the stars.  There are no hookups here (although water spigots are available), so again we needed to carefully consider our time up on Palomar Mountain to ensure our Grey tank was not filled up (we ended up staying only one night).

The trip that really got us thinking about a way to extend our boondocking stays was Mammoth Lakes last August.  Our friends Hugh and Cheryl stay at Silver Lake Resort the same week every year.  They invited us to join them last summer and we were lucky enough to get a reservation.  This private RV park is right on Silver Lake (close to Mammoth Lakes) and is very popular and hard to get reservations at.  The spaces are tight (huge RV motorhomes very close to each other) and pricey (around $49 / night), but provide a great location and scenic views with a mountain backdrop.  Additionally, there are full hookups, a general store, and a nice restaurant (as well as boating and fishing on the lake, horseback riding, and great hiking trails).  We enjoyed our stay there, but couldn’t help but notice a large State campground called Silver Lake Campground right across the street and directly on the lake!  We walked the campground and were impressed with the very wide and private campsites and beautiful lake and mountain views (and a bargain at only $27/night!).  There are water spigots here, but no Dump station.  We knew we really wanted to stay here the following summer, but needed to figure out a way to extend our Grey tank limitation.  We were told the closest public dump station to this area is more than 20 minute’s drive away.

We considered an outdoor shower since our Grey tank is mostly filled by shower water, but ruled that out because of a few reasons.  An outdoor shower is technically considered Grey water dumping and, in turn, may not be permitted (depending on the campground and judgment of the camp host).  If an outdoor shower is permitted, it is likely that all the runoff water generated will need to be contained and disposed of properly (which could be a challenge).  And, there are potential privacy and safety issues since the shower is outside with no security.  Lastly, depending on the weather and environment, the outdoor shower may not be very comfortable.  With all the potential issues of an outdoor shower, we decided it wasn’t a good solution to our Grey water limitation.

A friend of mine showed me his 38 gallon portable grey water tank on wheels that he takes on his RV trips.  With water weighing roughly 8.3 lbs. per gallon, this portable tank can weigh over 315 lbs.!!!  He says it’s nearly impossible to move by bike when full, so he only takes it on trips when he knows he can move it with his vehicle to Dump.  We then looked at smaller portable storage tanks because they are more manageable.  Specifically, the Barker 5 Gallon Tote seemed to be a good option.  It’s only 5 gallons, so weight when full doesn’t exceed much more than 40 lbs.  It’s also small and can be easily transferred by a dolly or car to a Dump station.  The thing I didn’t like about it is that is a bit pricey (almost $50 per tank) and I would need 4 of them to give me the desired 20 gallons storage (so we could almost double our current 21 gallon Grey tank capacity).  Additionally, it isn’t transparent, and I wanted to be able to see the tank filling up so I know when it’s time to close the Grey water dump valve to ready the next tank for filling.

After a lot of thought and searching, I found what I believe is the Holy Grail of Portable Grey Water Tank solutions!  It’s actually a combination of individual items where the whole makes up more than the sum of its parts!  The first critical item to the system is the 5 gallon tank.  I found a perfect one online at Uline that is designed for chemical storage (so it’s beefy) and is also translucent (so the Grey water is visible in the tank as its being filled).  At the time of this writing, if you buy 3 jugs or more they are only $10.90 each!!!  Uline also sells separately a replacement top ($2.10) that has a threaded opening which allows a garden hose to be attached —  a hole just needs to be drilled in it for water to pass.  The next necessary component is a bayonet adapter so they the garden hose may attach directly to the Grey tank on the trailer.  Lastly, a small garden hose (like this one) makes the entire kit small and very transportable.  So, for about $60 in parts, this entire 20 gallon system can easily be assembled and put together with little effort (just a single hole needs to be drilled in the replacement cap used for attaching the garden hose to the 5 gallon tank).

Everything seemed perfect on paper, but until we tested the system, we didn’t really know if we had found the Holy Grail of Portable Grey Water Tanks.  An 8-night trip from our home in Carlsbad, California to Pinnacles National Park in California’s Central Valley and then down the coast to Big Sur, Pismo Beach and Santa Barbara provided the perfect proving grounds for this new and untested portable Grey Water Tank holding system.  Although Pinnacles National Park has a central Dump station, it is far away from Site #69 (the site where we spent a couple of nights).  This was a good opportunity for our first test.  When the Grey water tank was about 50% full on the 2^nd day, I hooked up the system.  Note:  I leave both the Valterra cap and water jug cap attached to the short hose, so it’s just a matter of attaching the Valterra cap end to the Scamp’s Grey water pipe (remove existing cover) and the jug cap to the water jug.  After both ends are attached, the Grey water tank valve is opened to release the Grey water.  On the first attempt, the water flowed quickly for a few seconds and then stopped.  I couldn’t open the small air release cap on the jug because it is on the opposite side (close to the ground) to the main jug cap and water would pour out.  The secret is to slightly open the main cap just enough to release air pressure (I could hear a slight breath of air when I did this).  This method works and air pressure is released while water does not escape. The jug fills up fairly quickly.  When it looks like the jug is almost full with water near the top, close the Grey water valve on the trailer, unscrew the cap on the jug, and then screw the cap onto the next empty jug (and repeat until all 4 jugs are full).  Cap the full jugs using the supplied standard cap so no grey water leaks while transporting the jugs to the Dump.  To dump these jugs, just open the main cap and also remove the air release cap, and then pour the Grey water directly into the open Dump hole.  The water comes out quickly and easily.

We had a chance to test the system again at Pfeiffer Big Sur State Park.  Similar to Pinnacles National Park, Pfeiffer Big Sur SP Campground has a central Dump station, but it was far away from the site we stayed at.  It would have been very inconvenient to have to tow the Scamp to the central Dump in the middle of our 3-night stay.  Instead, we put the Holy Grail system to use and it performed wonderfully (just like it did at Pinnacles).  This enabled us to stay set up and Dump at the central Dump on the way out of the park.  The 5 gallon jugs were very manageable for me to lift and pour into the open Dump hole and the 4 containers fit in our SUV tow vehicle really well.

In conclusion, this system does appear to be the Holy Grail Portable Grey Water Tank Solution!  It is highly portable (limiting jug weight to around 40 lbs.) / not too big, relatively inexpensive, simple to set up, jugs are transparent, easy to use, and works really well.  For a trailer like the Scamp, four 5 gallon jugs will almost double the off grid capability of the Grey tank.  And, it certainly is nice not having to limit campground visits to only 2 – 3 days due to Grey water tank size.  For the Scamp’s 21 gallon Grey tank, this system effectively doubles time between dumps from 2 – 3 days to 4 – 6 days (depending on water use).  And, it’s also really great not having to pack everything up and drive to a central Dump in the middle of a trip and then have to drive back to the campsite to set up the trailer all over again (which we had to do in the middle of a 3-night stay at D.L. Bliss State Park at Lake Tahoe).  We have a three night trip to Joshua Tree National Park next month and now we can rest easy knowing we will not have to break camp or stop using water for the time we are at the park!  Finding the Holy Grail is life-changing and you will be transformed too if you set up this system!

Disclaimer:  You will get the same great Amazon price by clicking on the links here compared to buying directly on Amazon, but by buying here you will also be supporting the continuation of this website as we get a small commission from each sale.  These are products and procedures we use for our own Scamp that we selected and developed from our own research and experiences.  However, we do not endorse any specific product and cannot guarantee that the products we use are exemplary and the procedures we use are complete, accurate, detail the correct recommended procedures, or apply to your model small travel trailer.  It’s always best to double check with your manufacturer or operation manuals to ensure you are doing everything correctly.