In Texas, a number of State Parks only have water and electric sites. On weekends, during busy times of the year, there is often a steady stream of RVers making their daily dump station pilgrimage. On Sundays (or Mondays on three-day weekends), it isn’t uncommon to wait in line to dump tanks while other RVers dump their tanks on the way out of the park.
There are two ways to get waste water to the dump station.
- Move the RV to the dump station and back
- Dump RV waste water into portable waste tank and take that back and forth to the dump station
Moving the RV back and forth to the dump station requires that the RV be “somewhat” travel ready: awnings in, slides in, breakables stowed, electricity disconnected and water disconnected. Trailers will, of course, need to be hitched. After returning from the dump station, the reverse needs to be done.
With portable RV waste tanks the process is simpler. Position the portable RV waste tank near the RV. Connect hose from RV waste outlet to portable tank. Drain RV waste into portable tank. Tow, carry, pull or drag the portable tank to the dump station and dump it.
Black and Grey Water
Black water comes from toilettes and is primarily composed of human waste (poop and pee) mixed with toilette paper. Grey water comes from showers, sinks, dishwashers and clothes washing machines.
Some people find using their portable RV waste tank for black water offensive. They may even believe that no amount of cleaning can remove the horror of the tank having ever been used for raw sewage. It is important for couples to have discussions and an understanding on using portable tanks with respect to which waste will be carried.
There are a number of design concepts at play in the different portable RV waste tanks. In addition to the tank, there can be:
- RV waste outlet coupler (bayonet fitting)
- RV waste hose with coupler (bayonet fitting)
- Gate valve
- Standard garden hose fitting
- Back wheels and tires
- Front wheels and tires
- Hinged handle (like a wagon handle)
- Built-in handle
The drawing below shows different features in different configurations built around the waste water tank.
The drawing below shows different ways to get the tank from the campsite to the dump station.
The wheels are often made from plastic. Sometimes the tires are hard rubber, sometimes plastic. Most portable tanks have rear wheels.
Some portable tanks have front wheels.
Barker offers a tire/wheel upgrade package that includes tires that might be used on hand trucks. This is one option for more robust wheels.
Yet none of the portable waste tanks that I have ever seen in use have been made to be towed at 30 MPH. Still, from time to time, campers will tow their tanks at high speeds.
Dump Station Distance
Campsite to dump station distances vary by park and campground. For example, at Seminole Canyon State Park in Texas, some campsites are within 100 yards of the dump station. In Big Bend National Park, the Cottonwood Campground is 57 miles to Rio Grande Village Campground in the National Park. The Chisos Basin Campground is 30 miles. At these distances, towing behind the car at walking speeds is near impossible.
Few people pull, drag or carry full portable waste water tanks to the dump station. Most people attach the tanks to their ball hitch and tow them.
The handles generally support hitching/towing.
The simplest method to avoid overflows is to have a larger portable waste tank than the tank being dumped. Given that the portable tank sizes don’t go past 40 gallons and many RVs have much larger tanks, this may not be practical for some campers.Barker provides Barker Manufacturing Company 26835 Tote-Along Bobber Gauge Full Tank Indicator, an floating indicator that pushes up outside the tank as the water level rises to the top. While a bit sluggish to respond at times, this simple solution works well for those willing to stand there and watch as the tank fills.
Thetford has a valve in the garden hose fitting that blocks air from escaping the tank when the tank fills up. Blocking the air from escaping also blocks more waste water from entering the tank. The challenge here is the fluid in the pipe between the gate valve on the RV and the RV’s waste outlet coupler. If more fluid can’t flow into the tank, decoupling the tank from the RV will spill that excess waste water on the ground and possibly on the person dumping the tanks. Yuck.
Just dump early and often to avoid trouble. Pay attention and learn the portable tank and RV tanks to understand what can be done before too much experimentation.
Filling Portable Tanks
Big hose or small hose? Many tanks have at least one standard RV female sewer bayonet connector and one standard male garden hose connector.
These connectors are used to connect to the RV’s sewer connection.
An alternative use, common with popup trailers, is to use a garden hose from the waste water outlet to the tank. In this particular case, an RV sewer to garden hose adapter would be used. Please note that a female to female hose adapter would also be needed to complete the hose connection to the garden hose threaded vent on the tank’s top.
Do not use potable (drinking) water hoses for for this use. Only use potable water hoses for potable water. Never mix and match potable with non-potable hoses.
Portable Tank Dumping
The ease of dumping portable tanks depends on individual dump stations. The following dump station layout/design is common in public parks.
Where the waste is dumped can be raised above road level requiring the portable tank to be pulled or lifted up a curb. Sometimes the curbs are 6 inches or more. Once the tank is in position, dumping is generally straight forward. Don’t fall into the drainage area. Don’t forget to block the drain open using large rocks or one of the standard sewer hose elbow connectors.
One common problem is getting all the water out of the tanks. Most tanks leave some residual waste water in the tank. One way to get this residual water out is to rock the tank so that the water sloshes into the tanks drain.
Leaving excess waste water in these tanks just makes them smell. In desert areas, leaving the cap off the garden hose connector is enough to allow the tank to dry out.
Bringing Tanks on Trips
Portable tanks are bulky – big and somewhat heavy. Finding a spot for them can be a bit tricky and will depend on the RV setup. Some of the places where portable waste water tanks can be stowed for transport are:
- Hung on RV ladder
- On luggage rack on top of RV, tow vehicle, tag-along vehicle or towed (toad) vehicle
- In RV storage compartment
- In towed or towing truck bed
- Inside truck, SUV, van, car, car trunk.
Storing Tanks When Not In Use
Tanks are made from plastic. Most plastics degrade in sun. In areas where it freezes, tanks should be completely emptied. Tanks have value and may be subject to theft. Common places to store tanks are: Storage sheds, barns, garages, RV basements and storage facilities. Note that the garden hose fixture is left open so the tank can air out.
Before we bought our first RV (25 foot fifth-wheel), we spent a year of weekends visiting the Camping World in New Braunfels, Texas. We looked at their new and used RVs and we looked in their store to see all of the wonderful products made to enhance the RV lifestyle. We saw portable RV waste tanks at Camping World but didn’t really understand their purpose.
Then in 2002, we branched out to campgrounds that didn’t have sewer connections. We conserved water by avoiding meals requiring washing dishes, showering in yucky park showers and limiting our stays to two nights or less. The self imposed limitations were worth it since most of the cool parks near our home didn’t have sewer. It is also worth noting that I wasn’t very good at parking the fifth-wheel in back-in campsites. The possibility of having to park the fifth-wheel multiple times per trip encouraged me to rigidly conserve grey water waste tank space.
That same year, we saw someone use a portable RV waste tank and immediately saw the potential. Since, we had seen the portable tanks at Camping World, we bought one there – Barker 27844 4-Wheeler Tote Tank – 32 Gallon Capacity. (This tank had a handle that fits over a tow ball to be towed behind a vehicle.) After that, we could stay in state and national parks without sewer hookups for the five days – the amount of time our black tank would last.
It was during this time Linda and I began to have discussions about whether or not we would use the portable waste tank for grey and black water or just grey water. No real discussion as far as Linda was concerned. No black water in the portable waste tank ever period.
A few years later, while camping at state parks in the Texas Panhandle, we ran across situations where the dump stations were miles from the campgrounds. Towing a portable waste water tank 5 miles at 5 MPH takes an hour. We thought that driving faster would cause the cheesy plastic wheels to break off and ruin the tank. Suddenly, we wanted the ability to put the 32 gallon portable waste tank in the bed of the truck. I remember from High School that water weighs around 8.3 pounds per gallon. The water alone would weigh around 266 pounds. More than normal people can lift.
Then I read about this new thing that combined a macerator with an waste outlet coupler to come up with the Flojet 18555-000A, Portable RV Waste Pump, 12 Volt DC, Macerator, Includes Carrying Case. Waste water comes in through the coupler, is chopped up in the macerator and is sent out a standard hose outlet under pressure. This poo-pump worked well to move waster water from our fifth-wheel tanks to the portable tank in the pickup bed.
In 2010, we sold our fifth-wheel. Later that year we traded our truck in for a car we expected could tow a 5,000 pound trailer. We were wrong about the car’s towing capacity and could never find a travel trailer under 3,000 pounds that we liked for towing. We gave away our Barker portable RV tank and the Flojet waste pump.
In 2012, we found a motorhome we liked. We outfitted our 32 foot Winnebago Aspect with a new portable waste tank. This tank (a Thetford SmartTote Portable Waste Tank with 4 Wheels and handle – 32 Gallon Capacity ), instead of having a round metal handle like the Barker that hurt my hands to pull when full, it has a wide plastic handle with a good grip. Both the old Barker and the newer Thetford can be towed by hand or by a ball hitch on a vehicle.
Thetford has replaced our portable waste tank model with the Thetford SmartTote2 product line. I have no opinion or experience with Thetford’s newer designs.
In 2017 we sold our motorhome and bought a truck and truck camper. We still use our Thetford SmartTote. Our truck camper grey tank (20 gallons) has considerably less capacity than our Thetford SmartTote. We are currently considering finding a smaller portable waste tank to use in the future. Regardless, we will keep the larger 32 gallon tank for when we have a fifth-wheel again.
We stow the Thetford SmartTote in our towed (toad) vehicle, a two door Jeep Wranger Rubicon in the space behind the front seat where the back seat would normally go. We removed the backseat from the Jeep just after we bought it because it just isn’t useful at our age and removing it gave us all kinds of space for cargo. With the back seat in, we couldn’t really use the back area to bring home groceries.
Hope to see you on the road ahead.