RV Plumbing, Water, and Sewer

There are two ways to add fresh water to your RV:

1) A direct connection to a water tap at an RV park or other location. This is called being on 'city water.' When you are connected to a water tap in this way, you have an unlimited supply of water at your disposal. Your only limit is your grey holding tank capacity unless you are hooked up to sewer and can leave the valve open.

2) Your fresh water intake, which leads to your fresh water holding tank. The tank in larger units can hold up to four hundred litres, but the smaller RVs usually do not have more than one hundred twenty or one hundred fifty litres. This tank is filled from potable water taps at RV parks, dump sites, gas stations, friends' homes, etc. Connected to these tanks is a 12 volt electric pump to pressurize the plumbing in the RV when it is not hooked up to city water. The pump does use a lot of battery power to run, but it is usually for such a short period of time that it will not run down your battery.

Water should be conserved when running off the holding tank, as the supply can be depleted very quickly. Some RVers are water conservation experts and can spend five days to a full week on five hundred litres, and that includes showering.

It is a good idea to turn off the water pump when leaving the RV or traveling to a new location since you could lose your fresh water if you spring a leak in your plumbing system, or even burn out the pump motor.

Only use a white potable water hose should be used to connect the RV to a potable water source. This type of hose does not leach chemicals or taste into your water supply.

First, attach your pressure regulator to the tap, and then connect the female end of the hose to the regulator. Turn the tap to rinse out the hose and fill it with water to remove as much air as possible. Turn off the tap, taking care not to lose too much water, and connect it to the fresh water fitting on the RV if staying hooked up to city water or to the fresh water intake if filling the fresh water holding tank.

Once the hose is connected to the RV, turn on the tap. Go inside to make sure all the taps are working. Open them slowly to let any remaining trapped air escape. Then, go back outside to check for leaks. Carry a roll of teflon to wrap around fittings as well as some spare washers. Moreover, sometimes the way to fix a leak is to loosen, not tighten, the fittings.

In some RVs, the fresh water holding tank intake requires the hose to be screwed in. This can be a problem at dump stations since often times their hoses do not have a male hose fitting at the end. To circumvent this, carry an adaptor that looks like a male hose fitting with a narrow rubber funnel attached to it, commonly called a 'water thief.' Hold the funnel end tightly against the hose to cut down on leaks. You may get a little wet!

As a reminder, fresh water is very heavy! Unless you spend most of your traveling time dry camping, it is better to travel with just enough water to wash up and flush the toilet.

It's hard to find a good RV fresh water hose with fittings that won't give out over time. There are online sources for heavy duty ones with brass fittings, but with me being in Canada, shipping costs are prohibitive. So, I've discovered that a good way to make a cheap hose last longer is to replace the standard fitting with a brass one.

Project cost: $4-6 depending on prices at your local hardware store

Difficulty: super easy

Materials:

one water hose with substandard fittings

one 1/2" female to male brass adapter

one 3/4" pressure fitting (you might be able to find a kit that has both the adapter and the fitting together)

a sharp knife

a flat head screw driver

teflon tape.

Simply cut off the original fitting from the fresh water hose. Slip on the pressure fitting. Twist in the brass adapter. Tighten the pressure fitting. Wrap teflon tape around the male adapter on your water pressure regulator (or the threads on the water outlet if you're foolish enough to not use a pressure regulator). Screw on the water hose. Turn on the water and check for leaks. Adjust the tightness of the pressure fitting (sometimes you need to loosen, not tighten, to fix leaks).

Total time: five minutes, not counting running to the hardware store and back.

For more pictures, check out my blog post Fresh Water Hose Repair/Upgrade.

The RV sewer system is composed of black and grey water holding tanks. Black water comes from the toilet and grey from the shower and the sinks.

Hooking up to an RV Park Sewer or Septic System

The sewer system is the last thing that should be hooked up to prevent the transmission of E coli bacteria to other components. It's a good idea to use waterproof gloves.

Larger RVs have sewer connections located in a compartment while the smaller units, including most class Cs, have external connections.

Connect the sewer hose to the park outlet; it may screw in or need to be weighed down. Next, ensure that the holding tank valves are closed, and then remove the cap while holding the RV end of the sewer hose underneath. Twist the cap to the left about one eight of a turn and slowly pull it off, starting at the bottom. This will make it possible to catch any sewage seepage. In rare cases, a valve might even be jammed. By holding the hose against the opening, it is possible to catch a potential mess. If there is a severe leak, it is easiest to hold onto the hose than to try to put the cap back on.

Connect the hose at the RV end and open the black valve while leaving the grey closed. Check for leaks, and then go inside once the flow of sewage stops. Fill the toilet with water and flush it a few times to flush out the leftover sludge that can be concentrated at the bottom of a holding tank. Some newer and larger RVs have a flush system that should be hooked up to its own hose.

Once the black tank is flushed and has some water at the bottom, the black valve should be closed and the grey valve opened. The grey valve can be left open as long as the RV is parked. However, it is a good idea for extended stays to occasionally close the valve to allow the tank to fill so that it can flush out any buildups within the tank.

The black tank valve should never be left open. This would cause the liquid to run out every time the toilet is used and solids to build up, resulting in what is known as a 'cone of death.' Such a situation can quickly lead to a need to have the holding tank professional pumped out, or, even require a replacement.

In an extended parking scenario, the sewer hose should always be installed on an incline to further encourage it to drain properly.

You'll need to dump your tanks at a dump station at some point in your travels. Not all RV parks have full hookups and a visit to a dump station will be necessary after a few weeks of dry camping.

Using a dump station is not difficult. It is only an issue when there is a lineup to use the station. In such a scenario, you need to be able to dump your tanks quickly and efficiently.

To speed up the process, have everything ready. If there are several people in the rig, the chores can be divvied up. For example, one person can take out the hoses and put them near the dump site while the RV is waiting in line. The partner can then guide the driver into position. Having to get back into the rig and move it a few times will only exasperate the people waiting in line.

Most RV dump stations have a metal lid that can be opened with the foot rather than a screw-in fitting. Connect as you would at an RV park. Since there is no place for the dump site end to screw in, it is a good idea to place a weight over the hose. Often, there is a brick or large stone available for this purpose. At some sites, the lid clamps down with sufficient pressure.

Do not go back into the rig to flush the black tank if someone is waiting in line behind you. Simply dump the grey after it immediately, and then remember to add water to the black tank before using the toilet.

If the dump station does not have a permanent cleaning hose installed, connect your wash down hose as your tanks are emptying. When the grey water tank is empty, close the valve and disconnect the sewer hose at the RV end. Hold it up and flush it with water while shaking it to rinse it all well. Wash away any spills around the area at the same time.

Then, move the RV out of the way and come back for your hoses. Many RVers never learn this etiquette and end up frustrating others.

Since there is rarely a place to wash up at a dump station, it is a good idea to have some latex or nitrile gloves in the wet bay. Often there is even a garbage can at the dumpsite in which to throw out the dirty gloves.

Many dump sites also have a potable water connection. Not everyone has the same hygiene standards; some connect to the fresh water after using the dump station without washing up first. It's therefore a good idea to keep a sanitizing spray at hand for cleaning the taps and hose connections before hooking up. Wipes are another solution.

Turn on the tap, rinse off the end of the hose or tap and connect to your RV either using the provided hose or your fresh water hose.

If there is a lineup, take only as much as you need and move on since fully filling a tank takes time. Moreover, traveling with a full tank increases the rig weight and reduces gas mileage.

RV dump stations all around North America can be found at SaniDumps. The site also offers information about dump station etiquette, RV holding tanks, and holding tank maintenance. Print copies, Know where to dump when your RV has to go... are also available for use when there is no internet connection.

A Blue Boy is a portable sewage tank on wheels with a handle, When it is not possible to hook up to a sewer system and driving every couple of weeks to the dump station is a hassle, you can use the Blue Boy to dump the grey and black holding tanks.

They have a fitting at the top to which a sewer hose is attached for filling and a gate valve at the bottom for emptying.

The problem with these carts is that they hold sixty or even eighty litres of waste and can weigh over one hundred fifty pounds when they are full. They then need to be lifted into the trunk of a car or the back of a pickup, sometimes with the use of ramp. Some people affix them to the ball hitch on the back of their vehicle or use a moped for towing, but this method is very hard on the Blue Boys.

A better way of dealing with the waste is to use a macerator pump. Put the Blue Boy in the trunk of the car or on the bed of the pick up, then pump the sewage into the cart. If using a pick up truck or SUV with a level bed, it's possible to drive to the dump station, hook up a sewer hose, and dump directly from the truck. With a car truck, it may be necessary to elevate the Blue Boy with blocks; this may mean keeping the trunk open during the drive. Use the macerator pump at the dump station by plugging it into the car's cigarette lighter. This will enable you to pump sewage over the lip of the trunk. When the Blue Boy is almost completely empty, it still needs to be lifted and tilted to ensure that everything comes out. Then, the unit can be flushed with clean water.

For more about Blue Boys, check out RV Portable Waste Tank.

The most common method for cleaning and maintaining the black water tank is to spray it from inside using a cleaning wand inserted into the tank with the black valve open. This method can get messy.

An alternative method is to empty the tanks when leaving an RV park then adding three or four toilets full of water and a liberal amount of biodegradable degreaser.

For the grey tank, add degreaser and hot tap water. Do this immediately before departure so that the hot soapy water has time to slosh around the tank while you are driving.

The movement of the rig as it is being driven will clean the tanks. In an ideal scenario, stop at a dump station and empty the grey tank while the water is still warm.

The cleaning mixture in the black tank can be left to help break down solids until the next time the tank is dumped.

There is much debate in the RVing community about whether or not chemicals are needed to maintain the holding tanks. The only consensus in this area is that any products used should be biodegradable and septic system safe. There are RV parks that have a septic system rather than being hooked up to a city sewer system. Many RV holding tank type chemicals are hard on septic tanks and may actually kill the beneficial bacteria in them that breaks down the sewage. A degreasing cleaner will not usually be a problem, but if in doubt, ask the owner of the RV park what the preferences are.

RV toilets are designed to operate with very little water, compared to the twenty litres needed to flush a standard toilet. They have a small amount of water sitting in the bowl to act as a seal and are operated with either foot or hand levers, one to add water to the bowl and the other to flush.

Waste from the RV toilet drops straight down into a holding tank. The best way to tell that the holding tanks needs to be emptied is that the toilet will belch as sewage creeps up into the vent pipe.

While there are many chemicals and special RV toilet paper available for maintaining the black tank all that is needed is a copious amount of water; on average, one half to one bowlful of water for wet waste and one to two bowlfuls for solid waste. This is still much less water than is used in a conventional toilet.

Before using your RV toilet after emptying the holding tank, add two bowlfuls of water to the tank to fill the outlet so that it does not get clogged with paper. Then, use the toilet while being frugal with paper and generous with water.