Simple Sewer Tips

July 29, 2010

If you have full hook-ups in your RV then you know black and gray water tanks are a fact of RV life, or you're about to. Yes, horror stories abound, but if you follow some basic tips for emptying and caring for your tanks hopefully you won't have a story to add to the campfire tales!

Basic Sewer Information

Black water tanks hold waste from your toilet. Gray water tanks hold waste from your sinks and showers. It's that simple. Black water tanks have far more solids obviously, and tend to have more problems if you don't use them correctly.

Tips for Emptying Your Tanks

• Always empty your black water tank first. The soapy discharge from the gray water tank will help clear the nastier, smellier residue from the hose.
• Don't dump your blackwater tank until it is at least two-thirds full.

Tips for Hassle Free Blackwater Tanks

• Never leave your blackwater tank valve open when you're hooked up to a campsite. The liquids will drain and leave the solids to harden on the bottom of your tank, as well as create a smell that will escape the tightest toilet gaskets. If you ever forget this rule and must figure out a way to get the solids off the bottom of your black water tank, try dumping 20 to 40 pounds of bagged ice into the toilet, adding water until the tank is half full, and a usual black water tank additive to the mix. Drive as usual for three to four hours. The ice will tend to knock the chunks of solids off of the sides and sensors inside the tank without puncturing or harming the tank as you might if you used a stick to try to remove it. The ice will eventually melt and can be drained out of the tank, taking with it any displaced solids. Depending on how serious the problem is you may have to repeat this step several times. Many owners do this as a matter of course once or twice a month or each time they move their RV from site to site to ensure all solids are removed from the walls and senor units before they harden.
• There are a lot of inexpensive, poly-vinyl hoses on the market. Don't be tempted to use them. They can rip or tear, leaving you with an awful mess to clean off of the dump hole station decking. Use a heavy-duty sewer hose at least 10 feet long and a 20-foot length if you can find one, to make the entire task easier.
• Many stations have a hose for rinsing off your sewer hose after dumping. Most do not. Carry your own spare and clearly label it. Many RV'ers use color-coded hoses - such as black for sewer hose rinsing and white for potable water supply hoses. Never store your sewer hose with your water hose. Better yet, use an extra large clear bag to store your water hose. If you think it has become contaminated or touched other hoses, don't hesitate to rinse it out thoroughly with water and chlorine bleach - either by submersing it in a clean bucket or by pouring water and bleach into the bag.
• Never, never, ever use your water hose for anything other than putting water into your potable water tanks. It's a good idea to turn on the water faucet where you hook up your water supply and let it run for a minute to flush out any dirt, insects or fungi that may be just inside the faucet head. Some people go as far as to add chlorine bleach to a cup or bucket of water and hold it so the faucet soaks in it for a minute to sanitize it before screwing on their water hose.
• Always wear protective rubber gloves and avoid touching the outside of the gloves. Dispose of disposable rubber gloves in the trash, not in the sewer dump hole.
• Wash your hands thoroughly with soap and water and use a sanitizing crème after dumping your tanks.

Dump Station Etiquette

• If other people are waiting to use the dump station, don't rinse your tanks or stop to add chemicals to the tank until you've pulled away from the station.
• Leave the dump station cleaner than you found it.
• Never put anything into the dump station but the contents of your holding tanks. Don't put anything in your holding tanks but human and bodily waste and toilet paper. No tampons (even disposable ones), no female sanitary napkins, no food, no cigarettes, no trash, no wrappers, nothing.

How to Properly Empty Your Holding Tanks

Use disposable rubber gloves and rubber boots. Once you're used to the process you may forgo the boots, but it's easier to rinse waste off rubber than off your cotton or leather footwear. If you do it right you shouldn't have any splashing, but just until you're used to it, why take chances.

Don't open any valves until your hoses are hooked up, in place and you're ready to empty the tank.

First remove the holding tank outlet cap. Using your three-inch sewer hose, connect it to the outlet of your blackwater holding tank. Extend the hose to the opening of the dump station. This is usually a hole in the ground slightly larger than the three-inch hose and sometimes well marked and sometimes not. (If you're not sure, park to the side and watch someone else empty their tanks while you observe.)

Insert your sewer hose into the dump station's hole at least four to six inches, further if your hose will reach that far. Use the hole's metal cover, a rock, or something heavy enough to hold the sewer hose in place so it doesn't come out of the hole. There are devices at some camping stores that will secure this for you as well, or you can have a partner simply hold the hose in place.

Once you're sure that both ends of the hose are securely connected and the exit end is held down, then open your black tank valve. You'll hear the a short rush of sewage flow out and down the hose and it may move or jump slightly - which is why you want the exit end secure! After a minute or so the fluid will slow down, then eventually stop. When it does, close the black tank valve. Make sure the exit end is still securely in place in the dump station hole. Sometimes it will move up and barely be in the hole - usually just enough for the next rush of gray water to kick it out. So check carefully unless you don't want to spend the next 15 minutes washing down the deck around the hole where your gray water spilled.

Now open the gray tank valve. Again, you'll hear the same thing - water flow, slow, and stop. Close the gray tank valve.

You're almost done. If no one else is waiting to use the station then you can fill your tanks and run a rinse of water through them and repeat the process to ensure the tanks are clean - particularly if you will be hitting the road again. There are devices, from a tank wand to a reverse flush valve called "The Flush King." It connects directly to your sewer outlet and rinses and cleans both holding tanks in one simple operation. A see-through through barrel lets you watch the water so you know when the tanks are really clean. If other RV'ers are waiting to use the station, skip this step, or go back to the end of the line. Over time grease and other residues will build up in your tanks even if you drain them properly every time. So, periodically treat the tank with the proper chemicals to break that down, or wash them out with dish-washing detergent to dissolve the grease. Rinse thoroughly.

Finally, double check both your gray and black water tanks to make sure they're securely closed. Disconnect the sewer hose at the RV and lift it up as far as you can as you walk it towards the dump hole. This will help drain any residual waste in the hose.

With the end of the hose still in the hole, use a non-potable water hose (not the hose you use to fill your drinking water tank!) to run water through the sewer hose to rinse it out. Some stations will have this hose there, some will not. Remove the sewer hose from the dump station hole. Rinse off the outside of the hose and the area around the hole to ensure you've cleaned up any possible spillage. Cover the hole; secure your sewer hose and your non-potable hose. Rinse your gloved hands off, then carefully remove the gloves and dispose of them in the trash, not in the dump station hole!

Drive off so others can use the station, then pull off and put about five gallons of water or enough to cover the bottom of your tank, into the black water tank. Add the appropriate amount of holding tank treatment, usually about four ounces for every forty gallons your tank holds. Do the same with your gray tank.

Now you're done!