Avoid waterborne illness issues by assuring that your motorhome’s water supply is clean and free from harmful contaminants.
By Gary Bunzer
March 2013
When discussing the RV water system, I’m fond of quoting the ancient Greek poet Pindar, who stated, “Water is the best of all things.” Though Pindar, who lived circa 522-438 B.C. and predated our culture by just a few years, never could have imagined that his words would have import in today’s modern world of motorhome travel, they remain relevant. This is especially true for those who prefer to dry camp away from civilization and rely on the onboard supply of fresh water. One of my “RV Facts of Life” states that the fresh water in a motorhome’s water tank is only as fresh as the water source used to fill that tank.
In 1998, USA Today analyzed records from the nation’s 170,000 regulated water systems for the years 1993 to 1997 and concluded, “Each day, millions of Americans turn on their taps and get water that exceeds legal limits for dangerous contaminants. Millions more get water that isn’t treated or tested properly, so there’s no telling if it’s clean.” According to the Journal of Water and Health (04.Supplement 2, 2006), between 1920 and 2002 at least 1,870 cases of waterborne disease outbreaks occurred, an average of 22.5 instances per year. Between the years 1991 and 2002 alone, 433,947 water-related illnesses were reported.
The worst outbreak of a waterborne illness in recent U.S. history occurred in 1993 when a parasite in Milwaukee’s water system killed at least 50 people and made another 400,000 sick. A report by the Medical College of Wisconsin and the EPA estimated that 7.1 million Americans suffer nausea or diarrhea yearly because of foul water. Obviously, it is in our best interest that we take a proactive stance when filling the fresh-water container from any unsubstantiated public spigot.
I was raised out in the country in Florida where we lived on well water, and I joke in my seminars that you could smell that water two counties away. Readers familiar with sulfur water know what I’m talking about. It’s not so much the odor but other microbiological anomalies that we should be aware of, specifically viruses, parasites, and bacteria.
Waterborne bacteria and parasitic protozoa remain a serious concern, since the typical disinfecting processes adopted by municipal or regional waterworks facilities do not usually affect those types of contaminants. As in the case of the Milwaukee outbreak, the parasitic cyst cryptosporidium is common to virtually every surface water supply worldwide.
Cryptosporidium literally means “hidden spore or germ.” The tiny cryptosporidium parasite is only 3 to 7 percent the diameter of a human hair and causes severe flu-like symptoms. Unfortunately, when a person becomes infected by this parasite, in most instances it must be left to run its course, as there is no cure. Inside the victim, each parasite reproduces fourfold, so it’s understandable just how slow the recovery process might become. Obviously, it is best to avoid allowing it into the body in the first place, so it’s important to remain diligent regarding the water you store onboard or allow entry into the motorhome.
So, what can we do to protect the motorhome water system and ourselves? There are three basic options. One is to boil all water prior to use. Boiling definitely kills bacteria, viruses, and parasites, though this is not very practical for day-to-day RV living aboard a motorhome.
A second option is to use bottled water. Again, this is not very practical for motorhome owners. It also can also be expensive and inconvenient, and there is no guarantee that the bottled water is 100 percent pure. The National Resources Defense Council (www.nrdc.org/water/drinking/bw/exesum.asp) reported that one-third of more than 1,000 commercial bottles of water tested from 103 different brands “violated an enforceable state standard or exceeded microbiological-purity guidelines, or both.” In other words, about one-third of the bottled waters they tested contained significant levels of chemical or bacterial contamination.
The third and likely the most practical way to ensure that the water you are using is safe is to install and employ a point-of-use (POU) water filtration system. This option is the most viable, convenient, and readily available to all motorhome owners. Many companies have thrown their hat into the ring with an assortment of effective filtration and purification products. The best system for you, however, depends on your traveling habits and the cleanliness of the water source you are likely to tap into.
Many POU systems are installed under the galley sink. They are used to deliver fresh water directly to a single dedicated faucet for cooking and drinking. Another option is an in-line external unit that provides filtration of the water before it enters the motorhome and does not take up precious under-the-counter storage space. The benefit of such a system is that all incoming city water is processed, so you can enjoy showers without the heavy metals and odors sometimes found in campground systems. It’s wise to use a portable in-line purifier when filling the fresh-water tank on the motorhome. As water is processed through the filter just before it enters the city water inlet or the gravity fill of the fresh-water tank, submicron particles, bacteria, cysts, and unwanted chemicals are removed by the active filtering media, typically carbon.
So just how does activated carbon remove the contamination? It’s done through a process called adsorption. Adsorption is the physical progression that occurs when dissolved molecules, bacteria, and other particles are attracted to and attach to the surface of the adsorbent, in this case, carbon. Do not confuse the meaning of adsorption with the better-known process of absorption, which can be likened to a sponge soaking up water or how a typical RV absorption refrigerator uses heat to “make cold.”
As an adsorbent, especially when filtering trihalomethanes (THMs), volatile organic compounds (VOCs), pesticides, and fungicides, activated carbon is quite effective, because its surface area is quite large — approximately 1,000 square meters per gram. To put that into perspective, a piece of carbon the size of a single green pea can yield a surface area a little larger than the size of half a football field! But there is a downside to using carbon as the only filtering media. Exposure to chlorine — common in many water supplies — will quickly deteriorate the adsorbing qualities of carbon, rendering it minimized or useless after as few as 200 gallons of filtering. By the way, if you apply the approved method of chlorinating the fresh-water system using household bleach (see sidebar), be sure to remove or bypass the water purifier first.
Companies such as Hydro Life Inc. and General Ecology Inc. have improved upon the process of carbon-only filtration. General Ecology has developed a unique technology employing a “Structured Matrix” filtration component that instantly filters the water without the use of chemicals, double-treating, or other time delays.
A longtime exhibitor at FMCA Family Reunions, Hydro Life has perfected a filtering media that employs carbon along with the company’s patented KDF media. KDF causes an electrochemical reaction that neutralizes harmful chemicals and dangerous metals such as lead. As an example, chlorine is broken down into a harmless chloride after being zapped with the 0.04 volts produced when the water passes through the KDF. The water then flows through the carbon to complete the filtering process.
Another name synonymous with motorhome travel is SHURflo. Aside from the company’s popular line of water pumps, SHURflo also offers the Waterguard Water Filter Kit as well as the Everpure line of purifiers. The Everpure system utilizes a super-chlorination/dechlorination process to attack bacteria, viruses, cysts, rust, and other heavy metals, all of which can lead to foul-smelling, foul-tasting water.
Many other brands and types of purifiers and reverse-osmosis treatments are available in the RV aftermarket, too many to detail here. But the best thing you can do is to perform your own due diligence. Look for a filtration/purification system that satisfies or exceeds the recommendations of “Standard 53: Drinking Water Treatment Units – Health Effects” (www.nsf.org/business/drinking_water_treatment/standards.asp), as determined by the National Sanitation Foundation (NSF), a third-party certifying agency. If you are considering a reverse-osmosis system, refer to “Standard 58: Reverse Osmosis Drinking Water Treatment Systems.”
To ensure proper filtration efficiency, always replace the filtering media or cartridge at least once each year. Keep in mind, the longer a filtering media is in service, the less effective it becomes. At some point, an exhausted purifier may begin dumping contaminants back into the fresh-water system. Such a situation developed in Walkerton, Ontario, back in 2000 that resulted in 2,200 cases of gastrointestinal illness and seven deaths (www.nccph.ca/docs/SDWS_Water-borne_EN.pdf). In situations where heavily contaminated water is encountered, it may be necessary to replace the filtering media more often.
That, I’m guessing, is what Pindar would do if his traveling methods included a motorhome. Remember, RVing is more than a hobby; it’s a lifestyle!
Sanitizing And Chlorinating The Fresh-Water System
Not only could foul or stale-tasting water ruin an excursion, but it also may be harmful in some cases. If foul-tasting water persists, it may be necessary to chlorinate the entire fresh-water system.
In conjunction with water safety experts, Recreation Vehicle Industry Association (RVIA), the organization that oversees RV construction practices, has come up with the “official” method for chlorinating the fresh-water system and components. Following is the method taught to professional service technicians in all RVIA/RVDA-endorsed RV schools.
1. Drain and flush the fresh-water tank; leave empty.
2. Mix 1/4-cup of liquid household bleach (sodium hypochlorite) solution with one gallon of fresh water.
3. Pour directly into the fresh-water tank through the gravity fill. Note: If the motorhome is not equipped with a gravity fill for the fresh-water tank, use a funnel to pour each gallon of the mixture directly into the fresh-water hose prior to connecting it to the city water source. Some motorhomes may be equipped with an alternate method of pumping the chlorinated mixture directly into the fresh-water container.
4. Add one gallon of this chlorine/water solution for every 15 gallons of fresh-water tank capacity.
5. Top off the tank with fresh water.
6. Remove or bypass water purification equipment and/or filtering cartridges.
7. Turn on the water pump and open every faucet in the motorhome, including the exterior faucets and showerheads.
8. Allow the solution to pump through the system into the toilet, through the water heater, and to every hot and cold faucet at each sink until the distinct odor of the chlorine is present at every fixture.
9. If applicable, at the city water inlet, gently use the eraser end of a pencil to depress the check valve and briefly allow the solution to pump out the city water inlet until the chlorine odor is detected in the discharge.
10. Close all the faucets and turn off the water pump.
11. Allow the system to stand dormant for four hours. This will chlorinate and disinfect the system, including the fresh-water tank, the water heater, the faucets, the complete piping system, and all fittings to a residual level of 50 parts per million (ppm).
12. At four hours, drain and flush the system once again and top off the water tank with fresh water.
To avoid possible damage to delicate plumbing components found in some water pumps, do not allow the chlorinated solution to sit longer than four hours in the fresh-water system. If 100 ppm residual concentration is required or desired, use 1/2-cup of bleach instead of 1/4-cup with each gallon of the solution and let it stand for one to two hours.
If the odor of the chlorine is still too strong after performing the sanitizing procedure, drain, refill, and flush the tank until you are satisfied with the odor and taste, or lack thereof. This process should be performed after any extended period of nonuse, such as after storage, winterization, or whenever stale or distasteful water is experienced, but not less than once per camping season.