Some 60 percent of our household indoor water usage happens in the bathroom. Toilets are the biggest water hogs, with older models using as much as eight gallons per flush. A shower, even with a low-flow shower head, can use up to 40 gallons of water, and a bath can use up to 50-60 gallons. (Thinkstock)

Some 60 percent of our household indoor water usage happens in the bathroom. As such, updating old leaky fixtures and changing a few basic habits could go a long way to not only saving fresh water, an increasingly precious resource, but also money.

Undoubtedly, the toilet is the biggest water hog in the bathroom. Those made before 1993 use up to eight gallons of water per flush, five times what modern toilets use. “It’s a good idea to replace pre-1993 toilets if you can,” says Patty Kim of National Geographic’s Green Guide. (FYI, usually a toilet’s manufacture date is stamped under the lid if you want to check how old it is.) If it is older and you can’t or don’t want to upgrade it, Kim recommends rescuing a two liter soda bottle from the recycling bin and filling it partially with some water and sand or pebbles and then putting it into your toilet’s tank, where it will take up space and force your toilet to use less water every flush. Or get a Toilet Tank Bank for less than two bucks; it hangs in your toilet tank and displaces almost a gallon of water to save water on every flush.

Plumbing leaks account for some 14 percent of the total water usage in an average U.S. home. Toilets are often a major culprit. Kim recommends testing your toilet by putting 5-10 drops of food coloring into the tank, then put the lid back on but don’t flush. Check back in 15 minutes or so to see if any of the colored water leaked down into the bowl. If so, you have a water-wasting leak, and it might finally be time to replace that aging toilet after all. The EarthEasy website reports that replacing an older18 liter per flush toilet with an ultra-low volume (ULV) 6 liter flush model “represents a 70 percent saving in water flushed and will cut indoor water use by about 30 percent.”

The shower can also be problematic as a water-waster, especially if the shower head in question was made before new regulations went into effect in 1992 mandating lower flow. Kim says you can check to see if your shower head is older or not by turning the shower on full blast and catching its output for two minutes in a bucket. If the bucket is overflowing, then your shower head is an older, more wasteful model. Newer low flow shower heads won’t come anywhere near to filling the bucket after two minutes. A new shower head costs around $10 and is a great investment because you can save water and money with every ensuing shower. Regardless of whether or not you have a newer shower head, you can save more water by turning off the shower to soap up, then turning it back on to rinse. Eartheasy reminds us that even with a new shower head, even a moderately short shower can still use between 20 and 40 gallons of water. But that’s nothing compared to a bathtub, which can hold as much as 50-60 gallons of water.

Additional pearls of wisdom in regard to reducing bathroom water waste include turning off the faucet while brushing teeth. Better yet, fill up a glass with just enough water to rinse after brushing. Likewise for shaving, stop up the sink with a little warm water in it and wiggle your razor around in the basin between strokes. And if you suspect your faucet may be spraying harder than it needs to, unscrew the aerator tip where the water comes out and take it into a hardware store for a more stingy replacement.

CONTACTS: The Green Guide, http://environment.nationalgeographic.com/environment/green-guide/; EarthEasy, www.eartheasy.com.

Bedford-based iRobot has introduced its latest floor-cleaning device, one designed for cleaning icky bathroom floors and all those hard-to-reach places where grime collects.

The Scooba 230 is designed to be compact enough to clean tight spaces around toilets and alongside tubs. It’s 6 1/2 inches around and 3 1/2 inches tall.

It can also destroy up to 97 percent of common bacteria.

It will be available soon at $299.99. iRobot is also going to unveil another Roomba vacuum cleaner at the CES show in Las Vegas later this week.

Dear EarthTalk: I’ve heard that most of the big car rental companies have gone “green” lately. What’s the story? – Ari Zucker, New York, NY

No doubt, rental car companies large and small have responded to increased consumer demand for fuel efficiency in the last few years by stocking up on gasoline-electric hybrids and other vehicles with better mileage and lower emissions. But whether or not these companies will continue their commitment to fuel efficiency as gas prices fall and consumers begin to look again at bigger cars remains to be seen.

Hertz may have sparked the trend in 2006 when it launched its Green Collection, which includes thousands of fuel efficient cars such as the Toyota Camry, Ford Fusion, Buick LaCrosse and Hyundai Sonata. These models, now available at 50 airport rental locations, average 31 miles per gallon (mpg) on the highway, and most carry the U.S. Environmental Protection Agency’s (EPA’s) SmartWay certification, indicating lower greenhouse gas and other emissions. In June 2007, Hertz bolstered its green offerings significantly by incorporating some 3,400 Toyota Prius hybrids into its American rental fleet.

Meanwhile, other companies are towing the line as well. Avis and its partner Budget offer 2,500 hybrids (Toyota’s Prius and Nissan’s Altima) for rent in the U.S. And Advantage Rent-a-Car, a smaller but up-and-coming player in the industry, has pledged to turn 100 percent of its rental fleet “green” by 2010.

Not to be outdone, Enterprise-the nation’s largest rental car company with a total fleet of 1.1 million rental vehicles-offers some 440,000 vehicles that get 28 mpg or better in highway driving. Some 5,000 of the total are hybrids (Toyota’s Camry and Prius and Ford’s Escape SUV), while another 73,000 can run on the ethanol-based biofuel or on regular gas. Customers of Enterprise (or one of its sister brands, Alamo or National) can also opt to pay an extra $1.25 per rental to offset their carbon emissions. (Funds go to Terra Pass, which funds clean energy projects.) And last year the company opened several new “green branches” where 60 percent of the vehicles for rent are hybrids or other fuel efficient models.

Of course, green car rentals do come with a premium. Renting a hybrid typically costs $5 to $15 more per day than an equivalent conventional car. In a recent comparison on overall costs (including gas expenses), SmarterTravel.com’s Sarah Pascarella figured that a two-day trip from San Francisco to Yosemite National Park was $55 cheaper in one of Hertz’s Hyundai Accent economy cars than in a hybrid Prius from their Green Collection. Comparisons with vehicles from Avis and others yielded similar results. “I found choosing an economy car over a hybrid was often the more economical choice,” she reports.

In order to encourage greener rentals despite the cost premium, San Francisco International Airport now offers travelers a $15 credit if they rent a hybrid from any of the companies operating there. Elsewhere, in-town rental locations usually offer better deals on hybrids, although customers should still expect to pay a premium for renting green no matter where they are-at least until both supply and demand for such vehicles rises, which will inevitably lead to price reductions.

CONTACTS: Hertz, www.hertz.com; Avis, www.avis.com; Advantage, www.advantage.com; Enterprise, www.enterprise.com, EPA SmartWay, www.epa.gov/smartway/; Terra Pass, www.terrapass.com; SmarterTravel.com, www.smartertravel.com.

Dear EarthTalk: Are any major brands of disposable tissues, paper towels, napkins and toilet paper yet using recycled content and chlorine-free bleaching? — Sylvia Comstock, Montpelier, VT

Not many. In fact, some of the biggest names in disposable paper products are the worst offenders. According to the nonprofit Natural Resources Defense Council (NRDC), forests at home and abroad are being destroyed to make toilet paper, facial tissues, paper towels and other disposable paper products. Giant paper producers such as Kimberly-Clark (Scott, Cottonelle, Kleenex and Viva) and Procter & Gamble (Puffs, Charmin and Bounty) are, in the words of NRDC, “forcing the destruction of our continent’s most vibrant forests, and devastating the habitat for countless wildlife species in the process.”

Much of the virgin pulp used by these large manufacturers comes from Canada’s boreal forest. Some 500,000 acres of boreal forest in Ontario and Alberta alone-key habitat for caribou, lynx, wolves and scores of birds-are felled each year to provide pulp for disposable paper. Beyond wildlife concerns, Canada’s boreal forest, which stretches from coast to coast, comprises perhaps the world’s largest terrestrial storehouse of carbon dioxide, so it is critical to keep it intact to help mitigate global warming.

Kimberly-Clark uses some 1.1 million cubic meters of trees from Canada’s boreal forests each year to produce 465,000 metric tons of pulp. Only 19 percent of the pulp it uses to make home use disposable paper products comes from recycled sources. Some of its brands, including Kleenex and Scott, contain no recycled content whatsoever. Nor do Procter and Gamble’s Bounty, Charmin or Puffs, says NRDC.

Another issue with tissue (and paper overall) is the use of chlorine for whitening. Chlorine used in many bleaching processes contributes to the formation of dioxins and furans, chemicals that end up in our air and water and can cause cancer. Safer processes use oxygen compounds and result in paper that is “totally chlorine free,” “process chlorine free” (chlorine free except for recycled fibers that were previously chlorine-bleached) or “elemental chlorine free,” which substitutes safer chlorine dioxide for chlorine.

NRDC and other groups are pressuring the tissue products industry to change its ways, and are working to educate consumers about their options when buying tissue paper products. NRDC’s online “Shopper’s Guide to Home Tissue Products” offers reams of free advice on which brands to look for-and which to avoid. Marcal is the only household name that NRDC rates high on paper sourcing (100 percent recycled and 40 to 60 percent post-consumer content) and chlorine use (process chlorine-free). Brands ranking highest (up to 80 percent post-consumer content and process-chlorine free) include 365 (the Whole Foods brand), Seventh Generation, Earth First, and Planet, among others. No brands are totally chlorine free.

In general, consumers should seek out brands that specifically tout use of 100 percent recycled materials with a high percentage (40 percent or more) of post-consumer waste, and not just keywords like “green” or “eco” on their labels, which may be misleading. Also, before you even purchase that next roll of disposable paper think about how you can reduce the amount you use in the first place. Paper tissues, towels and napkins, for example, have re-usable options in handkerchiefs and cotton towels and napkins.

CONTACTS: NRDC Shopper’s Guide to Home Tissue Products, www.nrdc.org/land/forests/gtissue.asp; Kimberly-Clark, www.kimberly-clark.com; Procter & Gamble, www.pg.com.

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