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Frequently Asked Questions
How dangerous is gray water? What can I do about it? Gray water is inherently unsanitary. It may contain bacteria, fungi, viruses, or other life. Gray water left to stand untreated in the desert warmth eventually becomes black water as microbial populations increase. To disinfect gray water, and suppress funky aromas, mix in Concentrated Clorox Regular Bleach or other chlorine-based bleach periodically. For some antibiotic-resistant pathogens, chlorine bleach is the only reliable killer. The active ingredient in chlorine bleach is sodium hypochlorite - a powerful disinfectant that decomposes into water and salt. Age, sunlight, warmth, and gray water impurities (including playa dust) all increase the rate of decomposition, soon exhausting the disinfecting power. Make sure your bleach is newly purchased, not left over from last year.
How much bleach do I need to disinfect? The following rule will help compensate for all these uncertainties. Use the No-Measure Rule of Thumb for Disinfecting: Follow Your Nose.
Loosen the cap of your bleach jug one-half turn: no farther, or it may come off. Using your thumb to restrain the cap, tip the jug over your gray water and dribble for about two seconds per gallon. Slosh or stir to mix, and half an hour later, sniff. If it doesn't have a strong chlorine tang (like a public swimming pool) dribble in more bleach and check it again later. Make this a morning and evening habit.
When buying chlorine bleach, check the label for the concentration of sodium hypochlorite. Concentrated Clorox Regular Bleach has about 9%. If another brand has 6%, it should cost two-thirds as much and you'll need to add 1.5 times as much. Scented products are always lower in hypochlorite. Bleach has a limited shelf life, and this year's leftover jug won't last until next year.
Disclaimer: We are not sanitation experts, but an expert at Clorox Corp reviewed this text. Following the guidelines above is not guaranteed to fully disinfect your water.