Precautions while using gray water
Never store untreated gray water for reuse. If allowed to sit, gray water quickly turns into a stagnant, sludge-filled concoction of bacteria and pathogens; these elements thrive on some of the same nutrients a garden could benefit from. This feeding frenzy needs to take place in the soil, as described above, not in your tank. If gray water is collected and stored without treatment, it effectively becomes black water in as little as 24 hours.
A few points need to be kept in mind before using untreated gray water for any of the applications as mentioned previously. Traditionally,waste water from washing of utensils was freshly directed to a a shallow soak pit for mechanical filtration through a layer of sand and gravel topped up with some wood ash. This setup prevents any microbial growth. Further, Planting a bunch of water purifying flora such as Canna Indica or Ginger Lily that supply oxygen at root zone and help in further purification of water.
But in Modern setups with paved surfaces and multistory building untreated gray water if collected is often used for feeding plants or if its clean enough can be used for washing outdoors or floors.
It's important to remember that plant life varies greatly, and some species are unable to deal with the chemicals, salt or acidity levels in gray water. In many situations, drainage from kitchen sinks and dishwashers is too contaminated by grease and high acidity to be used at all without some treatment.
If the household chemicals in gray water are kept to a minimum, most plants will be able to handle it. You can keep chemical contamination to a minimum by using environmentally friendly, biodegradable soaps and detergents whenever possible.So what ingredients in soap cause the most problems for plant life?
The three prime suspects are sodium, chlorine and boron. Some plants may be harmed right away; others are damaged slowly, as elements have time to build up in the soil. If you're intending to use soapy water in the garden, choose cleaners that don't contain this particular trio. Additionally, while your plants can absorb low levels of phosphorous as nutrients, the high volumes found in some soaps can be harmful. Luckily, there are a number of low-phosphate soaps available.
Untreated Gray water should not come in contact with any fruits and vegetables due to the contamination risk (especially if the produce may be consumed raw). Fruit and nut trees are generally considered safe picks to be watered with gray water due to the distance between the ground and the food, but all other food gardens are best irrigated with white water or rain water.
To further prevent contamination, don't store gray water for reuse. If allowed to sit, gray water quickly turns into a stagnant, sludge-filled concoction of bacteria and pathogens -- these elements thrive on some of the same nutrients a garden could benefit from. This feeding frenzy needs to take place in the soil, as described above, not in your tank. If gray water is collected and stored without treatment, it effectively becomes black water in as little as 24 hours.
When pipes are used to divert gray water, take care to prevent pumps and filters from clogging with bits of hair, skin and food. When clogs do occur, it is worth remembering that chemical clog removers are just the kind of harsh chemicals you don't want to send directly into your garden. Natural solutions, such as boiling water or vinegar and baking soda treatments, might be less damaging to plant life.
Above all, all these precautions are not to demotivate you from conserving gray water but to encourage you to do it in a right way. Explore rest of the articles in the "water" series by clicking on "Next article".