GC: n
CT: How greywater systems work.
Unlike a rainwater harvesting system, which relies on rainfall, greywater is in plentiful supply on a daily basis – the more clean water that you use to wash yourself, your food and your dishes, the more greywater you will have to recycle. But while you’ll find greywater systems in hotels, university hostels and even National Trust properties, it’s rare to find a homeowner utilising a greywater system – or even a manufacturer supplying this market. Why not?
Because greywater, says Jacob Tompkins from Waterwise, must be handled correctly, and at the moment that makes it expensive: “People in the UK are used to the finest quality water in the world coming out of their taps, but water-borne diseases are the world’s biggest killers. The problem with a greywater system is that you have to store contaminated water – water that may have been used to wash meat, wounds or who knows what. That means bacteria will start to breed, and it will start to smell after just three to four days. As a result, you have to treat it like the water companies do, which would normally involve chemical treatment, filtering or using ultraviolet light. All of these options will increase your energy usage, on top of any energy you’ll use pumping the water into a storage tank and back out again around the house.”
S: The Guardian – http://www.goo.gl/79YEk3 (last access: 18 December 2017)
N: 1. – grey (adj): Old English grǣg, of Germanic origin; related to Dutch grauw and German grau.
– water (n): Old English wæter, from Proto-Germanic *watar (cognates: Old Saxon watar, Old Frisian wetir, Dutch water, Old High German wazzar, German Wasser, Old Norse vatn, Gothic wato “water”), from PIE *wod-or, from root *wed- “water, wet” (cognates: Hittite watar, Sanskrit udrah, Greek hydor, Old Church Slavonic and Russian voda, Lithuanian vanduo, Old Prussian wundan, Gaelic uisge “water;” Latin unda “wave”).
2. The relatively clean waste water from baths, sinks, washing machines, and other kitchen appliances.
3. Greywater can be defined as any domestic wastewater produced, excluding sewage. The main difference between greywater and sewage (or blackwater) is the organic loading. Sewage has a much larger organic loading compared to greywater.
Some people also categorise kitchen wastewater as blackwater because it has quite a high organic loading relative to other sources of wastewater such as bath water.
People are now waking up to the benefits of greywater re-use, and the term “Wastewater” is in many respects a misnomer. Maybe a more appropriate term for this water would be “Used Water”.
4. With proper treatment greywater can be put to good use. These uses include water for laundry and toilet flushing, and also irrigation of plants. Treated greywater can be used to irrigate both food and non food producing plants. The nutrients in the greywater (such as phosphorus and nitrogen) provide an excellent food source for these plants.
S: 1. OD – https://en.oxforddictionaries.com/definition/grey (last access: 18 December 2017); OED – https://goo.gl/K87wtF (last access: 16 December 2017). 2. OD – https://en.oxforddictionaries.com/definition/grey_water (last access: 18 December 2017). 3 & 4. https://www.sustainable.com.au/greywater-treatment.html (last access: 18 December 2017).
GV: grey water, graywater (US), gray water (US).
S: TERMIUM PLUS – http://www.goo.gl/hdcfZd (last access: 18 December 2017)
SYN:
S:
CR: black water, wastewater.
