Zero Water Day – possible implications and Issues

Hi Stefan.

Both for the near and long-term try to build water resilience into your household. By that I mean local storage under your direct control coupled with all sensible measures to reduce consumption and to re-use your grey water. Here are some suggestions based on what I and many others are doing and have done.

1.) Install tanks gathering water from roof gutters. Go to the UCT site http://cip.csag.uct.ac.za/webclient2/waterharvest/ to model your household’s situation and determine what size tank(s) to install. If you can afford it, buy two tanks (failsafe) interconnected, with total capacity 60 (days) x 20L x nr ppl in your family; 4 pers family = 4800 L = (2x 2500L tanks). Rule of thumb – 1mm rain falling on 1sqM roof area produces 1L water x ?80% efficiency. So 10mm falling on 150sqM should produce 1200+L. Should still get enough rain during rest of winter to fill the tanks. Keep second tank as a minimum 30day “iron reserve” and use first tank if/as needed, refilled periodically by rain. In extremis one can drop to 10L/pers/day so this storage can actually last 3-4 months. And depending where you live, CT invariably gets some rain every month sufficient to replace most usage at 10L/p/d. Dose the tanks periodically with with 100ml Jik or Miltons and toss into each a few Tblspoons of vegetable oil to coat the surface and discourage mosquitoes, etc. Use gravity or if needed install a pump and piping to lead this water to separate taps in bathroom, kitchen and laundry for very controlled use. Boil this water before consumption. Install lockable valves on the tanks. Display required “non-potable” signage (at least for now).
2.) If you are in a suitable area, do install a well. This can give 500 L/day or more and water is suitable for all secondary uses. Tend to dry up around Feb/Mar as the water tables drop but quickly recharged when rains commence around May/Jun. If you do, then split the tanks, pump well water to one for general use and keep rainwater in other tank for consumption and personal use. Mineralisation can give issues.Installer will be able to advise.
3.) Create some form of sump (brick built sealed, metal, lined pit or whatever) low down on the property to which one can lead any other rain run-off e.g from garages, yards, driveways, etc thereby gathering useful water for undemanding use (e.g. toilet flushing). Pump this water through a filter back up to a conveniently located drum with a tap from which water can be drawn for general use.
4.) Take all possible steps to reduce consumption habits down to 20L or less per person per day.
– Reduce laundry to minimum (air and re-use outer clothes, bedding).
– Wipe all plates and dishes with paper before cleaning in basin with hot boiled water. Air dry. If using dishwasher wipe all first then pack washer to fullest before using econ cycle every 2nd day.
– Shower every second day; catch warming water in bottles/jugs for kitchen use; standing in a plastic basin, damp all over, water off, soap lightly using a flannel cloth, water back on to rinse. On other day use household spray bottles to damp all over, wipe with lightly soaped flannel for minimum soapiness, spray again and wipe off with soap-free flannel. Shower water goes to flush toilet or garden.
– Minimise toilet; boys pee in buckets, dilute then water plants; girls use toilet but let mellow, only flush once something darker is deposited; use only one toilet in the house, refill cistern with shower water. [If it gets really bad, one may need to use camping style toilets or perhaps even dig long-drops in the garden.]
– Generally; grey or sump water for toilets and garden; use sump or rain water for all general cleaning; rain water for personal washing and laundry; municipal, bottled or boiled rain water for consumption/cooking.
5.) Write off most of the garden. Keep trees and shrubs alive with sump and grey water and a small patch of lawn and a few flower beds to help keep one sane (and use up grey water). Create furrows to redirect rain run-off to plants and beds. Definitely create a vegetable area (near to laundry to facilitate piping grey water to garden) and plant some essentials (spinach, lettuce, tomatoes, potatoes, pumpkin, butternuts, onions, celery, cauliflower, aubergines, a few favourite herbs, melons); it doesn’t take much area, adds interest, saves money and uses worst quality water; sprinkle only around base of plants, not on leaves or fruit; for underground items use only rain or sump water (not grey).
6.) Lastly encourage water saving and capture/storage at one’s place of work, sport, etc if practical. Harvested water can be pumped to toilets and hand basins and be used for washing and cleaning. In extremis can be used to ration 5-10L /day to disadvantaged employees who may have no other source of water.

I sincerely hope that “Zero Water Day” never arrives. But going this route can make your personal household water-resilient, give you great peace of mind, add value to the home, and can pay back the cost within 3-5 years. Apart from anything else you would have contributed directly by reducing your household demand on Muni water to almost nothing. There is not much that we can do about society in general but we only have ourselves to blame if we do not provide for our own requirements.

And if only everyone would take such actions – the water crises would simply disappear as the primary water capture/storage would be at the household level in the towns while the big dams would store years of backup water in the mountains for exceptionally dry times. Enough water falls in the towns to meet all our needs if we just harvest and store it. The big investments could then go into sophisticated recycling of waste and storm water to be used for non-potable purposes. Tapping the aquifers would supply extra water if ever needed and expensive desalination could be postponed for decades or forever.

I suggest act right away. Then become a “water warrior” and spread the word.

Good luck, Tom.