Water

There are a number of general issues we will have to deal with

  • Supply
  • Volume
  • Storage
  • Safety

I’m assuming a standalone house or unit for this, feel free to adjust for apartments and flats.

Since most countries appear to be opting to quarantine in place, meaning basically locking us in to prevent transmission, we need to look at what is entailed in managing for an extended period in our own homes.

Supply

To begin with municipal supplies should be both safe and available and my first task will be to top up storage with tap water. However, if the 3 months course of the disease is realistic, it is entirely possible that the municipal supply will fail.

Alternatives will start with rainwater and the fastest way to obtain that will be a tap into your spouting system. As a rough guide, one millimetre of rain produces 1 litre of water fro every square metre of roof.

I’d be interested in other bulk sources such as using shade sails.

Last on the list would be rivers and streams; apart from the need to leave the safety of the quarantine, the water itself will be highly suspect. If we get down to that we are in serious trouble.

Volume

Rough estimates say 10 litres or 2 gallons per day per person. Depending on your location that may vary, summer in Alice Springs will be different from winter in Hobart, and I suspect that it may be generous. While municipal supplies are available water use should be limited but not stingy, if they go out however, you need to be able to shift rapidly to a very tight water budget.

I’m working on a family basis and trying to break down personal from collective use.

  • Drinking - Personal - 2 litres/day (includes tea, coffee, cordials etc)
  • Hygiene Personal (teeth, washing, hand cleaning) - 2 litres/ day (Forget showers, you are now on a tight regime.
  • Cooking - Collective - 1 litre per person/ day
  • Washup - collective - 4 litres per household/ day
  • Laundry - hand washing of essentials - 5 litres every 3 days.

For a two person house like mine with 2 small dogs, the 10 litres/ person/ day looks about right. That means for a 90 lockin we need to be sure of 1800 litres. Unless you have a rainwater tank, that’s going to be a major call.

For those of us without tanks, does anyone have any idea?

Storage

For parts of the world where rain is regular, it may be safe to allow for a month’s worth of water storage capacity and be assiduous about collecting rainwater as available. Even that requires storage for 270 litres ‘per person’. Supermarkets sell water in 10 litre containers so try to imagine 27 of them for each member of your household and see whether you can store that.

Legally acceptable rain barrels (check your local laws on this) will at least be able to be stored outside or in a garage, but at 55 gallons each a family of 4 will need 5 of them full to cover a single month shut in. If you can afford to get yourself a rainwater system, now might be the time to think about it.

Safety

At some point municipal water will become unsafe as staff are taken down with the flu. With luck you will be told through the media, but in the case where water is cut off and then restored, or there is flooding, and certainly if there is any turbidity in the water, treat it as suspect and shift to local purification.

The first stop could be down to your local second hand clothing outfit to buy a couple of old saris if you can find them. Sari silk, especially used ones, folded to 8 thicknesses is a great first line of defence against general crud and water-bourne diseases like cholera.

The beauty of the sari material is that it is thin and readily available in all villages in Bangladesh. To filter the water effectively, the sari needs to be folded between four and eight times. The folded cloth is then wrapped over the pot used to collect drinking water from ponds or rivers. After the water has been collected, the sari is removed from the pot, unfolded, and rinsed in water and then air dried in the sun for a couple of hours to decontaminate it. This is sufficient to kill bacteria trapped in the material but in the monsoon seasons, an inexpensive disinfectant can be used to decontaminate the material.

The next step will be either to purify the water chemically, which makes sense if you are storing a large quantity ready to use, using either proprietary purifiers available from water management people or through camping and tramping shops.

Second level purification is to use commercial bleach. I have seen recommendations for “one drop per gallon” which is a bit vague, can anyone be more precise about concentration needed? I’ve also seen suggestions that the residue in an empty bleach bottle, filled with water, is enough for most uses. Confirmation please.

Last resort is to take clear plastic PET bottles and carefully fill them with water, making sure that all the air is out. Lid tightly and put them on the roof in direct sun. Depending on your latitude, it will take at least 72 hours for the UV in the sunlight to kill the bugs in the water. If you live in a place where UV warnings regularly run in the extreme danger range, that is you. Everyone else needs to leave them longer.

Although there are no diagrams, Sun and water: an overview of solar water treatment devices has a range of useful information at different levels of cost and sophistication.

Another option being used by the Australian Armed Forces is to mix the water with Raspberry Cordial. I haven’t been able to find an online reference but I trust the source. Since you may want a source of flavour to conceal the taste of the water anyway, as well as provide vitamin C, it could be a win/win/win. Thoughts?

See also http://www.fluwiki.info/index.php?n=Consequences.DrinkingWater

Page last modified on May 24, 2011, at 09:23 AM by pogge