Rainwater

From Antivist

BAD:

Where the primitive rain barrel furnishes family needs and rears mosquitoes

Where shallow cisterns must have holes chopped in the ice and from which the water has to be hauled up in an oaken bucket, or hauled hand over hand, by rope and pail, or a 'chain pump';

Where a deep, unprotected cistern was built without provision for drainage, and has to be cleaned of nasty sludge, dead toads, mice, and other gruesome ingredients every summer.

Where there was a 'filter cistern' which could not be cleaned, because of inaccessibility.

Where at attic tank filled direct from the roof collects leaves, soot, dirt, and bird droppings.

Where the water has to be pumped by hand either to a tank in the attic or a pressure tank in the cellar.

Well water include brownish or whitish scale that forms in kettles because of lime content, magnesia or iron. This scale is a poor conductor of heat, thus making necessary the use of excessive fuel. It also clogs 'waterbacks' in kitchen stoves and 'heating coils' in furnaces, often causes leaks and sometimes explosions. Lime and magnesia form 'curc' or 'sludge' with soap and washing powders and spot or stain clothes being washed, and water that contains iron turns brown upon standing, stains pails, and makes clothes yellow or stained when laundered.

GOOD:

Rain water is superior to most well and spring water and is such a money saver that every farm home should have a supply, of for no other purpose than that for the family washing. It requires no softener, uses less soap, and is pleasanter to work with than even the best water that has come in contact with the ground.

To obtain an adequate supply of rain water for household use, provision must be made to collect it, to eliminate contaminating materials by screening and filtering to provide storage and to make the water readily usable. The roofs of buildings are the most common sources of supply, but they are subject to various types of contamination and since water is a good solvent, it is quickly polluted. Hence, in collecting a rain-water supply the roof must be thoroughly cleaned by rain before any water is allowed to collect in the cistern. also the downspouts always should be disconnected from the cistern at regular intervals. they should be inspected to make sure they are uncontaminated.

The filter cistern is used chiefly to remove foreign matter carried in suspension in the rain water Coarse material such as leaves is first removed by a screen before the water reaches the filter proper. The filter should have surface area enough for sedimentation before filtration; be so constructed that sediment and the filtering material may be easily removed.

The commonest type is the downward flow or gravity style which is better than the uwpard flow style with drains. This is a concrete box filled with alternate layers of coarse gravel, charcoal and sand from which a drain discharges the water when not flowing into the cistern and which drains the filter when not in use. A screen removed all coarse material and a hose or a few pails of water will cleanse the inlet side without disturbing the cistern supply. the easily removable water-tight top is for removal and renewal of the filtering material.

Storage may be above or below ground. Where there is little chance of freezing, the former is satisfactory and where the roof is high, the tank may be placed high enough to give pressure without pumping. Such tanks may be of wood, galvanized iron, etc. and placed inside or close to the house whose roof collects the water. the commonest storage for rain water is the masonry underground cistern. the walls must be made water-tight to prevent leakage and to avoid the entrance of seepage water. Never should it be located near trees because the roots might crack the walls. Trouble of this kind is most likely to occur with plaster-on-earth masonry. cylindrical and rectangular cisterns are both satisfactory. by providing a pipe at the lowest point of the bottom, practically all the sediment may be siphoned out when there is a drain t a lower level or pumped out otherwise.

The cistern should be of a size to serve the amount of people who will use it. 5 gallons daily per person is a fair estimate where amply hard water under pressure is also available for other purposes. Far more should be provided where there is enough roof area to collect it.

33% of the rainfall estimate should be deducted for leakage, evaporation, and to wash the roof. enough storage capacity should be provided to store water that falls during the rainy season to meet needs during the dry time. Better still to have sufficient storage for six months.

Chemical solutions to remove the color from rain-water off of roofs is:

1. dissolve 3/4 pound of baking soda in 1 gallon of water.

2. dissolve 1 pound of alum (potassium aluminum sulphate crystals) in 1/2 gallon of water. (Filter alum may be used) use 1/2 pound to 1/2 gallon of water.

Determine the amount of water in the cistern by multiplying the area by the actual depth of water (1 cubic foot contains 7 1/2 gallons) for each 30 gallons of water, add 1/2 pint of solution #1 and stir. Next add 1/4 pint of solution #2 for each 30 gallons and stir again. Allow 24 hours for the precipitate to settle to the bottom, after which the water above the solution will be clear.

Sludge accumulation in any cistern and should be removed at the time of year when the water is at its lowest point.

In spite of precautions, leaves, mice, toads or insects sometimes get into cisterns and produce bad odors. The proper thing then is to clean the cistern thoroughly. In dry years, when this waste of water may be serious the water may be deoderized and made satisfactory for all uses except drinking by treatment with chloride of lime which burns up the odor. Mix about a tablespoon in a porcelain glass or crockery dish with two or othree tablespoonfuls of water. rub the lumps with a spoon, then add about a quart of water. Stir thoroughly and pour the solution into the tank, mixing it intimately with the cistern water by stirring with a long board or a paddle. If this treatment is not adequate, use a second or third dose if necessary. This chemical is harmless unless used in excessive amounts.

SPRING WATER

When higher than the point of use, pipes placed below the frost line may be laid so the water will flow by gravity. Though the system usually works well, trouble is sometimes met by the gradual reduction and finally the stoppage of the flow. Generally this is because air has collected. Little by little from bubbles in the water and lodged in some irregularity of the pipe. The less the grade, the smaller the pipe, and the slower the flow, the greater the liklihood of such trouble because the bubbles will not be carried down by the current but gradually work back to a high spot.

To avoid difficulty, the pipe should not be smaller than 1". Stand pipes may be tapped in at high spots to allow the air to escape. The entrance to the pipe should be 6" or more above the bottom of the spring well and be protected by a screen to prevent anything but water getting in. The pipe itself should be laid as straight as possible, with neither dips, rises, nor avoidable angels. All joints should be well leaded, and screwed tight so as to cover all the threaded parts.

Water supply parts and supplies can be obtained from local plumbers, such as water rams, regular well pumps, etc.

WATER NOTES

Be aware of water usage. Each toilet flush consumes about 5 gallons Each minute of water running in a sin - 3 to 5 gallons. A ten minute shower uses - 50 gallons Each washing machine load - 30 to 50 gallons Avoid excessive toilet flushing: 

   If its yellows - let it mellow
   If its brown - flush it down

Put a bottle filled with water or a displacement object in toilet to conserve water Put hard rubber plugs for sinks that leak Get an effective water filtration system If bottled water is used, use recyclable containers If you have a lake or lagoon, practice keeping the water and shores clean Get a low-flow device for shower, tub, and sinks Use whatever gray water you can 

  Wash a baby with biodegradable soap. Do hand wash in it, then water plants and flower with it.

Take a bath in 5 gallons of water Use a sponge bath whenever possible Use a basin for washing and rinsing dishes Do not let the water run when washing dishes

Rainwater harvesting is the collection and storage of rain from roofs or from a surface catchment for future use. The water is generally stored in rainwater tanks or directed into mechanisms which recharge groundwater. This is appropriate in many parts of the world, such as western Britain, China, Brazil, Thailand, Sri Lanka, Germany, Australia and India, where there is enough rain for collection and conventional water resources either do not exist or are at risk of being over-used to supply a large population. Rainwater harvesting can provide lifeline water for human consumption, reduce water bills and the need to build reservoirs which may require the use of valuable land.

Traditionally, rainwater harvesting has been practised in arid and semi-arid areas, and has provided drinking water, domestic water, water for livestock, water for small irrigation and a way to replenish ground water levels. This method may have been used extensively by the Indus Valley Civilization.

Currently in China and Brazil, rooftop rainwater harvesting is being practised for use for all the above purposes. Gansu province in China and semi-arid north east Brazil have the largest rooftop rainwater harvesting projects ongoing.

Rainwater harvesting in urban areas can have manifold reasons. To provide supplemental water for the city's requirement, to increase soil moisture levels for urban greenery, to increase the ground water table through artificial recharge, to mitigate urban flooding and to improve the quality of groundwater are some of the reasons why rainwater harvesting can be adopted in cities. In urban areas of the developed world, at a household level, harvested rainwater can be used for flushing toilets and washing laundry. Indeed in hard water areas it is superior to mains water for this. It can also be used for showering or bathing. It may require treatment prior to use for drinking.

Two residences in the city of Toronto, Canada, use treated harvested rainwater for drinking water, and reuse water (i.e. treated wastewater) for all other household water applications including toilet flushing, bathing, showers, laundry, and garden irrigation (Toronto Healthy House).

In New Zealand, many houses away from the larger towns and cities routinely rely on rainwater collected from roofs as the only source of water for all household activities. This is almost inevitably the case for many holiday homes. Contents


Systems

There are many types of systems to harvest rainwater. The type used depends on physical and human considerations.

A mechanism can be used to send the initial water flow to waste, usually the first few liters. These are commonly known as 'first-flush' diverters, and are used to increase the chance that the large-particle residue that might accumulate on your collection surface is washed away from (and not into) your storage tank. Such a system also compensates for the fact that the initial minutes of a rainfall can include airborne pollutants being washed from the sky[citation needed], and likewise minimizes contamination of your captured supply. Simple but regular inspection and maintenance of such a device is usually necessary.

Not all catchment systems use such a feature. For example, rainwater in rural areas of Australia is traditionally used without such a system, and without treatment,[citation needed] but this may be unwise in different environments.

In India, reservoirs called tankas were used to store water; typically they were shallow with mud walls. Ancient tankas still exist in some places.[1]

Rainwater may also be used for groundwater recharge, where the runoff on the ground is collected and allowed to be absorbed, adding to the groundwater. In US, rooftop rainwater is collected and stored in sump.[2] In India this includes Bawdis and johads, or ponds which collect the run-off from small streams in wide area.[3][4]

Quality

As rainwater may be contaminated, it is often not considered suitable for drinking without treatment. However, there are many examples of rainwater being used for all purposes � including drinking � following suitable treatment.

Rainwater harvested from roofs can contain animal and bird feces, mosses and lichens, windblown dust, particulates from urban pollution, pesticides, and inorganic ions from the sea (Ca, Mg, Na, K, Cl, SO4), and dissolved gases (CO2, NOx, SOx). High levels of pesticide have been found in rainwater in Europe the highest concentrations occurring in the first rain immediately after a dry spell;[5] the concentration of these and other contaminants are reduced significantly by diverting the initial flow of water to waste, as described above. The water may need to be analysed properly, and used in a way appropriate to its safety. In Gansu province, for example, harvested rainwater is boiled in parabolic solar cookers before being used for drinking.[citation needed] In Brazil alum and chlorine is added to disinfect water before consumption.[citation needed] Appropriate technology methods such as solar water disinfection, provide low-cost disinfection options for treatment of stored rainwater for drinking.

However, in Metropolitan areas there are other factors that need to be considered to ensure that the rainwater you harvest can be used to its full potential. Water quality is a potential problem with all roof water systems due to: 

   *

     Atmospheric pollution
   *

     Bird and possum droppings
   *

     Insects and other small animals
   *

     Roofing materials and paints
   *

     Detergents and other chemicals (ie fibrous cement roofs - lime contamination)


Deciding why you want to install a rainwater tank? A Plumber can advise how a rainwater tank can: 

   *

     Save you money on water bills
   *

     Help the environment
   *

     Collect and conserve water supplies from the rain
   *

     Help in a fire fighting situation


4 factors which primarily determine the reliability of rainwater tank supply are: 

   *

     Local rainfall patterns in your area
   *

     Roof catchment area and down pipe location (you may only be capturing 1/6 of your roof area)
   *

     Demand for water (there might be a better year round use for the water such as toilet flushing)
   *

     Rainwater tank capacity


Householder / Plumber Checklist 

   *

     Measures to prevent access to children to reduce the risk of accidental drinking and entry into the tank
   *

     Ensure that rainwater is not connected to the reticulated supply, (backflow prevention - dual check valve)

Key design points 

   * Screened inlet to prevent the entry of mosquitoes and debris.
   * A first-flush device to minimize the entry of dust and pollutants which have built up in the atmosphere and on the roof.
   * Cost is an important consideration. Currently rainwater tanks are being promoted and subsidized in places such as NSW, Australia. However, it is also claimed[verification needed] that this is not a cost-effective use of funds, and water recycling (stormwater recycling or sewage recycling) may be more effective.

Rainwater System Designs

Usage

  • Storing rainwater for ready use in containers above or below ground
  • Charged into the soil for withdrawal later (groundwater recharging)
  • rain gardens

Harvesting

There are many types of systems to harvest rainwater. The type used depends on physical and human considerations.

A mechanism can be used to send the initial water flow to waste, usually the first few liters. Low cost versions can be made using a bucket which fills up, the weight of which is used to change the direction of water flow. A small hole in the bucket allows the water to drain before the next rain. These methods avoid most of the impurities collected on the roof, and some of the pollutants washed out of the air.

As rainwater may be contaminated, it is often not considered suitable for drinking without treatment. However, there are many examples of rainwater being used for all purposes � including drinking � following suitable treatment.

Rainwater harvested from roofs can contain animal and bird feces, mosses and lichens, windblown dust, particulates from urban pollution, pesticides, and inorganic ions from the sea (Ca, Mg, Na, K, Cl, SO4), and dissolved gases (CO2, NOx, SOx). High levels of pesticide have been found in rainwater in Europe the highest concentrations occurring in the first rain immediately after a dry spell; the concentration of these and other contaminants are reduced significantly by diverting the initial flow of water to waste, as described above. The water may need to be analysed properly, and used in a way appropriate to its safety.

Rainwater tanks are constructed from materials such as plastic (polyethylene), concrete, and galvanized steel, as well as fibreglass which is rust and chemical-resistant. Tanks are usually installed above ground, and are usually opaque to prevent the exposure of stored water to sunlight, to avoid algal blooms. Tanks are also covered and screened to exclude insects, debris, animals and bird droppings. Tanks often come with a plastic inner lining to both increase the life of the tank and protect the water quality.

Sizes typically range from around 400 litre (105 gallon) capacity to 100,000 litres (26,420 gallons). Larger tanks are commonly used where there is no access to a centralised water supply. Also affecting tank size is predicted rainfall and rainfall variability; the higher prices for larger tanks; intended use of rainwater and typical consumption for these uses; the area of roof draining into the tank; security of supply desired.

Maintenance includes desludging, checking roofs and gutters for vegetation and debris, maintaining screens around the tank, and occasionally removing sediment by draining and cleaning the tank.

Producing Drinking Water from Rain Water

It is possible to produce pure drinking water from rain water using a combination of devices costing around $300 total.

Here's how to do it:

  1. Install a roof washer and a rain barrel ($200). A roof washes diverts the first ten gallons or so of rain water away from your barrel � it contains such things as dust and bird dropping from the roof.
  2. Put the water caught in the barrel into a counter-top ceramic gravity drip filter ($220) or this portable, inexpensive model ($100). The water will be filtered free of cysts, bacteria, metals, pollutants and pollen. (The Red Cross use this type of filter in the field to purify questionable water for drinking.)
  3. Come back an hour later and drink the pure, highly-filtered, rain water from the filter's faucet.

The water than comes out of this system will be purer than commercial bottled water, faucet filtered or tap water. It will retain the taste of rain water because the drip filter does not flatten the taste of the water. You can produce up to four gallons a day.

This is a basic outline of the process. Doulton has the detailed information on Drip Filters. Their site is full of information, although it takes some digging to find. You might want to start with their FAQ.

For extra protection, you can use an ozonator to kill viruses in water smaller than .02 microns. Ozonators use less energy than UV Light, Reverse Osmosis or Distillation.

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