Safe drinking water

Some 1.5 million children under the age of five die in India every year because of water-borne diseases. While most people know that bad water causes sickness, relatively few know that water carries diarrhoea, cholera, and stomach disorders. Rural women are the principal collectors, storekeepers, and users of water at home and in communities. Therefore, they must know how to ensure that the water they use is safe.

What is safe water?

Water is safe when there is nothing in it that can cause a disease. Safe drinking water must be:

- Free from harmful germs (bacteria, parasites, viruses, etc.)
- Free from harmful chemicals (such as pesticides) and foreign matter (such as dirt)
- Pleasant to taste or tasteless
- Colourless or crystal clear
- Odourless

Importance of safe water

Not all water is safe for human use-drinking and cooking. Contaminated water can be dangerous to health. It is a source of deadly diseases such as cholera, diarrhoea, dysentery, gastroenteritis, typhoid, jaundice, polio, guinea worm infestation, worm infection, and other health problems.

What causes contamination in water sources?

Human excreta-faeces and urine Animal excreta-dung and urine Bathing, washing, and cleaning activities Industrial effluent from mines, mills, refineries, etc. (Dead fish seen frequently in water might indicate the presence of chemicals.) Wastes from cities Improper garbage and waste disposal Pesticides and fertilizers washed into rivers and groundwater Dead and decaying animals and plants, especially in stagnant water Soil erosion

Due to these pollutants, water becomes unsafe for domestic use and, therefore, unsafe for drinking.

How to recognize unsafe water

Unsafe water has various harmful chemicals (such as iron and fluorides), germs, and waste materials. Harmful chemicals and germs cannot be seen with the naked eye but can cause unpleasant odour or taste.

Note

To be sure, get your water tested. Take a sample of water for testing to your local water-testing laboratory.

Note

Wells should be situated away from sources of contamination.
Water from hand pumps can become contaminated in the rainy season.
Prevent surface water from entering wells.
Keep washing areas and sources of contamination downstream from your water source.

Unsafe water has:

- unpleasant, biker or salty taste might be due to excess of iron and various salts like chlorides.

- foul smell-might be due to gases, germs, sewage, and/or algae.

- cloudy or turbid appearance might be due to excess of mud, clay, salt, iron, decaying organic matter, dyes, etc.

In general:

- running water is safer than stagnant water.

- groundwater is safer than surface water.

- covered wells and hand pumps are safer than open wells, tanks, and ponds.

- tubewells are safer than open wells.

- deep wells are safer than shallow wells.

Can you identity the sources of contamination In this picture?

Source: Notional Drinking Water Mission, Government of India

Maintenance of community water sources

Any water source is a valuable property of the entire village. Therefore, it is everyone's responsibility to guard the water source from contamination.

Taps and water pumps

- Keep the tap and pump and the surrounding area clean.

- Make a drain to lead excess water away from the tap or pump.

- Excess water can be used to water a field or kitchen garden, or can be drained into a soakage pit. This prevents the surrounding area from getting muddy.

- Clean drains regularly.

- Repair cracks in concrete. Repair cracked or damaged pipes promptly.

- Protect the water source, piping system, and storage tank from contamination by people, animals, agricultural and industrial waste.

- Prevent children from putting their lips on the tap or pump when drinking water.

- Bathe and wash clothes at least 15 m away from the tap or hand pump.

- Make a fence around the tap or hand pump to keep cattle and other animals away.

- If it is necessary to water cattle from the pump, make a special cemented trough some distance (about 15 m) away from the pump.

- Turn off taps after use. Do not waste water.

Watering a kitchen garden.

Bathe and wash clothes at least 15 m away from the tap or hand pump.

Wells

- Sink wells in good soil at least 15 m away from possible sources of contamination, such as cesspools or insanitary privies.

- Fill in all hollows, rat holes, foul tanks, cesspits, etc., near the well.

- The site should be sufficiently high to prevent water from flowing toward and seeping into the well.

- Provide a parapet wall around the top of the well about 1 m high to prevent surface water from entering the well. The top of the well wall should slope (should not be horizontal) to discourage people from sitting or washing clothes on it, and thereby contaminating the water.

- Cut down or trim trees and vegetation close by so that leaves and bird droppings do not fall into the well. Tree roots should not be allowed to sprout from the lining of the well.

- Cover the well to prevent leaves and dust from blowing inside.

Prevent sparrows and pigeons from making their nests in the lining of the well.

Provide a proper washing and bathing place at a distance from the well and preferably at a lower level than the well so that waste water flows away. Waste water seeping into the ground close to the well can contaminate the well water.

- Provide a cemented area around the well at least 2 m in diameter. Make it slope away from the well so that surface washings flow away from the well and not into it.

- The buckets of individual users might be dirty and contaminate the well water. So, discourage users from lowering their own buckets into the well.

- Attach a strong bucket with a chain or rope to the well permanently for public use. Keep this bucket clean.

Tanks and ponds

If possible, do not use water from tanks and ponds for drinking. Use well water instead. If you must use water from tanks or ponds, try to follow these guidelines.

Select sites with good surroundings with no insanitary conditions or bore-hole latrines in the vicinity.

Ensure that banks are properly sloped and planted with grass.

The tank or pond should be ringed by an embankment to prevent water from flowing in.

Do not allow surface drains to empty into the tank or pond.

Fence the tank or pond to keep away cattle.

Keep one tank for drinking water and another for other activities, such as washing, bathing, and watering animals.

Draw water without going into the tank. Draw water from the steps or by means of a hand pump.

Plant trees only at a distance so as not to attract cattle and bird droppings.

Remove weeds and algae regularly.

Clean the tank or pond regularly and re-excavate when dry.

This will increase its capacity as well.

Do not allow any commercial activities, such as jute steeping in the tank.

Source: National Drinking Water Mission, Government of India, Mr. Yash Pal Bedi and Directorate of Advertising and Visual Publicity, Government of India

Management of drinking water for the household

You must ensure that the water you use is safe. Take care to prevent contamination from the time water is collected to the time it is used.

Hands are a major source of water contamination. So, do not put your hands in the drinking water and do not let drinking water splash or pour over your hands during collection, transportation, or storage.

Water container

- Clean your water containers with ash or cleaning powder. Do not use mud as it contains harmful bacteria which can contaminate your water.

- Do not use containers which previously contained pesticides, chemicals, petrol, or other poisonous substances.

Collecting water

- Avoid collecting stagnant wafer from ponds. Collect water from wells rather than from surface sources. If, however, this cannot be avoided, strain the water through two layers of cloth. Allow the water to stand for a short while. The water can then be purified with bleaching powder or by boiling. (See Safe drinking water and Some simple ways to purify drinking water.)

Clean your hands thoroughly before filling the water container.

- Do not lower your container into the well. Use the community bucket fixed the well for this purpose.

- Do not place this community bucket on the ground.

- Do not walk down the steps of the well (in the case of a step well) to collect water. This spreads guinea worm. (See Maintenance of community water sources.)

Transporting water

- Carry drinking water in a covered container.
- Make sure that the cover is clean.

Storing water at home

- Keep the water container covered.

- Keep the water container on a high platform out of reach of children and animals. Clay pots and other porous containers must be raised slightly off the ground to prevent contamination.

- If possible, use a container with a tap near the base. This prevents contamination from hands and utensils dipping into the container. It also allows sediment to settle to the bottom.

- If possible, empty and clean household water storage containers daily.

- Use some simple methods to purify your water before use. (See Some simple ways to purify drinking water.)

- Use a clean, long-handled ladle to take water from the container.

Sources: National Drinking Water Mission, Government of India, Mr. Yash Pal Bedi and Directorate of Advertising and Visual Publicity, Government of India

Some simple ways to purify drinking water

Drinking water is not always safe. Sometimes it can carry debilitating diseases, even death. To prevent infection by waterborne diseases, follow the simple techniques given below.

Boiling

Boil all drinking water for at least 10 minutes. Boiling kills most of the harmful organisms present in water. In case boiling is a problem-because of high fuel costs or lack of fuel-boil at least the water for children, older people, and sick people, especially during the rainy season. To improve the taste of boiled water, stir it vigorously with a clean spoon or pour the water from a height, from one container to another several times.

Container	Water quality
Brass, copper	very good
Plastic, glass	good
Steel, iron	not good
Tin, hindalium	bad
Mud, aluminium	very bad

Copper or brass vessels

If possible, store water in copper or brass vessels.

Copper and brass inhibit the growth of bacteria.

Solar disinfection

1 Leave water containers for some time so that heavy dust and dirt particles settle to the bottom.

2 Pour the water into transparent plastic, coloured glass, or blue-tinted glass vessels or bottles. As you pour, be very careful not to disturb the sediment.

3 Cover the vessels and cap the bottles.

4 Expose them to strong direct sunlight for at least 90 minutes. If possible, put the vessels in the sun early in the morning and leave them out until late afternoon. This destroys bacteria that cause several common diseases. Keep the vessels slightly away from each other for direct radiation.

Transparent plastic and colored glass vessels

This solar-disinfected water can be used directly or kept overnight to cool.

Three-pot system

Unsafe, dirty water can be made much safer simply by storing it for at least 24 hours Within that time most of the dirt will sink to the bottom.

1 Take two big pots and one small pot. Use the big pots for fetching water on alternate days.

2 Allow the water in the first pot to stand for 24 hours.

3 Then, pour the clear top water into the small Pot for drinking.

4 Use the remaining water for washing.

5 Clean and refill the first pot when it is empty.

6 Again, allow it to stand for 24 hours.

7 Use the second pot in the same way as the first. In this way, each day's drinking water has been left to stand for at least 24 hours.

Double-layered cloth

Cloth filters

Cloth water filters can be used to strain insects, worm larvae and other comparatively large particles from water. Make a simple two-layer filter using cloth of two different colours so that you know which side to place on top (to receive unclean water). Use tightly woven cloth. Wash the filters after each use. This prevents organisms and debris caught in the filter from recontaminating the water. You can also buy readymade, cheap plastic filters.

Cloth filters

Charcoal filters

Charcoal water filters can be used to remove suspended material and harmful bacteria in polluted water to a level satisfactory for human consumption.

Water-filter pot

Materials

- Gravel and sand for filtration.
- Charcoal to remove colour, odour, taste, and certain dissolved impurities

Construction

1 Make a number of small holes in the bottom of a galvanized iron or steel drum, clay pitcher, or ordinary steel drum. This will be the water-filter container.

2 Fill the pitcher or drum with a 25-cm layer of gravel.

3 Place a layer of coarse sand on top of the gravel, up to a height of about 25 cm.

4 Cover with charcoal.

5 Cover the charcoal with a 510-cm thick layer of gravel to prevent the charcoal pieces from floating in the water.

Chemical disinfection

Chlorine in one form or another is the most common chemical used for disinfection of water It is normally effective against bacteria commonly associated with water-borne diseases It is, however, less effective against certain cysts, ova, and viruses

Chlorine is supplied as a gas, in solution, or as a solid. Probably the easiest form of sterilization of emergency water supplies is by use of either calcium hypochlorite (ordinary bleaching powder) or sodium hypochlorite (available as a liquid).

Notes

- Wash the materials before filling the filter container.

- About three-quarters of the drum should be filled with the filter material. Place this water-filter container on top of another iron or steel drum or clay pitcher, fitted with a tap. Pour water in the top. Filtered water is obtained through the tap at the bottom. The charcoal should be replaced after six months. The sand and gravel can be washed and reused.

- You are advised to add a few drops of chlorine solution (5.25 percent) to disinfect each jug of water.

Chlorination at home

Make a chlorine solution by mixing 1 cup of laundry bleach in 3 cups of water. Add 3 drops of this solution to 1 litre of water and allow the water to sit for 30 minutes. Alternatively, you can treat water using chlorine tablets which are available in the market.

Chlorination of community wells
Continuous disinfection of well water can be done using low-cost devices called "pot chlorination "

Single-pot chlorinator-for larger wells

1 Take a 12- 15 litre earthen pot.

2 Make two holes 0.6 cm in diameter in the middle of the pot.

3 Pour into the pot a moist mixture of 1.5 kg bleaching powder and 3 kg coarse sand. (The mixture should occupy the volume of the pot below the level of the holes).

4 Cover the mouth of the pot with polythene.

5 Lower the pot into the well with a rope so that it remains 60 cm below the surface of the water.

Single-pot chlorinator

This unit can chlorinate wells holding 9,000-13,000 litres of water with a withdrawal rate of 900-1,300 litres per day (sufficient for 40-60 people per day) for a period of at least one week. The treated water has a chlorine content of 0.2-0.8 parts per million.

Double-pot chlorinator-for small household wells

Use of a single-pot chlorinator in a small well (4,000 litres of water with a withdrawal rate of 360-450 litres per day) will result in over-chlorination. Instead, use a double-pot chlorinator.

1 Take two cylindrical pots-one to fit inside the other.

Double-pot chlorinator (cutaway view)

2 Make a 1 cm diameter hole in the side of the smaller pot, about 8 cm below the rim.

3 Fill this pot to just below the hole with a moist mixture of 1 kg bleaching powder and 2 kg coarse sand.

4 Make a hole 1 cm in diameter, about 4 cm from the bottom of the big pot.

5 Put the small pot inside the big pot.

6 Cover the mouth of both pots with polythene.

7 Lower the unit into the well with a rope so that it hangs 1 m below the water level. This chlorinator gives 0.3-0.5 parts per million of chlorine over a period of 2-3 weeks.

Sources: National Drinking Water Mission, Government of India, Mr. Yas Pal Bedi, and Directorate of Advertising and Visual Publicity, Government of India

Calculating volume

Use this formula to calculate the volume of water in your well:

3 x radius of the well (cm) x radius of the well (cm) x depth of water (cm) = cubic cm

Use of indigenous plants for cleaning water

Farm women in India possess a wealth of indigenous knowledge. Women in some parts of India, for instance, use various plants to make muddy water clear.

Moringa oleifera drumstick, sainjana, sahjana
Moringa oleifera can make muddy water clear in 1-2 hours.

Dosage

Use about 30 seeds in 40 litres of water. Use more seeds to clear very muddy water. Dosage can also depend upon the condition of the water source and the season. ( 1 1/2 seeds per litre of water for very muddy water and 1/4 of a seed in one litre of water for less turbid water.)

Method of preparation

1 Remove the wing and coat of the seed.

2 Crush the white kernel in a mortar.

3 Mix the powdered kernel with a small amount of potable water in a glass and stir vigorously for 5 minutes.

4 Pour this suspension through a tea strainer or muslin cloth into turbid water.

5 Keep stirring the water slowly for about 10 minutes.

Strychnos potatorum nirmall The ripened seeds of Strychnos potatorum can be used to make a natural flocculent for cleaning muddy water-dirt particles flock together, creating larger clumps which can be easily removed.

Dosage
Use about 1.5 mg of seed extract per litre of muddy water.

Method

1 Crush ripened seeds into a thick paste using clean water.

2 Add the paste to muddy water and stir.

3 Let it stand.

4 Strain through muslin or pour off the clear water into a clean vessel. Be careful not to disturb the sediment.

(The same results can be achieved by rubbing the seed on the inner surface of an earthen water vessel before filling.)

Semecarpus anacardium bhela, bhilawa

This seed is used in Central India as a substitute for Strychnos potatorum. Rub the seeds on a stone and make a thick paste. Mix it with muddy water. Follow the same procedure as for Strychnos potatorum.

Vetieria zizanoides khus, vetiver grass

Take a clay jar with a few tiny holes in the bottom. Lay wiry roots of the rhizome at the bottom of the jar. Water filtered through this layer of roots is not only cleaner but also has a pleasant smell. (Practiced in South Kerala.)

Tylophora indica jangli-pikvan

The dry roots of this plant improve the quality of drinking water. The roots can be placed directly in water or powdered and stirred in.

Limnanthemum cristatum This herb is grown in rainwater harvesting tanks in some parts of Rajasthan for cleaner water and pleasant taste.

Vetiveria zizanoides

Source: Consortium for Rural Technologies (CORT)

Soakage pit for proper disposal of waste water

Note

Do not use your soak pit for disposing of waste water from latrines.

Day-to-day household tasks, such as cleaning, bathing, and washing clothes, produce waste water. Stagnant pools of water around houses, in the streets, and in choked drains are a health hazard.

Besides producing bad odour and making areas muddy, stagnant pools become breeding places for mosquitoes.

Kitchen gardens are a good place to dispose of waste water. However, if you don't have space for a garden, building a soak pit is a practical, effective alternative.

Soak pits work like this: waste water gets dispersed in the specially designed pit and is absorbed in the subsoil, while pieces of solid waste naturally decompose. Since decomposition takes place in a sealed pit, no foul smell is produced.

Materials required Stones (large, medium, small): 1 cart load Plastic or metal perforated plate (15 cm diameter): 1 PVC pipe (30 mm diameter) 75 cm - 1 m Cement: 2 kg Bricks: 12 Polythene or gunny bags: 4 Sand: 2 cubic ft Masonry and labour charges (digging, fitting, and finishing construction of the pit): 1 day

Construction

Select a 1 sq m area close to the drain outlet, and 30 to 60 cm away from the nearest wall of the house.

- Dig a pit 1m x 1m x 1m x.

- Fill the pit with big stones (coconut size) up to 30 cm, followed by medium stones (guava size), from 30 to 60 cm, and small stones (wainut size) from 60 to 90 cm.

Note

In case the distance between the drain outlet and the soak pit is greater than the recommended distance of 30 to 60 cm, the length of the drain pipe has to be increased accordingly.

Note

During heavy rains, cover the trap with a plastic sheet to stop the rainwater from draining in.

Choose a drain pipe (PVC, bamboo or any used rubber tube or hose) 5 mm in diameter. Cut it to a length of about 75 cm

Make a hole 3 cm in diameter at one end of this pipe.

Construct a brick-lined trap below the drain outlet of the house, install a perforated plate and a drain pipe running down to the soak pit.

Construct a brick-lined trap

The principal/function of the trap is to keep solid deposits, rainwater, and mud out of the soak pit. You can also use a clay pot with holes in the bottom as a trap.

- Install the drain pipe so that the end with the 3 cm hole reaches the centre of the pit and the perforation faces downwards.

- Cover the pit with a polythene sheet (fertilizer bags or cement bags). Make sure that the cover stretches at least 15 cm beyond the sides of the pit. Spread earth on this cover and pack it until the surface of the pit is level with the ground. Make the finished surface look the same as the surrounding area.

Maintenance

Daily-Remove solid deposits held in the trap and flush a litre of water through the trap to clear any blockage.

Periodic-In time, your soak pit might become choked. Excess moisture on top of the soak pit is - an indication of choking. When choking occurs, dig out the soak pit and remove the stones and debris. Wash the stones and refill them in the pit.

For an average family, a well maintained soak pit will last for at least five years.

Contributor: Dr. N. Kamalammo

Efficient use of irrigation water

Note

Different size jaltriptis can be made to suit your needs.

Plant

Rural women travel long distances for fuel, food, and fodder. This work can pose great hardship, especially in arid and semiarid regions where trees and crops are scarce. Irrigation is an obvious solution, but providing enough water to nurture crops and trees on dry, sandy soils is difficult. There are techniques and tools, however, which can help.

Jaltripti

Growing trees is difficult in arid and semi-arid regions, especially in high percolation sandy soils. A simple device called a Jaltripti can reduce the frequency of waterings and reduce the total amount of water needed, while ensuring a constant regulated supply of moisture to young trees.

Construction

The jaltripti consists of a double-walled earthen pot. It is made by placing one pot inside a larger pot. See box at left.

The base (but not the sides) of the inner pot is coated with paint, cement, or coal tar to keep water from passing through.

Method

- Dig a hole and bury the jaltripti up to the rim of its outer pot.

- Fill the inner pot with good soil.

- Transplant the sapling into the inner pot.

- Fill the space between the two pots with water.

- Cover this circular water reservoir with polythene sheet to reduce evaporation. Do not cover the sapling.

- Fill the jaltripti with water every week or so, depending on the season and the size of the pot.

Pitcher method

The pitcher method makes good use of water. It is best suited to dry areas with light soils, but can be adapted for use anywhere. It is particularly useful for growing melons, gourds, pumpkins, and other trailing plants.

- Dig holes 70 cm wide and 70 cm deep.
- Add 18 kg of composted manure to each hole.
- Add 18 kg of soil to each hole and mix well.
- Bury an earthen pot with the mouth of the pot at ground level in the middle of the bed.
- Fill the pot with water up to the brim.
- Cover the pot.
- Plant four seeds around the pot.
- Refill with water whenever the water level decreases.

Circular gardens

Circular gardens are best suited to drought areas and where land is scarce. They use little water.

Method

- Dig holes 30 cm in diameter and 30 cm deep.
- Build bunds around the rims of the holes.
- Plant seedlings inside the holes.
- Water close to the stem of the plant.

Sprinkler irrigation

This method is used for medium and large farms. It is more efficient on coarse texture soils, such as sand and sandy loams, which have low moisture-holding capacity. It is especially useful on undulating land and sand dunes.

The water is sprayed on the crop at a controlled rate. It can be used for almost all crops and is very popular for cash crops and some orchard crops.

Spray irrigation is advantageous on some soils with salinity problems. It leaches salt effectively, and promotes seedling emergence and growth.

The spray cools the crops during high temperatures and controls frosts during freezing temperatures.

Some sprinkler systems are portable. A system costing Rs 1520,000 to install can irrigate 5-10 ha in one crop season.

Drip irrigation

Drip irrigation involves the slow application of water, drop by drop, to the root-zone of a crop.

Water is used very economically, since losses due to deep percolation and surface evaporation are reduced to the minimum.

This system is suited to arid regions. Growing orchards on saline soil is possible using the drip system.

Sources: Ms. Chitra Mani, Mr C. V. Sheshadri, and CDRT Allahabad