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Module
1.6 1.6 Water Sources and Distribution Systems
Oorani in India – DHAN Foundation
Water can be obtained and distributed from many sources such as rain water harvesting, springs, deep and shallow wells, and surface water. It is suggested that an evaluation be done to select criteria and then choose an appropriate source for water. This module provides an overview of water source systems, storage and distribution.
Module 1.6 Water Sources and Distribution Systems
Water Sources Poverty stricken countries tend to be in the climatic zones most subject to drought and other water problems. The Canadian International Development Agency (CIDA) estimates that there are presently 300 million people living in regions affected by water shortages and that this number will rise to 3 billion by 2025 (CIDA ‘99). Poor countries, with their high rates of population growth, are least able to finance alternative sources of water. Consequently, affordable water treatment which can provide clean water using current water sources could have a huge impact on the lives of millions.
Source Selection Criteria A source for a supply of water is chosen based on several criteria. Frequently there is only one source for a family to access so that is the one they have to use. In other cases, there may be a choice of supplies so the following criteria are used, in some form, to select the source. • Water Quality - How good is it? • Affordability - What does it cost? • Adequacy - Is there enough? • Reliability - How long will it last? • Convenience - How far away? Although groundwater is usually a better option than surface water from a public health engineering standpoint, there is often some resistance by villagers, who have traditionally had a surface water source, to using a new groundwater source. This is most often the case in areas (as in the example below) where the groundwater has a high level of salt, iron or other mineral. But in some cases, people simply prefer the taste of the surface water. (Source: UNICEF WATERfront, Issue 6, pg. 22) Surface Water Tastes Better "It is five PM in the village of Jhadol, Rajasthan, India. Kavita, 25 years old and the mother of three young children, carries a large brass water jug on her head. She leaves her hut to fetch water for cooking and drinking. She passes by a hand pump which, although it is in working condition, is not her destination. Ten minutes later she arrives at the village nari - a large pond which has collected rainwater - where she sees several women taking water from it. She catches a glimpse of some cows and goats drinking, their legs submerged in the water. She fills her jug with water but does not notice that the water is murky and dirty. After her jug is filled, she stops awhile to chat with her neighbor, and then heads on home."
Page 2 of 9
1.6 WATER SOURCES AND DISTRIBUTION SYSTEMS .....................................................................1 WATER SOURCES..............................................................................................................................................2 SOURCE SELECTION CRITERIA.............................................................................................................................2 TOP RAIN WATER HARVESTING..........................................................................................................................3 LARGE AREA SURFACE WATER HARVESTING........................................................................................................4 SPRINGS...........................................................................................................................................................5 PIPELINE SYSTEMS............................................................................................................................................6 WELLS............................................................................................................................................................7 THE ROPE PUMP...............................................................................................................................................8 RESOURCES......................................................................................................................................................9
Top Rain Water Harvesting
Women and Rainwater Harvesting At Nagercoil, in India, during 1994, a group of women previously engaged by masons as head load carriers were trained in the construction of ferro-cement structures with the objective of ensuring the sustainability of rainwater harvesting systems. Over a 15-day period they learnt to construct doors, roofing sheets and water-retaining ferrocement tanks. This small group of women gained skills in the construction, maintenance and repair of their own rainwater harvesting systems and were subsequently able to find jobs themselves as masons. UNICEF supported training enabled several communities to provide themselves with safe drinking water in addition to enhancing the confidence and status of the women who were trained.
Source: Unicef Technical Guideline Series, A Water Handbook http://www.unicef.org/wes/files/Wat_e.pdf (Apr 05)
Module 1.6 Water Sources and Distribution Systems The following web site contains information on building a rain water harvesting system. Most of the information pertains to North American (Texas) designs and construction but it may be beneficial to you. http://www.twdb.state.tx.us/assistance/conservation/Alternative_Technologies/Rainwater_Harvesting/Rain. htm (Apr 05)
One world has examples of rainwater harvesting programs and links to other resources. http://www.oneworld.net/guides/water/harvesting (Apr 05)
This website is based in India and has a variety of resources, including a run-off calculator (for India only). http://www.rainwaterharvesting.org/ (Apr 05)
Large Area Surface Water Harvesting There are many ways and projects that use surface contouring techniques to collect rain water. The following sketch is one example.
http://www.who.int/water_sanitation_health/hygiene/emergencies/em2002chap7.pdf (Apr 05)
Module 1.6 Water Sources and Distribution Systems This paper discusses the use of rain water harvesting in India. The potential of water harvesting is enormous. With about 5 to10 per cent of India's land area set aside for rainwater collection, most of India's irrigation and household water needs could be met. http://www.iied.org/docs/gatekeep/GK87.pdf (Apr 05)
Springs The following sketches show potential designs for a system that captures the water from an underground spring.
Module 1.6 Water Sources and Distribution Systems
Pipeline Systems Potential negative effects of corroded, leaking water distribution pipelines include the following: 1. Increased risk of contaminating the water supply and causing disease. 2. Increased cost and effort of water treatment. 3. Loss of expensive treated water. 4. Lost revenue for system operators. 5. Higher costs for system users. 6. Water "vulnerability" and shortage. 7. Property damage (for example, sink holes and flooding). 8. Exposure to litigation. http://www.corrosion-club.com/waterpipelines.htm (Apr 05)
"..... what is certain is that cholera was carried by rusty old and leaking water pipes that run through gutters all over the city.......the entire pipe network dates back to World War II........... "
Source: news article "Cholera Surfaces in Bombay" published on www.rediff.com Pipes come in a variety of materials, appropriate for different uses. • Galvanized iron (GI) pipes are used for high-pressure pipeline stretches and for areas where pipes cannot be buried. GI pipes are much more expensive than most other pipes. • Poly vinyl chloride (PVC) pipes are used for lower water pressures, and must be buried as the material deteriorates with prolonged exposure to sunlight and is easily broken by impact. • High density polyethylene (HDPE) pipes are often used as an alternative to GI pipes as they can withstand similar pressures and are less expensive. They are often more appropriate than PVC pipes because they come in rolls which are easier to transport and handle than lengths of PVC pipe, and they do not deteriorate in sunlight. • Bamboo trunks formed into pipes are appropriate only in the following specific situation: in a very isolated area with no road access (making other pipes unavailable or prohibitively expensive), with plenty of bamboo, and for use in a low pressure system (usually gravity spring fed systems). Standpipes must be of sturdy design and include an apron and drain for waste water. As in the case of hand-dug wells and borewells, care should be taken to ensure that the water is drained completely away and that it reaches some ultimate drainage system. In most systems, standard taps are not used as they are easily damaged and tend to be left open, wasting water. "Waste-not" taps are usually employed instead. These taps are of two designs: a spring loaded or a weighted system which ensures that taps cannot be left on. Standpipe and tap design is ultimately less important than the degree of community management and ownership for the success of the system. There are many cases, for example, where standard taps are used successfully on standpipes as the system stakeholders are careful to turn them off, and are able and willing to repair them when necessary.
Module 1.6 Water Sources and Distribution Systems
Wells Wells that obtain water from an underground aquifer usually produce water that has: • • • • • •
High biological quality Constant temperature Limited quantity Often contains minerals which are difficult to remove Dug Shallow wells are inexpensive but easily contaminated and undependable Deeper drilled wells are less contaminated, more dependable but expensive
The following items should be included with all wells: • Well bore lining – to prevent sloughing and surface contamination • Superstructure on the surface – to support the users near the well bore, to support pumps if they are used, and to prevent surface contamination • Run Off Channel – to direct water from the well away from the wellbore, thereby preventing contamination from running back into the well • Cover slab – for the same purpose This web site is from an older couple who work in the tribal areas of India. It has some good articles on how appropriate technology can be used to improve the water supply to rural areas. A hand wheel – bucket pump is described, as well as mini-dams built in small ravines to capture and save water for the dry season. Description of hand and machine dug wells are given. They also describe the importance of community participation http://www.cs.fit.edu/~dclay/art5/TofC.htm (Apr 05)
Module 1.6 Water Sources and Distribution Systems
The Rope Pump The rope pump technology is a solution for water provision used at the family level as well as at the community level, and covering already 25% of the rural population in Nicaragua. The technology was disseminated in a very short time over the whole country and part of Central America with more than 25,000 pumps installed in hand dug wells and drilled wells. It is the national standard pump for the water & sanitation sector. The pumping elements of the rope pump are the pistons and the endless rope, which pull the water to the surface through the pumping pipe made of PVC or plastic. The rotation of the wheel, moved by the handle, pulls the rope and the pistons. The pistons, made of polypropylene or polyethylene injected into molds, are of high precision to prevent hydraulic losses. The structure is basically made out of angle iron, piping and concrete steel. The pulley wheel is made out of the two internal rings cut out of truck tires and joined by staples and spokes, which must be strong for intensive use. A guide box at the bottom of the well leads the rope into the pumping pipe. The guide box is made out of concrete with an internal glazed ceramic piece to prevent any wear. The rope pump can be operated by the whole family and is also used at the community level, for small agriculture production or cattle watering. http://www.ropepump.com/ (Apr 05)
The IDRC has developed a PVC pump that is simple to build and repair. This web site has an article on the pump (as well as other technologies supported by the IDRC). http://web.idrc.ca/en/ev-26970-201-1-DO_TOPIC.html (Apr 05)
There are many other pumps developed by many organizations around the world.
Module 1.6 Water Sources and Distribution Systems
Resources This web site is sponsored by Sunstove Organization. This site is a source for information relating to clean water and solar cooking systems for rural communities worldwide. In underdeveloped countries and other rural communities, the only resources commonly available are natural: sun, gravity, the labor of the people in the community, rudimentary materials native to the area, and the occasional spring for water. Using low-cost systems, people around the world can take crucial steps to dramatically clean their water and food supplies. The "Solar Cooking" section provides in-depth information, drawings, and photographs on how to mass-produce solar cookers by hand, with local materials, purchased with local currency. The "Water Systems" section includes detailed bulletins and diagrams on how to begin collecting and storing clean water. http://www.sungravity.com/index.html
The Hippo Roller - This is a unique method of transporting water, instead of carrying water pails or jugs on your head, why not roll the water home? http://www.hipporoller.org/ (Apr 05)
This web site has good information on water supplies. http://www.who.int/water_sanitation_health/hygiene/emergencies/em2002chap7.pdf (Apr 05)
1.6 1.6 Water Sources and Distribution Systems
Oorani in India – DHAN Foundation
Water can be obtained and distributed from many sources such as rain water harvesting, springs, deep and shallow wells, and surface water. It is suggested that an evaluation be done to select criteria and then choose an appropriate source for water. This module provides an overview of water source systems, storage and distribution.
Module 1.6 Water Sources and Distribution Systems
Water Sources Poverty stricken countries tend to be in the climatic zones most subject to drought and other water problems. The Canadian International Development Agency (CIDA) estimates that there are presently 300 million people living in regions affected by water shortages and that this number will rise to 3 billion by 2025 (CIDA ‘99). Poor countries, with their high rates of population growth, are least able to finance alternative sources of water. Consequently, affordable water treatment which can provide clean water using current water sources could have a huge impact on the lives of millions.
Source Selection Criteria A source for a supply of water is chosen based on several criteria. Frequently there is only one source for a family to access so that is the one they have to use. In other cases, there may be a choice of supplies so the following criteria are used, in some form, to select the source. • Water Quality - How good is it? • Affordability - What does it cost? • Adequacy - Is there enough? • Reliability - How long will it last? • Convenience - How far away? Although groundwater is usually a better option than surface water from a public health engineering standpoint, there is often some resistance by villagers, who have traditionally had a surface water source, to using a new groundwater source. This is most often the case in areas (as in the example below) where the groundwater has a high level of salt, iron or other mineral. But in some cases, people simply prefer the taste of the surface water. (Source: UNICEF WATERfront, Issue 6, pg. 22) Surface Water Tastes Better "It is five PM in the village of Jhadol, Rajasthan, India. Kavita, 25 years old and the mother of three young children, carries a large brass water jug on her head. She leaves her hut to fetch water for cooking and drinking. She passes by a hand pump which, although it is in working condition, is not her destination. Ten minutes later she arrives at the village nari - a large pond which has collected rainwater - where she sees several women taking water from it. She catches a glimpse of some cows and goats drinking, their legs submerged in the water. She fills her jug with water but does not notice that the water is murky and dirty. After her jug is filled, she stops awhile to chat with her neighbor, and then heads on home."
Page 2 of 9
1.6 WATER SOURCES AND DISTRIBUTION SYSTEMS .....................................................................1 WATER SOURCES..............................................................................................................................................2 SOURCE SELECTION CRITERIA.............................................................................................................................2 TOP RAIN WATER HARVESTING..........................................................................................................................3 LARGE AREA SURFACE WATER HARVESTING........................................................................................................4 SPRINGS...........................................................................................................................................................5 PIPELINE SYSTEMS............................................................................................................................................6 WELLS............................................................................................................................................................7 THE ROPE PUMP...............................................................................................................................................8 RESOURCES......................................................................................................................................................9
Top Rain Water Harvesting
Women and Rainwater Harvesting At Nagercoil, in India, during 1994, a group of women previously engaged by masons as head load carriers were trained in the construction of ferro-cement structures with the objective of ensuring the sustainability of rainwater harvesting systems. Over a 15-day period they learnt to construct doors, roofing sheets and water-retaining ferrocement tanks. This small group of women gained skills in the construction, maintenance and repair of their own rainwater harvesting systems and were subsequently able to find jobs themselves as masons. UNICEF supported training enabled several communities to provide themselves with safe drinking water in addition to enhancing the confidence and status of the women who were trained.
Source: Unicef Technical Guideline Series, A Water Handbook http://www.unicef.org/wes/files/Wat_e.pdf (Apr 05)
Module 1.6 Water Sources and Distribution Systems The following web site contains information on building a rain water harvesting system. Most of the information pertains to North American (Texas) designs and construction but it may be beneficial to you. http://www.twdb.state.tx.us/assistance/conservation/Alternative_Technologies/Rainwater_Harvesting/Rain. htm (Apr 05)
One world has examples of rainwater harvesting programs and links to other resources. http://www.oneworld.net/guides/water/harvesting (Apr 05)
This website is based in India and has a variety of resources, including a run-off calculator (for India only). http://www.rainwaterharvesting.org/ (Apr 05)
Large Area Surface Water Harvesting There are many ways and projects that use surface contouring techniques to collect rain water. The following sketch is one example.
http://www.who.int/water_sanitation_health/hygiene/emergencies/em2002chap7.pdf (Apr 05)
Module 1.6 Water Sources and Distribution Systems This paper discusses the use of rain water harvesting in India. The potential of water harvesting is enormous. With about 5 to10 per cent of India's land area set aside for rainwater collection, most of India's irrigation and household water needs could be met. http://www.iied.org/docs/gatekeep/GK87.pdf (Apr 05)
Springs The following sketches show potential designs for a system that captures the water from an underground spring.
Module 1.6 Water Sources and Distribution Systems
Pipeline Systems Potential negative effects of corroded, leaking water distribution pipelines include the following: 1. Increased risk of contaminating the water supply and causing disease. 2. Increased cost and effort of water treatment. 3. Loss of expensive treated water. 4. Lost revenue for system operators. 5. Higher costs for system users. 6. Water "vulnerability" and shortage. 7. Property damage (for example, sink holes and flooding). 8. Exposure to litigation. http://www.corrosion-club.com/waterpipelines.htm (Apr 05)
"..... what is certain is that cholera was carried by rusty old and leaking water pipes that run through gutters all over the city.......the entire pipe network dates back to World War II........... "
Source: news article "Cholera Surfaces in Bombay" published on www.rediff.com Pipes come in a variety of materials, appropriate for different uses. • Galvanized iron (GI) pipes are used for high-pressure pipeline stretches and for areas where pipes cannot be buried. GI pipes are much more expensive than most other pipes. • Poly vinyl chloride (PVC) pipes are used for lower water pressures, and must be buried as the material deteriorates with prolonged exposure to sunlight and is easily broken by impact. • High density polyethylene (HDPE) pipes are often used as an alternative to GI pipes as they can withstand similar pressures and are less expensive. They are often more appropriate than PVC pipes because they come in rolls which are easier to transport and handle than lengths of PVC pipe, and they do not deteriorate in sunlight. • Bamboo trunks formed into pipes are appropriate only in the following specific situation: in a very isolated area with no road access (making other pipes unavailable or prohibitively expensive), with plenty of bamboo, and for use in a low pressure system (usually gravity spring fed systems). Standpipes must be of sturdy design and include an apron and drain for waste water. As in the case of hand-dug wells and borewells, care should be taken to ensure that the water is drained completely away and that it reaches some ultimate drainage system. In most systems, standard taps are not used as they are easily damaged and tend to be left open, wasting water. "Waste-not" taps are usually employed instead. These taps are of two designs: a spring loaded or a weighted system which ensures that taps cannot be left on. Standpipe and tap design is ultimately less important than the degree of community management and ownership for the success of the system. There are many cases, for example, where standard taps are used successfully on standpipes as the system stakeholders are careful to turn them off, and are able and willing to repair them when necessary.
Module 1.6 Water Sources and Distribution Systems
Wells Wells that obtain water from an underground aquifer usually produce water that has: • • • • • •
High biological quality Constant temperature Limited quantity Often contains minerals which are difficult to remove Dug Shallow wells are inexpensive but easily contaminated and undependable Deeper drilled wells are less contaminated, more dependable but expensive
The following items should be included with all wells: • Well bore lining – to prevent sloughing and surface contamination • Superstructure on the surface – to support the users near the well bore, to support pumps if they are used, and to prevent surface contamination • Run Off Channel – to direct water from the well away from the wellbore, thereby preventing contamination from running back into the well • Cover slab – for the same purpose This web site is from an older couple who work in the tribal areas of India. It has some good articles on how appropriate technology can be used to improve the water supply to rural areas. A hand wheel – bucket pump is described, as well as mini-dams built in small ravines to capture and save water for the dry season. Description of hand and machine dug wells are given. They also describe the importance of community participation http://www.cs.fit.edu/~dclay/art5/TofC.htm (Apr 05)
Module 1.6 Water Sources and Distribution Systems
The Rope Pump The rope pump technology is a solution for water provision used at the family level as well as at the community level, and covering already 25% of the rural population in Nicaragua. The technology was disseminated in a very short time over the whole country and part of Central America with more than 25,000 pumps installed in hand dug wells and drilled wells. It is the national standard pump for the water & sanitation sector. The pumping elements of the rope pump are the pistons and the endless rope, which pull the water to the surface through the pumping pipe made of PVC or plastic. The rotation of the wheel, moved by the handle, pulls the rope and the pistons. The pistons, made of polypropylene or polyethylene injected into molds, are of high precision to prevent hydraulic losses. The structure is basically made out of angle iron, piping and concrete steel. The pulley wheel is made out of the two internal rings cut out of truck tires and joined by staples and spokes, which must be strong for intensive use. A guide box at the bottom of the well leads the rope into the pumping pipe. The guide box is made out of concrete with an internal glazed ceramic piece to prevent any wear. The rope pump can be operated by the whole family and is also used at the community level, for small agriculture production or cattle watering. http://www.ropepump.com/ (Apr 05)
The IDRC has developed a PVC pump that is simple to build and repair. This web site has an article on the pump (as well as other technologies supported by the IDRC). http://web.idrc.ca/en/ev-26970-201-1-DO_TOPIC.html (Apr 05)
There are many other pumps developed by many organizations around the world.
Module 1.6 Water Sources and Distribution Systems
Resources This web site is sponsored by Sunstove Organization. This site is a source for information relating to clean water and solar cooking systems for rural communities worldwide. In underdeveloped countries and other rural communities, the only resources commonly available are natural: sun, gravity, the labor of the people in the community, rudimentary materials native to the area, and the occasional spring for water. Using low-cost systems, people around the world can take crucial steps to dramatically clean their water and food supplies. The "Solar Cooking" section provides in-depth information, drawings, and photographs on how to mass-produce solar cookers by hand, with local materials, purchased with local currency. The "Water Systems" section includes detailed bulletins and diagrams on how to begin collecting and storing clean water. http://www.sungravity.com/index.html
The Hippo Roller - This is a unique method of transporting water, instead of carrying water pails or jugs on your head, why not roll the water home? http://www.hipporoller.org/ (Apr 05)
This web site has good information on water supplies. http://www.who.int/water_sanitation_health/hygiene/emergencies/em2002chap7.pdf (Apr 05)
