In the author's words, the books seeks 'to serve as a one-stop source for every aspect of water and its management that city and town dwellers would benefit from knowing and utilising.' Charming cartoons both illustrate the author's main points and add to the pleasure of reading this book.
Introduction
Every one of us, would love to have ready access to good quality water in adequate quantity to meet our daily needs. Paradoxically, in spite of all the technological progress the country has made in the many decades since independence, ready access to good water for our daily needs is yet to become a reality in most of our cities, towns as well as villages. In thousands of villages, women still have to walk long distances daily to collect potable water. In cities and towns, groundwater levels are falling and potable water is increasingly being purchased.
While the powers that be have taken various steps in these 57 years, their impact at the individual household level has been none too encouraging. Therefore it is important that we citizens should strive, in our own selfish interest, to alter this sad state of affairs. And we can make a difference if only we put in efforts at the micro level - at the individual level, at the household level, at the neighbourhood level and at the community level - to reduce our dependence for water on external sources.
The tremendous advantage in acting at the micro-level is that we have the maximum control and influence on any activity undertaken by ourselves and we can therefore be that much surer of achieving results and reaping benefits of our efforts.
Three steps to self-reliance in water
And what are these efforts that can confer on us - town and city dwellers - that vital self-reliance in our daily water needs ? In essence, they are three fold:
1. Harvesting rainwater
Unlike many other areas in the world, our country is very fortunate in that it receives substantial rainfall from its two monsoons. If only this rainfall is tapped, can it meet fully our most essential daily need, i.e. water for our cooking and drinking needs, in every town and city - even in areas where the annual rainfall in scanty.
And what is more, it can meet from 20% to 100% of the total water needs of practically all towns and cities, depending on the rainfall in that place and its population.i.e. tapping rainwater wherever and whenever it falls, and diverting it to an appropriate storage for our use later.
2. Purifying used water and putting it back for reuse
The water that we use for bathing, washing of clothes and cleaning the floors constitutes 50-60% of our total daily water usage. If only we clean this slightly contaminated water used for these purposes, it becomes available for fresh use again.
3. Conserving the water available for our daily use
Knowingly or unknowingly, we use water wastefully in our daily activities. Conservation of water is nothing but realising the value of water and adopting simple techniques of using available water more efficiently for various uses in daily life, so that what is available can meet our needs for a much longer period. Its benefits would become obvious instantly to those who are facing acute water shortages.
Together these three methods, are guaranteed to make citizens of every town and city self-reliant at least in their minimal water needs, if not their entire needs. And all three can be done at the micro-level without much expenditure or effort.
Reliable and ready information based on practical experience
This book seeks to provide both from the author's first-hand experience in all the above fields, over more than two decades. The language used is simple and jargon is avoided, so that all readers can understand and beneficially utilise the information and guidance provided.
Rainwater harvesting in urban areas has come into vogue only recently and among them, it was in Chennai that meaningful activity could be considered to have first commenced. The technology involved in it, although simple in nature, is still evolving.
The techniques detailed in this book abour rainwater harvesting represent the results of pioneering activity of the author in more than 200 apartment complexes in Chennai, comprising over 4000 apartments.
As for recycling of used water, the methods available till recently had been mainly chemical, requiring fairly large investments and regular maintenance efforts that are not convenient for operations in domestic environments. But alternate methods that are economic and user friendly were not so far available to city and town dwellers.
For the first time, a method is presented in this book, which is simple, easy to operate and maintain, and also eco-friendly. The method is the outcome of the author's efforts to meet the challenge of acute water shortages in manyof the apartment complexes, he was involved with in Chennai.
Efficient storage and distribution of water of various qualities available in any premises has an important role in the route to self-reliance. The guidance on this as also on conservation of water are both derived from actual experience on the field.
Frequently-asked questions
- How do you locate the right spot in your premises to dig a bore well?
- How can you influence its construction so that you can charge it with rainwater efficiently ?
- What is potable water?
- Is mineral water the same as bottled water?
- How does one decide that the water available during travelling is safe for drinking ?
- What can one do if the water from one's well or borewell becomes yellow on storage and soils clothes washed in it ?
- How can one tackle the problem of water stagnating on the road in front of one's home after the rains and in the process get more water for one's own use ?
- If your town does not have a sewerage system, how do you dispose off your sewage hygienically without contaminating your water sources ?
- What is desalination ?
- How relevant is reverse osmosis to you ?
- What does sweet water in sandy coastal areas turn saline ?
All these and many other such questions that city and town dwellers have to grapple with, are answered in simple language.
Water and soil inter-relationship
Water and soil are intimately related, as it is the soil of Mother Earth, that ulimately stores teh water we need for our use and influences its quality. Therefore, the soil-water inter-relationship and the means of locating water sources below the ground are briefly presented.
Tackling urban floods
Ironically, even while water is in short supply in our towns and cities, our streets invariably get flooded during the monsoon rains and our daily life is disrupted in many ways. And this happens in spite of the existence in many cases of a storm water drainage system.
Some ideas have therefore been offered on how individuals and communities can tackle this problem with rich benefits not only in rendering streets water free but also in the process can get more water for their use. Some suggestions have also been added on what can be done, at the macro level with only moderate outlays to mitigate the problem.
Sewerage systems
The sewerage system wherever it exists, was originally intendended to carry human faecal matter to treatment plans for hygienic dispoal. The system actually operates very inefficiently and is not only causing acute degradation of our precious waterways all over the country, but is actually the primary cause for the shortage of water experienced by our towns and cities as it carried away all the used water from them.
In places that do no have a sewerage system, contamination of good water at shallow depths by the outflow from septic tanks is becoming a major problem. Both these warrant urgent and serious attention at both the individual and governmental levels. The book not only offers some thoughts on corrective measures at the macro level but also concrete steps that individuals can take at the micro level to deal with the problem and have greater access to usable water.
One-stop source on every aspect of water management for city and town dwellers
In short, the book seeks to serve as a one-stop source for every aspect of water and its management that city and town dwellers would benefit from knowing and utlising. It is the author's belief that the information and experience shared in this book can be beneficially utilised by residents of most towns and cities of India. The water management techniques presented in this book are all economical and derived from first hand experience.
Architects and builders should incorporate water management plans in their designs
Hopefully, architects will incorporate these techniques at the outset itself in their building designs so that builders will readily install them in the homes and colonies they construct and make life that much more comfortable and happier for those who will live in them.
It is important to note that the techniques described in this book can be applied even in buildings that have already been constructed. The outlay needed to introduce rainwater harvesting systems or water recycling systems in buildins already constructed is likely to be more than what would have been enough if they had been been incorporated during their original construction. But the resultant benefits would fully justify the expenditure.
Sustainable urban water cycle
If you and I are experiencing water shortages today, it is because we have not valued water and used it in an organised manner. All the water that we use and all the rainwater that falls on our homes and gardens is moving laterally away from our homes and cities, first into water bodies polluted by us and then into the sea. The situation will alter dramatically if only we make it move cyclically, as we can see it in the chart below.
"Is it practicable ?", you may ask.
Yes it is !
Chapter 1: Water - In the past, present and future
This chapter takes a look at water management through the decades. It also presents the state of urban water bodies and the impact of sewerage as it exists today.
1. Urbanisation and water
For the last five decades, India has been shifing away from its predominantly rural nature and it is predicted that 60% of our population will be living in urban areas in the year 2015. However, infrastructure has not been able to meet this growth. This failure on the part of the governmental authorities should not prevent individuals from seeking solutions and making efforts to ensure access to water and its safe disposal.
2. Rain - The ultimate source of water
India receives about 110 cm of rain per unit area, against the global average of 80 cm. The distribution of this rainfall throughout the country is discussed.
3. Harvesting the rain - Our traditional wisdom
The excellent traditional systems of rainwater harvesting, especially as practised in Rajasthan are described, as are the tanks in south India. The current neglect of these systems leads to water scarcity in the dry season and floods in the monsoons.
Our urban waterbodies such as Puttenahalli lake pictured here are dying due to neglect
4. Water cycle in the 'good old days'
Before the preponderance of high-rise buildings, houses had a connection with the world outside. Water used in the kitchen, bath and septic tank would be purified as it percolated through the soil and ultimately reach the open well.
This cycle was broken with the advent of town sewerage when effluent from the toilets would directly go into the sewerage system and out of the vicinity. This not only reduced the water available for recharge, but also polluted available water sources.
5. The degradation and disappearance of water bodies
Historical tanks in our urban areas are being encroached upon while the rivers are being polluted.
Chapter 2: The language of water management
The various terms used in the book are explained here in a clear and simple manner.
Chapter 3: The first step in self-reliance: Rainwater harvesting
This chapter begins with discussing the prevalence of water conflicts despite adequate rainfall. The hydrological cycle is also discussed, as are ways and means of measuring rainfall. Simple calculations illustrate the magnitude of water we receive as rain.
A table lists the potential per capita amount of water available as rainwater. While these are ballpark figures, they inspire one to make some effort at harvesting atleast a fraction of this water. The role of soil as a store for water is also explained.
The tremendous amount of water received by rainfall can, if harvested, make us self-reliant in water (Source: Lij Jinaraj, Wikimedia Commons)
Chapter 4: Soil water inter-relationship
This chapter leads off from the earlier one and explains the various types of soil and their interaction with water. The relationship between subsoil profiles and well depths is illustrated.
Chapter 5: Frequently asked questions on rainwater harvesting
The author states that there are three questions invariably raised by people when rainwater harvesting is discussed. These three questions are answered in the chapter:
- Why should I harvest rainwater and put it into the soil when my neighbour is going to conveniently pump it out for his use?
- If we put so much water into the soil around the building, will it not weaken the foundation of the building?
- The area around my house is unpaved and so the rainwater will anyway be absorbed by the soil. Why should I waste money to put up a rainwater harvesting system?
Chapter 6: Designing a rainwater harvesting system
All rainwater harvesting systems (RWH) have a basic principle: 'Catch rainwater wherever and whenever it falls and divert it into an appropriate storage for later use'. However, each system needs to be tailored to its specific site.
The three components of a rainwater harvesting system are catchment area, storage unit, and conveyance mechanism. The factors influencing design are:
- Average annual rainfall and catchment area
- Distribution of rainfall over the year
- Intensity of rainfall
- Daily consumption rate
- Runoff coefficient
- Availability of piped water supply
- Quality of the ground water available
- Sub-soil profile and depth of water table
- Financial constraints
Chapter 7: Rainwater harvesting systems to suit your need
The details of different types of rainwater harvesting systems to suit different situations and needs are presented in this chapter. These are classified as follows:
Rooftop RWH
- Storing rooftop rainwater in tanks above ground and in underground sumps
- Storing rooftop rainwater in the subsoil or through a well
Harvesting the surface runoff
- An independent house with space around it largely or fully unpaved
- Houses and apartment complexes where open spaces are largely paved
- Rainwater harvesting in row housing or in continuous housing areas
This chapter explains in detail the several components of rainwater harvesting such as filters, first-flush systems, gate trenches, and pipes in great detail, so as to enable a lay person to design and install his/her own rainwater harvesting system.
Chapter 8: Beneficial effects of rainwater harvesting
This chapter starts off by assuring the reader that while the benefits of rainwater harvesting might seem slow, they are definitely sure. The quantitative and qualitative benefits of rainwater harvesting in terms of increased output from wells and improvement of brackish or hard water are illustrated through case studies.
Other benefits to efficiency of use of electricity, quality of soil, and free alternatives to defluoridation plants are explained.
Chapter 9: Misconceptions about rainwater harvesting
The following common misconceptions are clarified in this chapter:
- Leaves from the trees near the terrace will go into the wells or storage sumps
- Dust from the terrace will go into the well along with the rainwater
- People may urinate on the terrace and this will mix with the rainwater going into the well or sump
- Bird droppings will contaminate the rainwater
- The rainwater may carry with it dead rats or dead lizards
- What if fire crackers are lit on the terrace on occasions like Diwali?
- If rainwater is allowed to flow directly into the well, the springs supplying the well will be choked leading to the well going dry
- Harmful chemical pollutants may be present in the rainwater harvested
Chapter 10: Maintenance of the rainwater harvesting system
This brief chapter lists tasks that need to be performed annually to maintain the efficiency and longevity of the rainwater system.
Chapter 11: The second step in self-reliance – Used water reuse
This chapter explains that it is both possible and desirous to purify and reuse the water used for bathing and washing of clothes. To make this possible, it is necessary to separate the outflow of sewage (black water), kitchen outflow and bath water (grey water). The wastage involved in the present method of sewage disposal is convincingly explained. Alternatives to this wastage in the form of dry compost toilets are explained.
Chapter 12: Used water recovery and reuse - How ?
A simple process of treating wastewater using soil and canna and other plants is described in detail including the process, installation and maintenance. Integrating rainwater harvesting and grey water treatment systems are also explained.
Canna growing as part of a wastewater treatment system in Bhuj
Chapter 13: Using water of different qualities advantageously
Just as it is advantageous to segregate water after use, it is also beneficial to segregate water before use. Various uses require water of different qualities. It is wasteful, for example, to use potable-quality water for flushing. Seven daily needs of water are considered and methods of conserving water use in each case are suggested.
Chapter 14: Distribution of water in housing complexes
This chapter describes the design of a versatile three–compartment overhead tank which can store and distribute one, two or three different qualities of water. Builders normally provide a two-compartment overhead tank (OHT) tank where one compartment stores potable water and the other non-potable water. When more than one borewell or dug well is tapped, often one may yield water of better quality than the other. In a two-compartment OHT, these two qualities get necessarily mixed. If therefore, a three compartment OHT is provided, these two qualities need not be mixed and the better quality can be used for bathing and clothes washing.
The author has given the design for a three-compartment OHT using the same space which enables these two qualities to be stored separately and used. This model also enables the use of water treated and recovered from used grey water to be exclusively used for flushing and gardening.
Chapter 15: The last step in total self-reliance: Water conservation
Unusually for books on rainwater harvesting, this book also takes the laudable step of discussing demand management. Crucially, this chapter debunks the commonly believed myth that stored water gets spoiled. Means of reducing the water wasted by flushing, bathing, washing machines, wash basin, washing of vessels, irrigation of the garden, cleaning vehicles, leaking taps and shower heads, are listed.
Chapter 16: Locating underground water sources
Water divining, using natural indicators such as those laid out by Varahamihira, using soil data are the various means used to locate underground water. The procedures best followed for locating the site for a good dug well and borewell are explained in detail.
Chapter 17: Storm water drainage - a costly way to waste water?
Stormwater drainage systems as designed today take water away from the locality and drain it into a far-off water body. However individual rainwater harvesting systems, and those at the community level will recharge the water table in the neighbourhood and make the residents self-reliant.
Stepwells such as this one in Mulbagal store rainwater runoff (Image courtesy: Manjunath Prasad)
Chapter 18: Sewage disposal - A mega way to spoil water !
The water-borne system of sewage disposal is the main reason for the water shortages faced by urban areas today. At the same time, the disposal of this sewage consumes money and pollutes out water bodies. Ways in which this loss can be mitigated using simple actions at the micro and macro level are explained.
Ecosan toilets, like the model shown above, provide a safe, clean and effective alternative to conventional flush toilets (Photo courtest: Vishwanath S)
Chapter 19: Potable water and quality standards
The various factors affecting the potability of water, and available standards that define potable water are presented in this chapter. Methods of disinfecting and sterilisation of drinking water and the disinfection of a contaminated well are explained. The advantages of storing water in traditional containers such as earthen pots, silver mugs and copper jugs ae discussed.
Chapter 20: Iron salts: The 'mosquitoes in water and their removal
Iron salts are likened too mosquitoes in this chapter due to their ability to distress us even when present in minute quantities. Methods of converting the soluble ferrous salts into insoluble ferric salts which can then be filtered out are discussed. The beneficial impact of rainwater harvesting as it dilutes the salts in the aquifer is discussed. The various factors to be considered before installing iron removal units such as a reliable analysis of the iron content.
The red stains around this Chapakal at Khagaria, Bihar are indicative of iron contamination
Chapter 21: Desalination, reverse osmosis and distillation
The three water-purification processes listed above are detailed in this chapter. It explains that rainwater harvesting, grey water recycling, and water conservation are more sustainable as they require very low outlays.
Chapter 22: Water and builders
Construction activities consume very large quantities of water. The quality of water required for construction is presented. Initial investigation to be done regarding water sources and water availability in the neighbourhood is explained, as well as the means to ensure adequate water supply during the construction process. The desirability and means of including rainwater harvesting and grey water recycling in the initial design is explained.
Appendix 1: Coastal residents, beware of seawater intrusion !
The mechanics of seawater intrusion into groundwater are explained using Chennai as a case study.
Appendix 2: The water poisoners: Arsenic and fluoride
Arsenic and fluoride are two life-threatening contaminants that are present in certain parts of India. An overview of this contamination is presented along with means of mitigation.
Appendix 3: Monsoon: The awesome 'Mausem'
The south-west and north-east monsoons, their origin and impact, are detailed in this chapter.
Appendix 4: Rainfall and rainy days in select towns and cities
This presents the average rainfall data in the form of total rainfall (in mm) and the number of rainy days for 88 towns and cities for the period 1951-1980.
Appendix 5: Construction of a rain gauge
Constructing and operating a simple rain guage can be an interesting and informative endeavour for the individual. This chapter explains the means of doing this.
Appendix 6: How Janaki stopped going down the hill to fetch water
The inspiring story of Janaki of Kepulakodi village, who used her old saree to harvest rainwater, is narrated in this chapter.
Appendix 7: Varamihira's natural indicators for water sources
1500 years ago, Varahamihira in his 'Brihad Samhita' listed methods of detecting underground water sources, accessing water in rocky soils, and flood prevention. These indicators of determining underground water are listed in this chapter.
Appendix 8: Turning waste into wealth: The terrace garden
Terrace gardens dispose of kitchen waste, constructively use waste water, and provide fresh vegetables for the kitchen. The method of achieving this is explained.
Appendix 9: Efficient water managers in nature
This chapter presents plants that grow in adverse conditions by efficiently storing and using any available water.
About the author
Indukanth Ragade holds a Ph.D. in organic chemistry from the Presidency College, University of Madras (1963) and was a post-doctoral fellow in the Universities of Illinois and South Carolina from 1964 to 1967. He worked with M/s Atic Industries Ltd, manufacturers of synthetic dyestuffs in Gujarat from 1968 to 1984.
Since 1984, he has been with M/s Alacrity Foundations (P) Ltd, Chennai, an organisation reputed for its construction of quality apartment complexes and good corporate practices.
A keen urban environmentalist and a passionate believer in sustainable development, he has, over the past two decades, pioneered the practice of eco-friendly methods practicable in the urban environment for water management. In recent years, he has been involved in the development of simple methods of managing domestic waste and has also developed a re-engineered proto-type of a solar water heater that can be made available at a low cost.
The author can be contacted at isragade@yahoo.com or +91 7358-646986