Title of the Project -RAINWATER HARVESTING PDF

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Title of the Project - RAINWATER HARVESTING Submitted by Name of the Candidate - PAPIA SAMANTA C.U. Registration No. - 134-1211-0441-17 Roll No. – 171134-12-0026 Class - B.COM 6TH SMESTER (GENERAL) College Roll No. - 4125 Supervisor’s Certificate This is to certify that Ms. PAPIA SAMANTA a student o...

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Title of the Project - RAINWATER HARVESTING

Submitted by Name of the Candidate - PAPIA SAMANTA C.U. Registration No. - 134-1211-0441-17 Roll No.

–

171134-12-0026

Class - B.COM 6TH SMESTER (GENERAL) College Roll No.

- 4125

Supervisor’s Certificate

This is to certify that Ms. PAPIA SAMANTA a student of B.Com 6th Semester (General) of Victoria Institution (College) under the University of Calcutta has worked under my Supervision and guidance for her Environment Studies Project Work and prepared a Project Report with the title RAINWATER HARVESTING which she is submitting, is her

Genuine and original work to the best of my knowledge.

Signature of the Teacher : Name of the Teacher : Date :

Signature of Principal

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Student’s Declaration

I hereby declare that the Environment Studies Project Work with the title RAINWATER HARVESTING submitted by me for the partial fulfilment of the degree of B.COM. 6th Semester (General) under the University of Calcutta is my original work and Has not been submitted earlier to any other University / Institution for the fulfilment of the Requirement for any course of study.

Signature of the Student: Name of the Student : PAPIA SAMANTA C.U Registration No. : 134-1211-0441-17 Place: Kolkata Date: 25/06/2020

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Acknowledgement I am thankful to all Respected Professors and Teachers for advice and computation, with their guidance and Supervision,and very thanks to ineternet networking which I have been able to complete this project. The project taught me a lot about Rainwater Harvesting and ways to preserve it. I am thankful to my Professor Mr. Amit Kumar Das for giving me this topic.

I have been able to lean a lot about it. Acknowledgement. In preparation of my assignment, I had to take the help and guidance Of some respected persons, who deserve my deepest gratitude, as the completion of This assignment gave me much pleasure, I would like to show my gratitude Mr. Amit Kumar Das sir. I would like to express my special thanks of gratitude to my teacher (AKD Sir) as well as our principal who gave me the golden opportunity to do this Wonderful project on the topic (RAINWATER HARVESTING), which also helped me In doing a lot of Research and i came to know about so many...

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A PROJECT OF

RAINWATER HARVESTING 2019 – 2020

Submitted by:

PAPIA SAMANTA College Roll No. - 4125 College Name - VICTORIA INSTITUTION [COLLEGE] B.COM [GENERAL] C.U. Registration No. - 134-1211-0441-17,

Roll No. – 171134120026

Subject - ENVIRONMENTAL STUDIES [AECC 6.1 Chg.] (EVS)

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CONTENTS:1. INTRODUCTION (Mainly Concept of Rainwater Harvesting) 2. HISTORY OF RAINWATER HARVESTING IN INDIA.

3. OBJECTIVES OF RAINWATER HARVESTING. 4. DIFFERENT METHODE/PROCESSES OF RAINWATER HARVESTING. 5. SUPPLYING DRINKING WATER IN RURAL AREA (GREEN SOURCES)

6. ADVANTAGES OF RAINWATER HARVESTING. 7. DISADVANTAGES OF RAINWATER HARVESTING.

8. CONCLUSION. 9. BIBLIOGRAPHY.

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1. INTRODUCTION:In India, rainwater harvesting has been in practice for more than 4000 years. It is basically a simple process of accumulating and storing of rainwater. Rainwater harvesting systems, since ancient times, has been applied as a Supply for drinking water, water for irrigation, and water for livestock. Rainwater harvesting (RWH) is the collection and storage of rain, rather than Allowing it to run off. Rainwater is collected from a roof-like surface and Redirected to a tank, cistern, deep pit (well, shaft, or borehole), aquifer or A reservoir with percolation. The Inventor of KFP Patented RWH Technology But his heart was more in growing into the soil than building on it, he gave up his Thriving business for agriculture. In year 1990, Vijay Kedia started horticulture in 8 Hectare farm near Aurangabad. Water stood in front of him as a major challenge. Millions of people throughtout the world do not have access to dean water for domestic purposes. In many parts of the world conventional piped water is either absent, unreliable or too expensive. One of the biggest challenges of the 21st century is to overcome the growing water shortage. Rainwater harvesting (RWH) has thus regained its importance as a valuable alternative or supplementary water resource, along with more conventional water supply technologies. Much actual or potential water shortages can be relived if rainwater

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 Rainwater harvesting is manmade way to collect and store the rainwater and use it when needed. Mostly water is collected from hard surfaces like rooftop and other raised solid surfaces. g. Sometime rainwater is stored in manmade pits and used for onsite water supply or to recharge ground water. Government of India has decided to make Rainwater harvesting compulsory in urban areas considering increasing population and burden on water supply. Low rainfall situations and drying ground water levels are main challenges in urban as well as rural areas to keep sufficient water supply. Rain water harvesting is sustainable way of water conservation. Such water can be used throughout the year for all basic needs after filtration and UV disinfection. Check out this article to know.

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Some facts about rainwater harvesting in India India is practicing rainwater harvesting since 10th century. In 11th century, largest rainwater harvesting tank was created by Chola kings and it is 16 kilometer long. Average roof collects 600 gallons (2,271.2 L) of water for every inch of rainfall It needs minimal infrastructural changes to start rainwater harvesting. Filtration system and UV disinfection is needed to use this water for drinking. Simple ways of rainwater harvesting  Simple roof water collection system, a pump and a storage tank makes basic rainwater harvesting system. is needed to circulate water between filter, storage tank and house. UV disinfection systems like those offered by ALFAA UV are needed to destroy micro-organisms to make water safe for drinking.

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2. HISTORY OF RAINWATER HARVESTING IN INDIA Many rainwater harvesting roots can be traced back to India. Including systems that are built on top of homes which are still used to this day. ... Ancient India also developed technology such as large reservoirs to hold rainwater and dams to divert and capture rainwater. India is practicing rainwater harvesting since 10th century. In 11th century, largest rainwater harvesting tank was created by Chola kings and it is 16 kilometer long. It needs minimal infrastructural changes to start rainwater harvesting. The Need of Water: Why collect rainwater? Civilizations, settlements, countries, and empires of the past had basic needs to survive just like we do in the present day. Water, food, and shelter were a continuous struggle to provide, especially in dry climates where water was scarce. But there was a solution and people of the past came up with brilliant methods of solving these issues. One idea that became a sustaining source throughout thousands of years was rainwater collection and diversion.

ORIGIN OF RAINWATER HARVESTING Obviously, it is nearly impossible to trace back to which civilization used the method of Rainwater harvesting first, but evidence shows that different types of rainwater collection Systems were used in 2000 BC in India, Mesopotamia, China, and modern day Israel. The basic design of these systems often involved a large rock formed into a basin using clay And other rocks to seal it from leaking. And then, using different diversion tactics, water would Be stored and used for drinking, washing, agriculture and more.

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INDIA:Many rainwater harvesting roots can be traced back to India. Including systems that are built on top of homes which are still used to this day. In fact, when I visited India in 2017, I saw many homes with aspects of these systems used. Ancient India also developed technology such as large reservoirs to hold rainwater and dams to divert and capture rainwater.

RAINWATER HARVESTING SETTLES DOWN There began to be issues with the historic way of collecting rain. As civilizations grew, the cisterns would become more and more contaminated. This lead to the spreading of diseases since the modern technology was not available to remove bacteria. As countries became more developed, centralized water utilities began to sprout and became the primary source for all water needs. RAINWATER HARVESTING IN THE MODERN AGE AND WHY IT’S COMING BACK The age of rainwater harvesting has not reached its peak. Many farms continued to use rainwater cisterns for feeding livestock. And as technology developed in water treatment abilities, people started to use rainwater in their homes as the primary source of water yet again. But why is rainwater harvesting starting to come back? For the most part, development brings advantages, but there has been a side effect of increasing development that is depleting our natural underground water supply. In the water cycle, there is a critical step that must occur for the process to be effective – groundwater recharge. Through the construction of roadways, cities, and increasing population in metro areas, water is being used, but no water is being replenished. Storm water is collected and sent into rivers and out to the ocean. Large amounts of water needs to reach the earth and be absorbed in the ground to replenish the natural underground aqueducts. And because this is not happening, water sources are drying up.

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3. OBJECTIVES OF RAINWATER HARVESTING:The main objectives of rainwater harvesting are It means capturing rain where it falls or capturing the runoff in your own village or town. And taking measures to keep that water clean by not allowing polluting activities to take place in the catchment. Reducing loss of water by its running –off. It is a technique of increasing the recharge of groundwater by storing rainwater locally, through roof water harvesting, refilling of dug wells, recharging of hand pumps, construction of percolation pits, trenches around fields and bunds or dams on small rivulets. The main Objectives of rainwater harvesting are: 1. To meet the increasing demand of water. 2. To reduce the run-off which chokes the drains? ADVERTISEMENTS: 3. To avoid the flooding of roads. 4. To raise the underground water table. 5. To reduce groundwater pollution. 6. To reduce soils erosion. 7. Supplement domestic water needs.

The main objectives of rainwater harvesting are:     

To meet the increasing demand of water. To reduce the run-off which chokes the drain. To raise the underground water table. To reduce groundwater pollution etc.

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In ancient India, there was a tradition of developing a rainwater harvesting system. People knew the rainfall regimes. Rooftop rainwater harvesting was practiced to store drinking water, particularly in Rajasthan. In Bikaner and Barmer regions most of the houses have underground tanks or tankas, for storing drinking water. The tankas were built inside the house or in the courtyard. These are connected to the sloping roofs of the houses with a pipe. The first spell of rain is used for cleaning the roofs and the pipes. The rain water thus collected is considered as the purest form of water. It is an extremely reliable source of drinking water. Nowadays, in western Rajasthan, the practice of rooftop rainwater harvesting is on the decline as plenty of water is readily available from the perennial Indira Gandhi Canal. In ancient India, hydraulic structures were constructed to store water for irrigation and domestic use. During the time of Chandragupta Maurya; dams, lakes and irrigation system were extensively built. In the I Ith century, Bhopal lake, one of the largest artificial lakes of its time was built. In the 14th century, the tank in Hauz Khas, Delhi was constructed by lltutmish for supplying water to Siri Fort area. In arid regions, the agriculture fields are used to store water which can moisten the soil, like ‘khadins’ in Jaisalmer and ‘Johads’ in other parts of Rajasthan. Tamil Nadu is the first and the only state in India which has made rooftop rainwater harvesting structures compulsory to all the houses across the state.

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4. DIFFERENT METHODES / PROCESSES OF RAINWATER HARVESTING:

Surface Runoff Harvesting. In urban areas, rainwater flows away as surface runoff. This

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Runoff can be caught and used for recharging aquifers by adopting appropriate methods. ...

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Rooftop Rainwater Harvesting. It is a system of catching rainwater where it falls.

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Broadly there are two ways of harvesting rainwater, namely; surface runoff

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Harvesting and rooftop rainwater harvesting. Rainwater harvesting is the collection

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And storage of rain for reuse on-site, rather than allowing it to run off. The stored

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Water is used for various purposes, such as gardening, irrigation, etc. This article

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discusses multiple methods of rainwater harvesting

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(i)

Roof Top Rainwater Harvesting through Recharge Pit:

(ii)

Roof Top Rain Water Harvesting through Recharge Trench:

(iii)

Roof Top Rain Water Harvesting through Existing Tube wells

(iv)

Roof Top Rain Water Harvesting through Trench with Recharge Well:

(v)

Rain water harvesting through Check Dams/Cement Plugs/Nala Bunds:

(vi)

Rain Water Harvesting through Recharge Shaft:

(vii)

Rain Water Harvesting through Dug well Recharge:

(viii) Ground Water Dams or Sub-surface Dykes:

METHODES/ PROCESSES

1. SURFACE RUNOFF HARVESTING

2. ROOFTOP RAINWATER HARVESTING

COMPONENTS OF THE ROOFTOP RAINWATER HARVESTING:THE ILLUSTRATIVE DESIGN OF THE ESSENTIAL COMPONENTS OF THE ROOFTOP RAINWATER HARVESTING SYSTEM IS GIVEN IN THE TYPICAL SCHEMATIC DIAGRAM SHOWN IN FIG 1. THE SYSTEM MAINLY CONSTITUTES OF FOLLOWING SUB-COMPONENTS:

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FIG 1: COMPONENTS OF RAINWATER HARVESTING 1. CATCHMENT The surface that receives rainfall directly is the catchment of rainwater harvesting system. It may be a terrace, courtyard, or paved or unpaved open ground. The terrace may be a flat RCC/stone roof or sloping roof. Therefore the catchment is the area, which actually contributes rainwater to the harvesting system.

2. TRANSPORTATION:Rainwater from the rooftop should be carried through down to take water pipes or drains to the storage/harvesting system. Water pipes should be UV resistant (ISI HDPE/PVC pipes) of the required capacity. Water from sloping roofs could be caught through gutters and down take the pipe. At terraces, the mouth of each drain should have wire mesh to restrict floating material.

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3. FIRST FLUSH:The first flush is a device used to flush off the water received in the first shower. The first shower of rains needs to be flushed-off to avoid contaminating storable/rechargeable water by the probable contaminants of the atmosphere and the catchment roof. It will also help in cleaning of silt and other material deposited on the roof during dry seasons. Provisions of first rain separators should be made at the outlet of each drainpipe.

4. FILTER:There is always some skepticism regarding Roof Top Rainwater harvesting since doubts are raised that rainwater may contaminate groundwater. There is a remote possibility of this fear coming true if the proper filter mechanism is not adopted. Secondly, all care must be taken to see that underground sewer drains are not punctured, and no leakage is taking place in close vicinity. Filters are used for the treatment of water to effectively remove turbidity, color, and microorganisms. After the first flushing of rainfall, water should pass through filters.

There are different types of filters in practice, but the basic function is to purify water. Different types of filters are described in the following section: 16

1. Sand Gravel Filter These are commonly used filters, constructed by brick masonry and filleted by pebbles, gravel, and sand. Each layer should be separated by wire mesh. 2. Charcoal Filter Charcoal filters can be made in-situ or in a drum. Pebbles, gravel, sand, and charcoal as shown in the figure should fill the drum or chamber. Each layer should be separated by wire mesh. The thin layer of charcoal is used to absorb odor if any. 3. PVC –Pipe filter This filter can be made by PVC pipe of 1 to 1.20 m length; Diameter of pipe depends on the area of roof. Six inches dia. pipe is enough for a 1500 Sq. Ft. roof and 8 inches dia. pipe should be used for roofs more than 1500 Sq. Ft. Pipe is divided into three compartments by wire mesh. Each component should be filled with gravel and sand alternatively as shown in the figure. A layer of charcoal could also be inserted between two layers. Both ends of the filter should have a reduction of the required size to connect the inlet and outlet. This filter could be placed horizontally or vertically in the system. A schematic pipe filter is shown in Fig 3

Fig 3: PVC-Pipe filter

Fig 4: Sponge Filter

4. Sponge Filter It is a simple filter made from PVC drum having a layer of sponge in the middle of drum. It is the easiest and cheapest form filter, suitable for residential units. A typical figure of sponge filter is shown in Fig 6.

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METHODS OF ROOFTOP RAINWATER HARVESTING Various methods of using roof top rainwater harvesting are illustrated in this section. 1. STORAGE OF DIRECT USE In this method, rainwater collected from the roof of the building is diverted to a storage tank. The storage tank has to be designed according to the water requirements, rainfall, and catchment availability. Each drainpipe should have a mesh filter at the mouth and first flush device followed by a filtration system before connecting to the storage tank. Each tank should have an excess water overflow system. Excess water could be diverted to the recharge system. Water from storage tanks can be used for secondary purposes such as washing and gardening etc. This is the most cost-effective way of rainwater harvesting. The main advantage of collecting and using rainwater during the rainy season is not only to save water from conventional sources but also to save energy incurred on transportation and distribution of water at the doorstep. This also conserves groundwater, if it is being extracted to meet the demand when rains are on. Fig 5 shows a typical fig of a storage tank.

FIG 5: A STORAGE TANK ON A PLATFORM PAINTED WHITE

2. RECHARGING GROUNDWATER AQUIFERS Groundwater aquifers can be recharged by various kinds of structures to ensure the percolation of rainwater in the ground instead of draining away from the surface. Commonly used recharging methods are:18

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Recharging of bore wells

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Recharging of dug wells.

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Recharge pits

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Recharge Trenches

Percolation Tanks.

Soak ways or Recharge Shafts

3. RECHARGING OF BORE WELLS Rainwater collected from the rooftop of the building is diverted through drainpipes to settlement or filtration tank. After settlement, filtered water is diverted to bore wells to recharge deep aquifers. Abandoned bore wells can also be used for recharge. Optimum capacity of the settlement tank/filtration tank can be designed based on the area of catchment, intensity of rainfall, and recharge rate. While recharging, entry of floating matter and silt should be restricted be...