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Rainwater Harvesting System(DGB617)

2011/12 Semester 1 & 2

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Introduction! What is Rainwater Harvesting &

Utilization?

! Decentralized, environmentally sound solution

! Alternative Technologies to Augment Freshwater

Resources

! Avoid environmental problems caused by

conventional large scale projects using centralized

approaches

2

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!Definition! Rainwater harvesting is a technology used for

collecting and storing rainwater for human use.

Introduction

!Rainwater Collection! Rainwater is collected from rooftops, land surfaces

or rock catchments using simple techniques suchas jars and pots as well as engineered techniques.

3

Rainwater Harvesting System

! What is Rainwater Harvesting System?

! The system collect rainwater from various catchmentareas and store it in tanks for application such asirrigation.

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! Demand for Rainwater Harvesting" practiced for more than 4,000 years

" owe to the temporal and spatial variability of rainfall

" important water source in areas with significant rainfall butlack centralized supply system

" ood o tion in areas lackin in ood ualit fresh surface

Introduction

water or groundwater

! Rainwater Harvesting Technology! Application of appropriate rainwater harvesting technology

is important for the utilization of rainwater as a water resource

5

Source of Rainwater - Water Cycle

6

http://www.tradenote.net/images/users/000/159/296/products_images/Rain_Water_Harvesting___Recycling_Consultancy.jpg

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How Rainwater is Collected

7

http://www.greengaragedetroit.com/images/7/72/Rainwater-harvesting.jpg

8

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Rainwater Harvesting Outdoor Use

11

http://www.whiz-q.com/Merchant2/graphics/00000001/Rainwater_Illustration.gif

Rainwater Harvesting Common Use

12

Rainwater Harvesting Facilities in AcehRainwater Harvesting Facilities in AcehBuilt by South Korean StudentsBuilt by South Korean Students

Rainwater Harvesting Facilities inRainwater Harvesting Facilities inAlorAlor Supported by UNICEFSupported by UNICEF

http://www.ntust-isa.org/index.php?option=com_content&task=view&id=61&Itemid=64

Typical Layout for Rainwater Harvesting

Facilities

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Rainwater Harvesting System

Rainwater Harvesting System

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Principle of Rainwater Harvesting

! Rainwater Harvesting Principles

! capture non-potable waterat the point it falls

! a substitute for mains water in non-potable

applications

! alleviate the effect of heavy rainfall on flood-

risk areas

! saves energy by not using highly processed tap-

water to flush toilets

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Rainwater Harvesting SystemMain Components

PipingIt is used to convey rain water from the catchment areas to thecollection tank. Only approved type of pipe shall be used.

FilterIt is use to filter off foreign objects within the collected rain water

Collection TankIt is usually a concrete tank which durable and require minimummaintenance.

Overflow PipeThis is a feature incorporated into the tank. It is to release excessiverain water when the tank is full.

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Firs

t

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eyCom

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onen

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aterH

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esting

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.jpg

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TypesofR

ainw

aterH

arv

esting

Syste

ms

!

Desi

gnCon

sid

era

tion

s

!

dependsonsize&natureoftheca

tchmentareas

!

whetherthesystemsareinurbanorruralsettings

!

T

esofR

euirem

en

ts

!

Simpleroofwatercollectionsystems

!

Largersystemsforeducationalinstitutions,stadiums,

airportsandotherfacilities.

!

Roofwatercollectionsystemsforhigh-risebuildingsin

urbanizedareas

!

Landsurfacecatchments

!

Collectionofstorm-waterinurbanizedcatchments

19

Sim

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Larg

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22

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thecolle

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ater

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Lan

dSurfa

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ents

Pro

blem

Possibilityofhigh

ratesofwater

lossdueto

infiltrationintothe

ground.

Suita

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qualityofthe

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24

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pollu

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variouscouncilstohelp

filterstormwaterbeforeit

entersdrainsandour

riversandcr

eeks.

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Rainwater Harvesting System

! Benefits! Reduce water consumption (Save $$)

! Promote water conservation

! Excellent source of water for landscape irrigationwithout chemical

! Limitations! Limited and uncertainty of rain fall

! Can be costly to install depending on the size andcomplexity of the system (i.e. tank size, delivery

system)! Need skill workers to carry out maintenance work

END