2. COURSE OUTCOMES
• Discuss the water demand drafts and factors affecting the demand.
• Analyze the water distribution system and its water pipe appurtenances.
• Analyze the water quality, treatments and its Indian standards for drinking
water.
• Design the basic sewerage systems.
• Analyze the basic characterization of wastewater and treatment
processes.
• Describe the basic concepts for design of wastewater treatment plant and
wastewater disposal.
3. Environment
1) Everything Surrounding to us.
2) Environment is a very broad term, it includes all
things that is above, below, around us be it air,
water, or plant and animal life.
3) The complex of Physical, Chemical & Biotic factors
affecting an organism & ultimately determining its
form & survival is known as Environment.
4. Environmental science vs
Environmental Engineering
• Environmental science: Environmental science is an interdisciplinary
academic field that integrates physical, biological and information
sciences (including ecology, biology, physics, chemistry, zoology,
mineralogy, oceanology, limnology, soil science, geology, atmospheric
science, and geodesy) to the study of the environment, and the solution
of environmental problems.
• Environmental Engineering: It is the application of science or
engineering principles to improve the natural environment (air, water
and/or land resources), to provide healthy water, air & land for human
habitation & for other organisms, and to remediate pollution sites.
5. Importance of Environmental Sanitation / Importance & Necessity of
PlannedWater Supplies
1. Provides constant & reliable water supply for design population.
2. Provides Wholesome water for drinking, cooking, bathing, washing ,etc. so
as to keep disease away & promoting better health.
3. Supply water for fountains, gardens, etc. thus helping in maintaining better
sanitation & beautification of surrounding, thereby reducing environmental
pollution.
4. Ensures safety against fire by providing sufficient quantity of water to
extinguish it.
5. Attracts industries, thus helping in industrialisation &
modernisation of the society, consequently reducing
unemployment & ensures better living standards.
6. Help in promoting wealth & welfare of the entire Humanity as a whole.
6. Use ofWater
The following are the uses of water:
1. Domestic supply
2. Industrial supply
3. Irrigation
4. Preservation of aquatic life
5. Generation of electricity
...etc.
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7. Pure &WholesomeWater
Pure water: It is that water which contains only two parts of
Hydrogen & one part ofOxygen
Wholesome water: Water which is fit to use for drinking, cooking,
washing without any potential danger to human health.
• It will neither contain any chemicals or impurities in excess of which
may harm a human body nor any harmful bacteria.
• A water which is safe due to absence of harmful bacteria may or
may not be wholesome, but wholesome water will always be safe.
8. Palatable & PotableWater
• The water which is tasteful for drinking & asthetically pure, is
known as Palatable water.
• The water which is suitable for public water supply is known as
potable water. It has characteristics of both, Wholesome & palatable
water.
• In literal terms, potable water is safe to drink where as palatable
water is water at a desirable temperature, that is free from
objectionable tastes, odors, colors, and turbidity.
• So, water that is safe to drink but smells like rotten eggs is potable.
Water that is safe to drink and smells like nothing (water is odorless)
is palatable.
9. Water requirements
The following are the requirements of water:
1. It should be free from bacteria.
2. It should be colourless.
3. It should be tasty, odour free and cool.
4. It should not corrode pipes.
5. It should have dissolved oxygen and free from carbonic acid so
that it.may remain fresh.
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10. Characteristics ofWater
water can be checked and analysed by studying and testing their
physical, chemical, and microscopical characteristic.
characteristics of water:
1.Physical :
i. colour
ii. Taste and
odours
iii. Temperature
iv. Turbidity
2.Chemical:
i. Total solids and SS
ii. pH value
iii. Hardness of
water
iv. chloride content
v. Nitrogen
content
3. Microscopical:
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14. Data to be Collected forWater Supply Scheme
• Source of RawWater
• Quantity ofWater
1. Population
2. Water demand
3. Design period
• Quality of water
• Survey Data: topograpgical
maps of Intake, raising
• main ,WTP, location of ESR
• Plan or map of city
• Acquisition of land &
compensations to be paid to
the land owners & legal
complications
• Existing water supply position
of the town & possibility of its
expansion
15. Surface Source Of Water
Intake Works
Pumping
Rising Main
Water Treatment Plant
Elevated Service Reservoir
Distribution Systems
Flow Diagram of water supply Scheme
16. Open
Well
Pump House ESR Distibution
a)Village water supply scheme
Source
Intake
well
Jack
well
Flash
Mixer
Coagulation
Flaocculati-
on
Clarifier
Rapid sand
Filter
Clorin-
ation
Filter Water
Tank
ESR Distibution
b) CityWater Supply Scheme
Layouts of water supply schemes
17. Pricing of MunicipalWater Supplies
• In poor & developing country differential rates for various uses is permissible
( Rates for domestic uses < rates for commercial uses < rates for industrial
uses )
• When rates are heavily under-priced, the consumers waste water by
litres.
• Low water rates, thus, bring water management on a low priority area, and
leads to alround wastage & mismanagement of water supply schemes.
• Water rates in India for municipal siupplies are abysmally low, compared to
global standards.
18. Wastewater
Wastewater : is simply that part of the water supply to the community
or to the industry which has been used for different purposes and has
been mixed with solids either suspended or dissolved.
Wastewater is 99.9% water and 0.1% solids. The main task in
treating the wastewater is simply to remove most or all of
this 0.1% of solids.
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19. Waste Water
Sewage
• Liquid waste from toilets, baths and showers, kitchens, that is
disposed via sewers, trucking, or on site treatment systems
IndustrialWasteWater
• Waste water from industries of mines. Generally involves some on site
processing
20. Typeof Wastewater from household
• GrayWater -Washing water from the kitchen, bathroom, laundry.
• BlackWater:Water from flush toilet.
• YellowWater-Urine from separated toilets and urinals.
• BrownWater-Black water without urine or yellow water
21. Characteristics ofWastewater
Wastewater can be checked and analysed by studying and testing
their physical, chemical, and microscopical characteristic.
characteristics of water:
1.Physical :
i. colour
ii. Taste and
odours
iii. Temperature
iv. Turbidity
2.Chemical:
i. Total solids and SS
ii. pH value
iii. Hardness of
water
iv. chloride content
v. Nitrogen
content
3. Microscopical:
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22. Treatment Stages
• Primary: Mechanical treatment to reduce coarse solids, sand and dirt, oils
and grease
Note: Ideal as pre-treatment or for treating “surface” water (e.g. street water)
Note: Involves screening, sedimentation, skimming
23. Treatment Stages
• Secondary:Treatments designed to degrade biological content of sewage
(e.g. human waste, food waste) through aerobic biological processes
Note: Require aeration for bacterial and protozoan activities to degrade
organic compounds
Note: Effluent water and sludge are by-products
24. Treatment Stages
• Tertiary: Advanced stages of treatment to raise the effluent quality to
the standard required before it is discharged to the receiving
environment
Potential steps: Filtration, polishing, ponding (lagoons, wetlands),
nutrient removal, disinfection.
Note: Industrial contaminants remain an issue.
27. Common Options for Secondary SewageTreatment
Treatment
Process
Description Key Features
Activated Sludge
Process (ASP)
Oxygen is mechanically supplied
to bacteria which feed on
organic material and provide
treatment
Sophisticated process – many mechanical &
electrical parts, needs careful control of
operator; provides high degree of treatment.
Aerated lagoons Like lagoons but with
mechanical aeration
Not very common; oxygen requirement mostly
from aeration and hence more complicated and
higher operational and maintenance costs.
LandTreatment
(soil –aquifer
treatment – SAT)
Sewage is supplied in controlled
conditions to the soil
Soil matrix has quite a high capacity for
treatment of normal domestic sewage, as long
as capacity is not exceeded. Some pollutants,
such as P, are not easily removed.
