About major introduction of hydrology

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2. PRESENTATION
TOPIC:
OVERVIEW OF HYDROLOGY
PRESENTED TO:
SIR HASSAN REHMAN
PRESENTED BY:
GROUP #2
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3. MEMBERS OF GROUP #2
1. ABDUL MUTAKABER
2. WASEEM ASHFAQ
3. HAFIZ WAQAS
4. NUMAIR AHMED
5. ZAHIRULLAH
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4. CONTENTS OF PRESENTATION
1. Hydrology.
2. Scope of hydrology.
3. Application of hydrology in civil engineering.
4. Hydrological Hazards.
5. Steps of Controlling of hydrological hazards.
6. Hazard control and civil engineering structures.
7. Conclusion.
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5. 1. HYDROLOGY
It is the science of occurrence, movement and distribution of
water above/below the land surface or in the atmosphere.
Surface water hydrology
Groundwater hydrology
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6. 2. SCOPE OF HYDROLOGY
• For knowing the sources of water in an area.
• For knowing quality and quantity of water in an area.
• For distribution of river water for full filling of different
area`s forming needs.
• Tremendous importance is given to the hydrology all over
the world in the development and management of water
resources for irrigation, water supply, flood control, water-
logging and salinity control, Hydro power and navigation.
• The maximum probable flood that may occur at a given site
and its frequency; this is required for the safe design of
drains and culverts, dams and reservoirs, channels and other
flood control structures.
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7. 3. Application of hydrology in Civil
Engineering
• Hydrology is used to find out maximum probable flood at
proposed sites e.g. Dams.
• The variation of water production from catchments can be
calculated and described by hydrology.
• Engineering hydrology enables us to find out the relationship
between a catchment's surface water and groundwater
resources.
• Hydrological investigation helps us to know the required
reservoir capacity to assure adequate water for irrigation or
municipal water supply in droughts condition.
• Used in connection with design and operations of hydraulic
structure
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8. 3. Application of hydrology in Civil
Engineering (continue…)
• Hydrology is an essential tool in planning and building
hydraulic structures.
• Hydrology is used for city water supply design which is based
on catchments area, amount of rainfall, dry period, storage
capacity.
• Dam construction, reservoir capacity, spillway capacity, sizes
of water supply pipelines all are designed on basis of
hydrological equations.
• Determining the water balance of a region.
• Mitigation and predicting floods, landslides and drought risk.
• Flood forecasting and flood warnings.
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9. 3. Application of hydrology in Civil
Engineering (continue…)
• Designing dams for water supply or hydroelectric power
generation.
• Designing bridges.
• Designing sewers and urban drainage system.
• Predicting geomorphologic changes, such as, erosion or
sedimentation.
• Assessing the impact of natural and anthropogenic
environmental change.
• It tells us what hydrologic hardware (e.g. rain gauges, stream
gauges etc) and software (computer models) are needed for
real-time flood forecasting.
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10. 4. Different hazards, their affects on
different projects, structures.
 Different hazards:
i. Flood.
ii. Heavy rain.
iii. Acidity rain.
iv. Snow fall on hilly areas.
v. Drought and poor quality of water.
vi. Heavy run off
vii. Cyclones
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11. i. Flood
An overflow of a large amount of water beyond its normal limits,
especially over what is normally dry land.
Effects:
• The floods in Pakistan began in late July 2010, resulting from
heavy monsoon rains in the Khyber PakhtoonKhwa, Sindh,
Punjab and, Balochistan regions of Pakistan, which affected
the Indus River basin. Approximately
• At its worst the flood waters covered roughly one-fifth of
Pakistan’s land area
• 18 million people were affected
• 2,000 people killed
• 12 million people’s homes were damaged or destroyed
• 2.2 million hectares of crops were destroyed
• 10,000 schools damaged or destroyed
• Economic impact
• Health issues
• Damage to infrastructure(roads and bridges) 11

12. i. Flood Effects:
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Crop Transport Rural Area

13. ii. Heavy rain
Heavy rainfall is one of the most frequent and widespread severe
weather hazards to affect human life. It
is defined as rainfall greater than 100 mm in 24 hours.
Effects:
• Heavy rainfall can increase the water levels which may effect
human life.
• Heavy rainfall can also result to form floods which can destroy
buildings, transport and livestock.
• Soil erosion.(sheet erosion)
• Landslide from mountains could fall &block roads.
• Stagnant (stand) water for many days could be cause many
water born diseases.
• Electric supply could get hampered.
• Collapse of slums. 13

14. ii. Heavy rain Effects:
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Heavy Runoff Flood due to Heavy rain

15. iii. Acidic rain
• Acid rain is caused by a chemical reaction that begins when
compounds like sulfur dioxide and nitrogen oxides are
released into the air.
• These substances can rise very high into the atmosphere, where
they mix and react with water, oxygen, and other chemicals to
form more acidic pollutants, known as acid rain.
Effects:
• Surface Waters and Aquatic Animals
• Forests
• Automotive Coatings
• Building Materials (such as statues, monuments)
• Visibility(visual range)
• Human Health
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16. iii. Acidity rain
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Crops
Aquatic Animals
Automotive Coatings
Forests
monuments
Health Effects

17. iv. Snow Fall on Hilly Areas
A fall of snow specifically, the amount of snow that falls in a
single storm or in a specific period.
Effects:
• Rock`s Decay due to freezing and thawing action.
• Suddenly increasing in river`s water level.
• Collapse of structures by different effects of snow and ice.
• Road`s blockage in hilly areas it is just due to snow.
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18. iv. Snow Fall on Hilly Areas
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19. v. Drought and poor quality of water
Water is available in an area from different sources, under
ground or surface water based. If the quality is not satisfied
and quantity is less.
Effects:
• Human life is impossible.
• Development of town for residential area or town is not
possible.
• Forming is not possible.
• Constructional activities are so difficult.
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20. v. Drought and poor quality of water
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Poor Quality of water
Drought

21. vi. Heavy run off
When water meet at a point which was driven from different
sources like rain or snow melting on hilly areas, and after
meeting at a point it start running in the form of river and
having many disadvantages.
Causes:
• Heavy rains
• Snow Melting
Disadvantages:
• Causes of flood.
• Land cutting
• Land sliding
• Having negative effects for residential, commercial areas
and forming land
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22. vi. Heavy run off
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23. vii. Cyclones
An extremely large, powerful, and destructive storm with very
high winds that turn around an area of low pressure.
Effects:
• One cyclone can destroy one town or more
Solution:
• The area where the formation of cyclone is possible like many
areas of USA the people can protect their lives by
permanently leaving this place
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24. vii. Cyclones
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25. 5. Steps of
hydrological
hazard control.
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26. Step 1. Hydrological investigation
Data collecting about hydrological hazards of any Area (during
service life or before starting of project) is called Hydrological
investigation.
These steps are included it hydrological investigation:
• Type of problem that are occurred or themes' occurrence is
possible.
• Finding Reason of problem.
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27. Step 2. report writing
After investigation it is a 2nd task, report writing of our results
which are gained by hydrological investigation.
After appropriate search for solution write the report in
following steps and getting permission for implementation of
solution by higher authority is include,
• Writing Reason of problem
• Its alternative(subway)
• Benefits of alternative (subway) adoption
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28. Step 3. solution of hazards
By taking these steps we can fix these hazards,
• Focus on alternative (subway)
• Apply the solutions
• Finely enjoy the best result
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29. 6. Structures
 Hazard control structures.
 Badly affected structures
There are many hazard control structures and the Structures which are
badly affected by hazards.
These are some structures which are badly affected by different
hazards:
• Dam`s hazards
• Weir, barrages and banks of rivers.
• Irrigation Canals and their banks.
• Bridges.
• Colonies and building structures.
• Roads and railways.
• Forming fields.
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30. i. Dam
A barrier constructed to hold back water and raise its level,
forming a reservoir used to generate electricity or as a water
supply.
Note:
Dam is A hazard control structure i.e. flood control structure,
but many times also face hazards like after described.
Objective:
• Preventing rain water or water from snow melting, from
flood formation
• For storage of water for future use for farming and other
uses.
• For electricity generating.
• For decreasing the quantity of water for less flow or
discharge.
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31. i. Dam
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Arch dam Gravity damDam

32. Hazards for dams
• Collection of silt or clay in dam which reduces its volume to
store water in it.
• Damage due to any reason, damage like cracking, corrosion
of material.
• Suddenly heavy flood that the efficiency of flood was not
recorded in previous 100 years.
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33. Dam’s Hazard controls
• Precautions during construction and designing
• Try to control at initial run off process from where a river is
formed but if possible.
• If a river is passing into more lengthy hilly area then
construct more than one dam one by one.
• Provide appropriate repair if possible.
• Re construct the dam if its present capacity of storage is less
than half of its intended designed capacity.
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34. ii. Weir, barrages and banks of rivers
Weir:
• A low dam built across a river to raise the level of water upstream
or regulate its flow.
Barrages:
• An artificial barrier across a river or estuary to prevent flooding, aid
irrigation or navigation, or to generate electricity by tidal power
Banks of rivers:
• In limnology, the study of inland waters, a stream bank or river
bank is the terrain alongside the bed of a river, creek, or stream.
Stream banks are of particular interest in fluvial geography, which
studies the processes associated with rivers and streams and the
deposits and landforms created by them.
Note:
• These are hazard control structures uses for controlling of water
from different sources and these may be affected by different
hazards 34

35. Objectives
• Weir is use for continues flow of water in river.
• Barrages artificial barrier across a river or estuary to prevent
flooding, aid irrigation or navigation or to generate
electricity by tidal power.
• Canal or river banks are used for protection of a town or
city that river`s or canal`s water could not enter in town.
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36. 36
Weir, barrages and banks of rivers
Weir
Barrage
Banks of rivers

37. Hazards for weir, barrages and banks
• Over water in river can neglect the objective of weir.
• Over flow can damage the structures like barrages or banks
of river or canals.
Hazard Control:
• Design the structures for next 100 years of maximum
discharge with a special.
• Lining on canal or river bank, prevent damages.
• Opening the doors of barrage before crossing the water onto
the top of barrage.
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38. iii. Irrigation canals
• Canals are used to deliver the water of river from one place to
another or from one river to another river.
• canals are facilities for having water at another place and they
are used as flood control.
Damage:
• Blockage which can spread canal`s water out-side of canal
like flood.
• Bank can destroy or damage.
• Due to fault water for forming will be less so fault will
neglect the purpose of canal and water will be waste.
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39. Precaution and repair
• Canal lining is best precision for preventing the canal to
damage.
• By canal lining discharge will be same and velocity will be
also same and blockage is impossible.
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Canal lining

40. iv. Levees
An embankment built to prevent the overflow of a river.
Note:
These are hazard control structures.
Damages:
• Due to heavy runoff in rivers, breakout of levees.
Repair:
• Preventing overflow by building barrages and weirs.
• Time by time repairing of levee`s height and width so that the
river water could not breakout from it.
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41. v. Flood walls
• A flood wall is a primarily vertical artificial barrier designed to
temporarily contain the waters of a river or other waterway
which may rise to unusual levels during seasonal or extreme
weather events.
• These are flood control structures.
Damages:
• It`s all damages are like concrete structures
and reasons are also like them
Repair:
• It`s repair is also like concrete structure`s
repair
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42. vi. Bridges
• A structure carrying a road, path, railway, etc. across a river,
road, or other obstacle.
Note:
• These structures are used for traveling for crossing the river
but can be badly affected by hazards which are below
described.
Damages :
• Due to abetments and pairs of bridge in river water
increases its level and velocity and the bed of river could be
damage.
• Due to high velocity soil will remove from the bed of river
and water may be damage foundations having less depth
foundations as Pakistan have low technology for pile
construction (i.e.) boring and soil may be clayey.
• If the river`s water having acidity, it can damage the
abetments or pair.
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43. Hazard control
• Change the technique of construction.
• Use appropriate materials and admixtures by using them
construction will safe, having long life and anti sulphates
and anti-acid these types of faults are possible in river Ravi
and may be in also others.
• Make the river`s bed safe by increasing distance between
pairs so that the water`s velocity remain same. It is A basic
phenomena that velocity and discharge are inversely
proportional to each other.
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44. vii. Forming fields
Hazard:
• Acidity due to acid rain.
Hazard control:
• Not appropriate solution but washing using canal water or
tube-well water is possible but so costly method.
 Other projects and structures:
• Colonies and building structures.
• Roads and railways.
Damages:
• For both projects flood is dangerous.
• Acidic rain is dangerous for structures like early corrosion
due to acid rain.
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45. Hazard control
• The case of flood can be handle same like flood`s problem
and it is a prime duty of departments like irrigation etc.
• Use material having resistance against acid so that the
construction could not damage.
 Experiment:
• Take a lightest acid and drop fall down it on concrete floor
and see the corrosion.
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46. 7. Conclusion
Today we has been learn about,
• Basic study of hydrology
• Different hydrological hazards
• Hazard control.
• Different hazard control structures.
• And finally different structures and preventing them from
hazards.
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47. ANY QUESTION?
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