Water resources

Pacific school of engineering Department of civil engineering

Guide By Group

Mimansha Pandya (E)

Prepaid By

Roll No.

Name

05 CHHOTALA HITESH B.

07 CHOVATIYA HARSH Y.

17 HADIYA SAGAR H.

28 MANDANI JIGNESH V.

61 VAVALIYA MAULIK A.

Table of ContentGlobal overview Volume of water stored in the water cycle’s

reservoirsThe water cycleWater usesThreats to fresh water resourcesVarious types of dam

Global Overview

While 67% of Earth’s surface is covered by water, only less than 2.7% of global water is freshwater. Most of the freshwater (2.05%) are locked in ice caps and glaciers. Only less than 0.7% is available for human use.

Over two thirds of the earth's surface is covered with water, 97.2% of which is contained in the five oceans. The Antarctic ice sheet, containing 90% of all fresh water on the planet, is visible at the bottom. Atmospheric water vapour can be seen as clouds, contributing to the earth's albedo.

Iceberg and Polar cap store most of the fresh wateron Earth

Volume of water stored inthe water cycle's reservoirs

Reservoirz Volume of water(106 km³)

Percentof total

Ocean 1370 97.25Ice caps & glaciers 29 2.05

Groundwater 9.5 0.68Lakes 0.125 0.01Soil Moisture 0.065 0.005Atmosphere 0.013 0.001Streams & rivers 0.0017 0.0001Biosphere 0.0006 0.00004

Competing water uses (I)

Threats to fresh water resources Climate change causes change in frequencies

of droughts and floods.Depletion of aquifers caused by over-

consumption as a result of population growth.Pollution and contamination by sewage,

agricultural and industrial runoff.

The Indian situation • Surface and ground water availability - 1,869 BCM of this, 40 % is not available.

Groundwater Consumption:

• 92% - Agricultural• 5% - Industrial • 3% - Domestic.

Surface water Consumption:

• 89% - Agricultural• 2% - Industrial• 9% - Domestic.

The Indian situationGroundwater is the major source of water in the country with 85% of the population dependent.

Groundwater water table decline - 33 centimeters per year.

What is a dam? A dam is a barrier built across a stream, river or estuary to

hold and control the flow of water for such uses as drinking water supplies, irrigation, flood control and hydropower generation etc.

Parts of a damDam body: Body forms the main part of a dam

as an impervious barrier Reservoir: It is the artificial lake behind a dam

bodySpillway: is that part of a dam to evacuate the

flood water from reservoir. Water intake structures: is a facility to

withdraw water from a reservoir. Sluiceway: Gerektiğinde baraj gölünü tamamen

boşaltmak, dolusavak kapasitesini azaltmak, akarsu mansabına bırakılacak suyu salmak amacına yönelik tesisler.

Diversion facilities: To redirect the streamflow from construction area

Upstream

Reservoir Dam

bodySpillway

Downstream

Classification of Dams According to dams height

If crest elevation and foundation level is greater than 15 m then it can be considered as a Large Dam.

If dam height is less than 15 m then Small Dam.

If dam height is greater than 50 m then High Dam

Classification of dams:Dams are classified on several aspects, some of the important aspects are as follow:1)Based on Hydraulic Design: Over flow dams (e.g. concrete dams) Non over flow dams (e.g. embankment dams)

2)Based on Structural Design: Gravity dams Arch dams Buttress dams

3)Based on Usage of Dam: Storage dams Diversion dams Detention dams

GRAVITY DAMS Gravity Dams use their triangular shape and the

sheer weight of their rock and concrete structure to hold back the water in the reservoir.

Sarıyar Dam – Sakarya River; Height= 90 m

Reservoir Capacity= 1.9 billion m3

ARCH DAMS Arch Dams utilize the strength of an arch to

displace the load of water behind it onto the rock walls that it is built into.

Karakaya Dam – Fırat River; Height= 173 m

Reservoir Capacity= 9,5 billion m3

BUTRESS DAMS Buttress Dams use multiple reinforced columns

to support a dam that has a relatively thin structure. Because of this, these dams often use half as much concrete as gravity dams

Elmalı II – Göksu River; Height= 42.5 m

Reservoir Capacity= 10 million m3

Thank you