Flood Management

Subject : Hydrology & Water Resource Engineering Subject Code:- 2510602

Prepared By:Kansara Abhishek 151103106007Kotila Jayveer 151103106008Mistry Aditya 151103106009Pandya Dhrumil 151103106010Patel Kajal 151103106011

Guided by:Assi. Prof. Mamta Patel

Civil Engg. Dept.

Flood Management

The Indian rivers can be classified into four major groups:-

1. Himalayan Rivers2. Rivers on the central high lands3. Rivers on peninsula4. Rivers on the coasts

Indian Rivers and Floods

Three important rivers Himalayan rivers are Indus, Ganga and Brahmaputra.

These rivers flows in the north west region. This region covers the states like Jammu-Kashmir, Punjab, Haryana, Rajasthan and the parts of Himachal Pradesh.

Himalayan Rivers

The Ganga region covers the states of Uttarakhand, U.P., Bihar, Himachal Pradesh, West Bengal and Delhi.

The main flood problem in these region bring a lot of sediments, overspill their banks and change their course,

Brahmaputra is known for its huge and disastrous floods.

It covers Assam, West Bengal, Tripura, Manipur, Nagaland etc.

It is also called as the ‘the tears of Assam’.

It consists of Mewar high land, Bundelkhand plateau, Malwa plateau etc. These hifhlands gives he rise to the rivers like Narmada, Tapi, Sabarmati, Mahi, Mahanadi.

The floods in the river Narmada causes the damage to the property and life of Bharuch district in Gujarat.

The floods in the Tapi cause the widespread damage to the Surat.

Rivers of Central Highlights

Most of the peninsular rivers rise on the western ghats and flows towards the east to meet the Bay of Bengal.

River Godavari, Krishna, Kaveri, Koyana all non perenial rivers.

The region as a whole does not havea serious flood problems, except that on some rivers of Orrissa state

Rivers in the Peninsula

The rivers which originates on the western Ghats and flows toward west are called coastal rivers.

These are kali vasistha in Maharatstra, Mandwi and zuari in Goa.

These rivers are short in length and have to run over the steep slopes so have fast runoff.

Rivers on the coast

1. Intense Rainfall2. Topography of the catchment3. Sedimentation of rivers and reservoirs4. Obstruction in the river flow5. Failure of the dam6. Failure of the river embankment7. Inadequate cross drainage work8. Contraction of waterway

Causes Of Flood

The flood occurs because of heavy rains or melting of snow when discharge in the river is so high that its natural cross section is unable to contain it.

Flood control is require to reduce the flood damage.

Flood control is also known as flood management.

Flood Alleviation

There are two types of measures to mitigate the flood disaster:

1. Structural mitigation

2. Non-structural mitigation

The structural mitigation measures are:-

1. Storage reservoirs2. Levees3. Flood walls4. Channel improvement works5. Diversion of flood water to flood ways6. Construction of high earth platform7. Sluices

Structural Mitigation

A levees is an earth embankment .

It is sort of an earthen dam constructed along the river.

The construction of levees is more common than flood walls as it is more economical and convinent.

Levees

Levees

Earthen embankment for increased flood storage

i. They are easy to construct parallel to the river banks by available earth.

ii. Initial cost of construction is less.

iii. They prevent overflowing the banks.

iv. Maintenance is easy

v. It increases the storage capacity of the river

Advantages

When embankments fails during the high stage of the flood it suddenly creates catastrophic flood exactly like dam break.

During flood time round the clock maintenance is very mush essential against failure.

Due to the increase of river capacity velocity decreases also the depth of the river decreases with the time.

Drawbacks

Flood walls are used in the developed area where it is difficult to obtain enough land for the construction of levees.

A flood wall is a sort of gravity dam constructed along the river.

Flood walls are designed to withstand the uplift pressure like gravity dams.

Flood Walls

Flood walls

Flood wall to save a town from the flood disaster

Thank you