Transcript PRESENTATION on STATUS OF THE PROJECT

PRESENTATION
on
FLOOD RISK MITIGATION MEASURES FOR THE RIVER
INDUS & NALLAHS IN LEH TOWN
by
Zainab Jalis, Amir Ali Khan, Sirajuddin Ahmed
REQUIREMENT OF FLOOD MITIGATION MEASURES
The Flood Mitigation Measures is required to take care of the following:
• Lessen the adverse impact of floods on socioeconomic conditions
• Controlling/ Preventing further damage to the infrastructure and
property;
• Restoring normal living conditions in the affected area.
• Saving human life
ABOUT LEH
• Leh, the capital of Ladakh is situated at an
altitude of 3,500m above MSL.
• The geographical coordinates of Leh are
34.17° North latitude and 77.58° East longitude
LEH
• Leh encompasses an area of 19.08 sq kms
within municipal limit
• As per census 2001, the population of Leh is
recorded as 28,639
• The temperature ranges from −40 °C in winter to +35°C in summer
• Rainfall is very low with annual precipitation of around 10cm mainly in the form
of snow.
• Air is very dry and relative humidity ranges from 6% to 24%.
HAZARD PROFILE OF LEH TOWN
Leh town is vulnerable to a large number of natural as well as man-made
disasters as follows:
• The Ladakh Region is situated in seismic zone IV close to Karakoram fault
zone, Eastern Karakoram, Ladakh which is highly prone to earthquakes.
•
Most disastrous among natural furies are flash floods which creates havoc in
Leh due to following reasons:
 Cloud burst
 Excessive melting of snow in the upper reaches of glaciers
 Sudden removal of cloud cover / long sunny days after a period of
sustained snow fall
•
Snow avalanche in snow covered mountainous regions of Leh
LEH FLASHFLOODS, AUGUST 2010
Recently Flash Floods has occurred in Leh on
August 5, 2010 , affected the whole Ladakh region.
Damage pattern
•
About 193 peoples were died & 200 were missing.
•
Approx 908 no. of houses have been destroyed in
Leh.
•
80% of Infrastructure was damaged i.e. roads &
bridges
•
Heavy damage to irrigation systems head works of
canals, protection works of rivers & canals.
•
Main hospital of Leh town (Sonam Norboo
Memorial Hospital) was totally damaged.
The impact of disaster in Leh was more because there
has not been any Flood Mitigation Measures in place.
MANITSELDING
NEED OF THE STUDY
•
Leh is situated in mountainous regions, which are most disaster prone
because of the topography and inaccessibility of affected areas.
•
Cloud burst occurred in mid last year is the recent example.
•
In Leh there is no Flood Mitigation Measure Strategy in place.
•
Keeping in view the peculiar geographic and topographical conditions
prevailing in Leh town.
•
Need for formulating and implementation of Flood Mitigation Measure
Strategic Plan is must to reduce the damages and making Leh a safer
town.
DRAINAGE PATTERN
•
River Indus flows south of the town
of Leh from east to west.
•
In the north of Leh town towards
Gangles, rivulet namely Leh Nallah
(Gangles Tokpo) with its tributary
streams namely Gyulang Tokpo and
Togar
Tokpo
form
the
natural
drainage system with their own
valley formation.
•
These
two
streams
meet
the
Gangles Topko at Horzey.
Leh town boundary
Leh Nallah
•
The Leh town has been growing in
the Gangles valley.
RECOMMENDATIONS
 Construction of Embankments near inhabited areas along River Indus & Leh
Nallah
• Embankment Design:
With the help of discharge data procured, Using Gumbels extreme distribution
function design discharge can be calculated.
RECOMMENDATIONS
TYPICAL SKETCH OF PROPOSED EMBANKMENT ON RIVER INDUS AT LEH
(FOR MAXIMUM FLOOD DISCHARGE FOR A RETURN PERIOD OF 100 YEARS)
RECOMMENDATIONS
Detention Basins
3 nos of detention basins have been
proposed
• one Detention Basin in the upper
reaches of Gangless,
• second at polo ground &
• third one at ice hockey ground
which will receive the diverted additional
water of the Flash Flood through a tunnel
and finally spreads in the detention basin.
At outlet point of detention basin a gabion
structure with suitable diameter RCC
pipes for controlled release of water shall
be provided. Early warning system should
be implemented so that alarm/signals can
be raised in any eventuality of raising the
water level in Nallahs.
RECOMMENDATIONS
Plan of Detention Basin at upper reaches of Gangles Nallah

Wire Crate / Gabion walls / Bunds in
Giamtsa, Gyalong & Shenam Nallah

Check Dams across the rivers /
Nallah

Channelization of River/ Nallah at
Vulnerable locations

Removal of Impediment to flow

Relocation / Re - settlement
Relocation & Rehabilitation of
encroachments on a nallahs is
required
THANK YOU