Adapting to Climate Change
in Asia’s Coastal Megacities
Kishore U. Gajbhiye
Additional Commissioner
Municipal Corporation of Greater Mumbai, India
Mumbai
Mumbai lies at the mouth of the Ulhas
River off the western coast of India, in the
coastal region known as the Konkan.
It sits on Salsette Island, partially shared
with the district of Thane.
Much of the city lies just above sea level,
with average elevations ranging from 10 m
(33 ft) to 15 m (49 ft). Northern Mumbai is
hilly, and the highest point in the city is
450 m (1,476 ft).
The city spans a total area of 603 km²
(233 sq mi).
Topography
• Merger of 7 islands in city area, 4 islands and hilly areas
in suburbs
• Surrounded by the Arabian Sea and Thane creek
• Much of the area is close to sea level
• Gravity drainage system designed in 1920s, affected by
high/low tides
• During high tide, flood gates are closed to stop ingress of
sea water.
• Result: No drainage of storm water, water logging/flood
occurs during heavy rains coupled with high tide
Presented by: Kishore U. Gajbhiye | Additional Commissioner, MCGM, India
Topography
• Network of drains below roads in city area and open
drains in suburbs
• Storm Water Drainage (SWD) Network
– more than 150 years old in city area
– designed for rainfall of 25 mm per hour and Run-off co-efficient of 0.5
• Brihan Mumbai Storm Water Drain Project
(BRIMSTOWAD Project) Report (1993) - the city is fully
developed and the change in land use pattern has led to
increase in Run off coefficient to almost 1.0
Presented by: Kishore U. Gajbhiye | Additional Commissioner, MCGM, India
Mumbai
Covers an area of about 437.71 Sq.
Km.
G/N
F/N
Houses about 11.9 Million people (c.
2001)
G/S
F/S
Population density of about 27,209
people per Sq. Km (c. 2001)
E
D
B
C
Approximately 60% population resides
in informal settlements
A
Approximately 27,68,910 structures
including residential, commercial and
industrial
Presented by: Kishore U. Gajbhiye | Additional Commissioner, MCGM, India
Mumbai: Position
• Between 18 and 19.2 Northern Latitude
• Between 72 and 73.0 Eastern Longitude
• East to West extends – 12 Km broadest
• North-South extending about 40Km
• Height – 10 to 15m above sea level
Presented by: Kishore U. Gajbhiye | Additional Commissioner, MCGM, India
Population of Million
Growth of Population 1901 - 2001
14
12
10
8
6
4
2
0
1901
1911
1921
1931
1941
1951
Year
Presented by: Kishore U. Gajbhiye | Additional Commissioner, MCGM, India
1961
1971
1981
1991
2001
Growth %
% Growth of Population During 1901-2001.
80
70
60
50
40
30
20
10
0
1901
1911
1921
1931
1941
1951
Year
Presented by: Kishore U. Gajbhiye | Additional Commissioner, MCGM, India
1961
1971
1981
1991
2001
Floods in Mumbai
• The thrusts of disaster management in Mumbai since the
year 2005 is floods during the monsoon.
• Mumbai and Singapore both get about 2500 mm. of
rainfall. However, Singapore rainfall is better distributed
over the year, while Mumbai rainfall is during two months
of July and August.
• Rapid urbanization has substantially increased the
population.
Presented by: Kishore U. Gajbhiye | Additional Commissioner, MCGM, India
Increasing population
• Habitation comes first, water supply next, roads
thereafter and storm water drainage at the last.
• Construction of houses is largely at private initiatives
while storm water drainage is to be done by the
Municipal Corporation.
• Analysis by Shri Sanglikar, retired DMC shows that the
ratio of number of flooding days with rainfall of more than
75 mm increased from 1:7 in the 40’s to 1:1 in the 70’s to
1.5:1 in the last decade.
Presented by: Kishore U. Gajbhiye | Additional Commissioner, MCGM, India
Many areas of Mumbai below sea-level
• Mumbai is originally a group of 7 islands. Many areas of
the city are reclaimed from the sea and are at a level of 5
meters and above from the low tide level.
• The high tides during July and August are about 4.80
meters and occur between 12.00 mid-noon to 02.00 p.m.
in the few days after the full moon day (Amavasya).
• This situation occurs only for 4 days in a month for about
5 hours each.
• Heavy rainfall just before these days can create panic
situations since water cannot discharge into the sea.
Presented by: Kishore U. Gajbhiye | Additional Commissioner, MCGM, India
Low-lying area in Mumbai
• Railway lines are typically about 10 meters above low
tide level and the Subways are very close to high tide
level.
• Western Railway 43 culverts, Central Railway 35
culverts and Harbour lines 27 culverts.
• In addition there are 82 chronic flooding spots.
Presented by: Kishore U. Gajbhiye | Additional Commissioner, MCGM, India
Disaster Preparedness
• MCGM had put 196 temp. pumps to discharge water
• 6 Search and Rescue teams zone-wise are kept ready
under the fire brigade
• 600 personnel from Civil Defence and 10 persons per
Ward from an NGO – Aniruddha Academy were kept
ready
• 288 retaining walls in 74 places have been undertaken
by the Slum Improvement Board
• BEST keeps 500 buses ready
Presented by: Kishore U. Gajbhiye | Additional Commissioner, MCGM, India
Mithi River
• Mithi river is the boundary between South Mumbai and
western suburbs and also divides the western and eastern
suburbs. Flooding caused havoc in 2005.
• In Phase-I, 5.68 lakhs cu.m. silt has been removed.
• 3.70 cu.m. lakhs cu.m. silt has been removed in Phase-II after
March 2007.
• 2652 residential and 1148 commercial structures removed.
• 1769 residential and 349 commercial structures rehabilitated
• Additional bridges at Kranti Nagar and Kurla-Kalina Road
started.
Presented by: Kishore U. Gajbhiye | Additional Commissioner, MCGM, India
Storm Water Drainage
• Typically a city can cope up with 10 per cent of annual rainfall
in a day. On 26th July 2005, almost 35% of annual rainfall
occurred on a single day.
• Hon’ble Prime Minister sanctioned a special grant of Rs. 1200
crores outside JNNURM as 100% subsidy.
• The work involves widening of drains and construction of
pumping stations.
• Rehabilitation of slums up to 01.01.2000.
• An amount of Rs. 280 crores has been spent by December
2008 and we will be able to ask for the next installment.
Presented by: Kishore U. Gajbhiye | Additional Commissioner, MCGM, India
Future Plans
• Sea level is increasing by 3 mm. per year.
• Additional measures such as gates on Vihar and Tulsi may be
necessary.
• Holding ponds upstream of airport in Mithi would be
necessary since widening in the tidal portion does not help at
high tide times.
• Delay by Airport Authority in widening Mithi River under the
runway, a cause of concern.
Presented by: Kishore U. Gajbhiye | Additional Commissioner, MCGM, India
The Disaster Management Act, 2005
and Its Implications on Greater Mumbai
Presented by: Kishore U. Gajbhiye | Additional Commissioner, MCGM, India
Hierarchy of Authorityas per the DM Act-2005
NDMA
Sec-3
State DMA
Sec: 14
District DMA
Sec: 25
Local Authority
Sec: 41
Presented by: Kishore U. Gajbhiye | Additional Commissioner, MCGM, India
Coordination Institutional Mechanisms
• State Disaster Management Sub-Committee for Mumbai
• Headed by ACS (Home)
• Ward wise Disaster Management Committee Headed by
Assistant Commissioner of Ward
Presented by: Kishore U. Gajbhiye | Additional Commissioner, MCGM, India
Coordination
• Effective coordination
among all agencies
necessary for effective
response
• Regular preparedness
meetings of institutional
mechanism
Central
Railway
Western
Railways
Mantralaya
GoM
Fire
Brigade
Police
MCGM
Traffic
Control
MMRDA
Metrology
Dept
Presented by: Kishore U. Gajbhiye | Additional Commissioner, MCGM, India
BEST
Effects of Disaster
Presented by: Kishore U. Gajbhiye | Additional Commissioner, MCGM, India
Presented by: Kishore U. Gajbhiye | Additional Commissioner, MCGM, India
Presented by: Kishore U. Gajbhiye | Additional Commissioner, MCGM, India
Presented by: Kishore U. Gajbhiye | Additional Commissioner, MCGM, India
Presented by: Kishore U. Gajbhiye | Additional Commissioner, MCGM, India
Where We Went Wrong ?
• Communication System fully collapsed.
• No single point relief and rescue center at many places.
• Disaster Management System not designed for worst.
• Low level of awareness among people.
• Unorganized mobilization of resources.
Presented by: Kishore U. Gajbhiye | Additional Commissioner, MCGM, India
Mumbai vis-à-vis the World
Sr.
City
Country
Agglomeration (c. 2003)
1. Tokyo
2. Mexico City
Japan
Mexico
33,850,000
22,050,000
3. New York
USA
21,850,000
4. Seoul
South Korea
21,850,000
5. Sao Paulo
6. Delhi
Brazil
India
19,850,000
18,550,000
7. Los Angeles
USA
17,650,000
8. Osaka
Japan
16,700,000
9. Jakarta
Indonesia
16,550,000
India
11,900,000
10. Mumbai
Presented by: Kishore U. Gajbhiye | Additional Commissioner, MCGM, India
Mumbai’s Population Dynamics
• Average population density
– 27,209 persons per Sq. Km (population / area)
• Majority of the population lives in the suburbs and
commutes to the city area in south for work in the
morning and back home in the evening
• Case Study - Ward ‘A’ (South Mumbai)
– Daytime population : 45,00,000 persons
– Density : 3,94,390 persons / Sq. Km.
– Nighttime population : 2,00,000 persons
– Density : 17,528 persons / Sq. Km.
Presented by: Kishore U. Gajbhiye | Additional Commissioner, MCGM, India
Indian Monsoon is Unique!
3000
Jan
2500
Feb
2000
Mar
Apr
1500
May
Jun
Jul
1000
Aug
500
Sep
Oct
To
ky
o
Se
ou
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Nov
Sh
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N
Si
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or
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0
Dec
Total
Mumbai AAR 2401mm
July average rainfall 868 mm > London’s annual 611 mm
Singapore also receives 2150 mm, but spread throughout the year (max
monthly is 304 mm in Dec; BOM in a day!)
Presented by: Kishore U. Gajbhiye | Additional Commissioner, MCGM, India
Indian Monsoon is Unique!
Rainfall in major Indian cities (mm)
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
Total
3000
2500
2000
1500
1000
500
Over 70 -95% rainfall in 4 months
So well-planned approach required for managing urban flooding
disasters in Indian cities
Presented by: Kishore U. Gajbhiye | Additional Commissioner, MCGM, India
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Average Rainfall in Mumbai
Presented by: Kishore U. Gajbhiye | Additional Commissioner, MCGM, India
Average Rainfall in Mumbai
Presented by: Kishore U. Gajbhiye | Additional Commissioner, MCGM, India
Sea Level/ Tidal Information
Presented by: Kishore U. Gajbhiye | Additional Commissioner, MCGM, India
Dates to watch in 2009
• Notable tide levels (at Apollo Bunder) are
– June 2009:- 4.95, 4.97 and 4.90 m from 24-26 June 2009
– July 2009:- 5.01 m., 5.05 m. and 4.94 m. from 23-25 July 2009
– August 2009:- 4.81, 4.94 and 4.92 m. rfom 20-22 August 2009
Presented by: Kishore U. Gajbhiye | Additional Commissioner, MCGM, India
Annual Increase in Sea Level
• Recent studies (Unnikrishnan, et al., 2006) indicate a
rate of rise of 0.78 mm/year for Mumbai based on
analysis of data from 1878-1994.
Presented by: Kishore U. Gajbhiye | Additional Commissioner, MCGM, India
Effect of Urban Heat Island on Hydrologic Processes
Rising Heat and Cloud Formation as a Result of the
Urban Heat Island Effect
http://www.gsfc.nasa.gov/topstory/20020613urbanrain.html
Urban Heat Islands Increase Rainfall Rates around cities by 48-116 % (NASA)
Winds Interact with Urban-induced Convection to
Produce Downwind Rainfall
http://www.gsfc.nasa.gov/topstory/20020613urbanrain.html
Preventive Measures Undertaken
• In order to avoid flooding & water logging, the Municipal
Corporation of Greater Mumbai carries out number of
activities such as:
–
–
–
–
–
–
–
–
Systematic desilting of Storm Water Entrances, laterals & manholes.
Desilting of open/ dhapa/ pipe/ arch/ box drains.
Desilting of minor and major nallas, outfalls.
Replacement of dilapidated Storm Water Drains.
Providing additional Storm Water Entrances.
Conversion of dhapa drains in to pipe drains.
Augmentation & repairs of drains & Nallas.
Removal of obstructions from the drains/ Nallas.
Presented by: Kishore U. Gajbhiye | Additional Commissioner, MCGM, India
Long Terms Measures
• In 1990, BRIMSTOWAD Consultants carried out
scientific study of following aspects:
– The existing condition of Storm Water Drain system and the topography
surrounding it.
– Repairs/reconstruction of Storm Water Drain System.
– Preparation of update plans.
– Analysis of present system and increasing its capacity considering
rainfall of 50 mm per hour.
Presented by: Kishore U. Gajbhiye | Additional Commissioner, MCGM, India
Proposed Categories of Works & Fund Requirement
Rs. in Crores
Categories
Unit
Rehabilitation of
Old SWD System
24.45 Kms
203.62
Widening &
Training of Nalla
102.95 Kms
153.33
272.31
283.27
708.91
Pumping Stations
8 Nos
148.00
111.00
29.00
288.00
504.95
383.31
312.27
1,200.53
Total
City Area
Presented by: Kishore U. Gajbhiye | Additional Commissioner, MCGM, India
Western
Suburbs
Eastern
Suburbs
TOTAL
203.62
BRIMSTOWAD Report
• M/s.Watson Hawksley India Pvt. Ltd. were appointed as
consultant in 1989 to study the whole SWD system.
• Their report, submitted in 1993, is called
“BRIMSTOWAD” Report i.e. Brihanmumbai Storm
Water Drainage
Presented by: Kishore U. Gajbhiye | Additional Commissioner, MCGM, India
Status of BRIMSTOWAD Project
• Projects in two phases
• Phase I –
–
–
–
–
–
Consists of 20 works
Cost of works 356 crores
Works completed - 10 nos
Work in progress - 10 nos
Expenditure upto December 2008 – 280 cr.
Expected date of completion – March 2009
• Phase II
– Nos of works under taken – 38
– Out of 38 works 27 works are in progress. Tenders are being prepared for
remaining 11 works.
– Total cost of works - 843.45 cr.
– Expected date of completion – March 2011
Presented by: Kishore U. Gajbhiye | Additional Commissioner, MCGM, India
BRIMSTOWAD Project
• Projects being carried out under BRIMSTOWAD Project
with the aid of Government of India.
–
–
–
–
GIS based urban Storm Water Drain management system.
Hydro mechanism of Storm Water Drain System.
Flood warning system
Rehabilitation / upgradation of nallas/ storm water system
Presented by: Kishore U. Gajbhiye | Additional Commissioner, MCGM, India
Major Recommendations
•
Change of design criteria from 25 mm/hr to 50 mm/hr. rainfall intensity and
coefficient of runoff as 1.00 from the earlier value of 0.50.
•
Rehabilitation of old/dilapidated SWD system in the City.
•
Augmentation of the SWD system for the new design criteria with tidal
effects.
•
Training, widening and deepening of nallas.
•
Augmentation of railway culverts at various flood prone areas.
•
Removal of obstructions of water mains, cables, etc. in the SWD system.
•
Removal of encroachments, structures coming in the water courses.
•
Provision of pumping stations at the city outfalls at Haji Ali, Love Grove
(Worli) and Cleaveland Bunder .
Presented by: Kishore U. Gajbhiye | Additional Commissioner, MCGM, India
Implementation of BRIMSTOWAD Report
•
•
•
•
•
•
Total cost of improvements suggested in the Report was Rs. 616.30 Cr.
(Figures based on 1992 prices and planned span of 12 years) Works could not be
taken up systematically mainly because of
» Financial constraints
» Encroachment on sites
In the past 10 years, works worth about Rs. 260 Cr. only could be completed.
At today’s prices:• Cost of the remaining Project works Rs. 1200 Cr.
• Cost of rehabilitation of Project Affected Persons - Rs. 600 Cr.
After the experience of the 26th July 2005, the MCGM has taken up implementation
of the BRIMSTOWAD Report on top priority. Works are proposed to be completed in
four years .
The Central Government has been requested for financial assistance. Technical
Appraisal of the Project has been completed by the CPHEEO and the Project is also
cleared by the EFC. The Project is awaiting final approval of the Cabinet Committee
on Economic Affairs.
Presented by: Kishore U. Gajbhiye | Additional Commissioner, MCGM, India
Flood Warning Systems: Initial Steps
• Automatic rain gauges to study exact pattern of the rain all over
Mumbai city & suburb
• Fire brigade being first respondent and on 24 hours alert, the rain
gauges will be installed at 26 fire brigade stations – across Mumbai
• This rain gauges data transmitted to control room every 15 minutes
• The rain gauges can be further calibrated to give alarm at prefixed
rainfall intensity
• This data will serves as warning and evacuation signal if required
• The approximate cost of equipment / system is Rs. 2 Crores
• Expertise from IIT Bombay for Early Warning System being utilized
Presented by: Kishore U. Gajbhiye | Additional Commissioner, MCGM, India
The MCGM’s EOC
• An Emergency Operations Center is equipped with:
–
–
–
–
–
–
–
–
An array of communications systems
Television sets tuned to major news channels
Networked Computer Systems with DM Software
Video Conferencing Setup
Conference and Press Rooms
Water Supply and Ration Stocks
Uninterruptible Power Supplies with Generators
Pantry, Dormitory and Toilet facilities
• Thus, it is a self-sufficient control center built to
withstand and outlast disasters
Presented by: Kishore U. Gajbhiye | Additional Commissioner, MCGM, India
Communication in Disaster Management
• Land lines, Hot lines, Mobile phones - both GSM and CDMA
• Ham radio , VHF wireless sets , Video conferencing
• TETRA (Terrestrial Trunk Radio Access)
• TETRA will give all voice , data and video
• Transfer from one location to other location
• Satellite phones –These phones are fail proof and work under all
conditions.
Presented by: Kishore U. Gajbhiye | Additional Commissioner, MCGM, India
Works being carried out under Brimstowad Project
• Construction of pumping stations at LGP, Hajiali, Cleavland Bunder,
Irla nallah.
• Proposed pumping stations at Britania Outfall, Mahul Creek, Mogra
nallah and Khar Danda
• 45 Outfalls which are below mean sea level will be closed by gate
type mechanism.
• Brimstowad report 1992 is reconciled by 0.5 x 0.5 mtr. GIS mapping.
Presented by: Kishore U. Gajbhiye | Additional Commissioner, MCGM, India
Seismic Microzonation
• Seismic Microzonation of Mumbai City.
• Municipal Corporation of Greater Mumbai is planning to carry out
Seismic microzonation
• A grid of 1km x 1 km would be selected for microzonation details.
• Hazard maps will be produced with the data of soil, water table,
demographic details, geotechnical details.
• The End product would be a good Disaster Management Plan.
Presented by: Kishore U. Gajbhiye | Additional Commissioner, MCGM, India
Rain Gauges & Flow Meters
• The live rain data from 30 weather stations make it possible to warn
the concerned staff when rain exceed the prescribed limit (10 mm) in
15 minutes.
• It is proposed to upgrade the system by providing some stand by
weather stations as well as providing additional weather stations.
• As a step towards flood forecasting MCGM is installing two flow
meters so that, early warning of rising level of water in low lying
areas can be given to respective officials as well as citizens.
Presented by: Kishore U. Gajbhiye | Additional Commissioner, MCGM, India
Communication System
• MCGM will be installing a fail proof communication system which will
have benefits of transmitting voice, data and video throughout the
Mumbai City.
• It will help the officials to judge the exact scenario at field and have
proper decision by coordinating the respective stakeholders.
• MCGM is also planning to have its own VHF system as a last but
100% sure way of communication. For this purpose MCGM’s own
frequency will be operated.
Presented by: Kishore U. Gajbhiye | Additional Commissioner, MCGM, India
Control Mechanism: Emergency Operation Center
• EOC contributes to the successful execution of the meticulous
planning
• It is the Command and Control Center for all rescue operations
• It serves as a Research & Development Unit
• It also serves as a Training Center
Presented by: Kishore U. Gajbhiye | Additional Commissioner, MCGM, India
108 DISASTER HELPLINE
Presented by: Kishore U. Gajbhiye | Additional Commissioner, MCGM, India
Communication with HOT lines
Presented by: Kishore U. Gajbhiye | Additional Commissioner, MCGM, India
Technology and Disaster Management
• Floods: Automatic Rain gauges, Flow meters, Velocity
Meters, Doppler Radar Satellite images.
Presented by: Kishore U. Gajbhiye | Additional Commissioner, MCGM, India
Rain Gauge Installation
MCGM has installed automatic rain
gauges at 26 fire brigade stations, so as
to know exact pattern of the rain all over
Mumbai city & suburb.
This rain gauges data is transmitted to
control room every one hour.
The rain gauges can be further
calibrated to give alarm at prefixed
rainfall intensity. (above 20mm rainfall)
These data serves ultimately as warning
and evacuation signal if required.
Fire brigade being first respondent and
on 24 hours alert, the rain gauges are
installed at fire stations.
Presented by: Kishore U. Gajbhiye | Additional Commissioner, MCGM, India
Coastal Regulatory Zone
• Within 500 mt of High Tide Line (HTL) development is
regulated by
– Maharashtra Coastal Zone Management Authority (MCZMA) for project
costs upto Rs. 50 Million
– By MOEF, GoI for project cost beyond Rs. 50 Million
• No development is permissible in CRZ I, i.e area
between High Tide Line & Low Tide Line
Presented by: Kishore U. Gajbhiye | Additional Commissioner, MCGM, India
Coastal Management Zone
• Final sanction of MOEF is not granted suggestions/objections invited
• “Setback Line” is proposed to be earmarked based on
various parameters. Development will be permissible on
landward side of ‘Setback Line’
Presented by: Kishore U. Gajbhiye | Additional Commissioner, MCGM, India
Local Government Level (Municipal Level)
• DC Regulations 1991 - DC Regn.No.16(b) governs development
within 9 Mt from edge of minor water course of 15 Mt from edge of
major water course. DC Regn 16(g) governs the datum level
depending on topography & drainage aspects
• Development Plan: It shows No Development Zones where normal
development is not permissible
• Building Proposal Section: It insists remarks of storm water drainage
department for every proposal (for proper surface drainage
arrangement) & compliance / completion certificate there of before
granting occupation permission.
Presented by: Kishore U. Gajbhiye | Additional Commissioner, MCGM, India
Adaptation Strategy
•
Regulatory Mechanism at Apex Level - Government of India
– Coastal Regulatory Zone
– Coastal Management Zone
– Ministry of Environment & Forests
– National Building Code
•
Regulatory Mechanism at State Level - Maharashtra State
– Maharashtra Regional Town Planning Act
•
Regulatory Mechanism at local level - BMC
– Mumbai Municipal Corporation Act 1888
– Development Control Regulations
– Development Plan
– Corporation Resolutions/ policy
Presented by: Kishore U. Gajbhiye | Additional Commissioner, MCGM, India
Adaptation Strategy Implemented
•
•
•
•
•
•
•
•
•
Regulatory Mechanism
Structural Programs such as JNNURM
Awareness among citizens
NGO participations
Training of Citizens and government officials
Practical hands-on experience
Co-ordination between different agencies
High-tech communication facilities
Continuous up gradation of disaster management plan with
international expertise
Presented by: Kishore U. Gajbhiye | Additional Commissioner, MCGM, India
Thank You