Climate change Adaptation and Natural DisastersPreparednessin the Coastal Citiesof North Africa

Adaptation and ResilienceAction Plans for Alexandria, Casablanca and TunisBonn, June 4, 2011

� A World Bank team has managed the study implemented by the consulting consortium of French EgisBCEOM , IAURIF, BRGM

� National counterparts in Egypt, Morocco and Tunisia fully involved in the Urban Risk Assessment s and the pre paration of the Adaptation and Resilience Action Plans, June 2009-2011

� Support of the Marseille Center for Mediterranean I ntegration, the Arab Academy for Science ,Technology and Mariti me Transportation (Egypt), and the European Space Agen cy.

� Financial support from Global Facility for Disaster Risk Reduction (GFDRR) and the NTF-PSI,TFESSD trust fund s

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Broad backing, participation in the study

OVERVIEW

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Increasing disasters, climate change impacts

OVERVIEW

� Climate downscaling scenarios, probabilistic risk a ssessments carried out for Alexandria, Casablanca , Tunis, Bou regreg Valley

� Urban risk assessments for the present time and for 2030, selected as sufficiently relevant to present decisi on-makers

� Economic valuation of potential losses and damages showing costs of over $1billion for each of the cities stud ied, of which 20 to 25% directly due to climate change, to be further refin ed

� Adaptation and Resilience Action Plans developed to respond to main risks: seismic and tsunamic, land subsidence, marine submersion, coastal erosion, flooding, and water sc arcity

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Study coverage and methodology

OVERVIEW

Climate findings and future projections

� Increases in ambient temperatures expected between 1.0C and 1.5C in all cities

� Climate downscaling points to lower total rainfall but more extreme weather events

� Sea-level rise conservatively estimated at 20 cm by 2030, but higher estimates possible

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OVERVIEW

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Urban risks on the rise in all cities studied

OVERVIEW

� The study internalizes the uncertainty related to the climate change projections, emphasizes the need to focus on “no-regret” measures, valid under many scenarios. It a lso provides decision-makers with adaptation cost-curves

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No-regret measures, adaptation cost curves

OVERVIEW

Reducing the risks: overlapping actions

� Adaptation and resilience require multiple responses, often overlapping

� Most cost-effective measures are the institutional and urban planning measures

� Infrastructure investments also needed, priority actions required for high-risk areas

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OVERVIEW

Institutional and preparedness measures

� Emergency responses and civil protection readiness

� Public information and early warning systems

� Climate and natural risks monitoring and mapping

� Central and local roles in adaptation and resilience

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OVERVIEW

Urban planning providing risk-protection

� Adapting the existing city and reducing urban risks

� Planning future expansions in low-risk zones

� Criteria for the design of new urban developments

� Climate-smart design and building guidelines

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OVERVIEW

Infrastructure improvements also required� Coastal defenses against

submersion, coastal erosion

� Urban flood protection, drainage systems upgrades

� Seismic and subsidence risks mitigation programs

� Water resources supply and demand management

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OVERVIEW

Steering urban grown away from risk areas

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ALEXANDRIA

� Urban risk assessment carried out in partnership with the Arab Academy based in Alexandria

� City expected to grow from 4.1m to 6.8m by 2030 (65% rate) putting pressure on the site

� Physical constraints coupled with risks call for growth away from low-lying areas

A fragile site historically below sea-level

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� Built on a coastal ridge, the city is caught between the sea, lagoons and former lakes

� Agricultural land reclaimed from the marshes is protected by the ancient Mohammed Ali sea-wall

� Low-income informal housing is located in the areas below sea level next to Lake Maryut

ALEXANDRIA

Old, high-density and vulnerable building stock

� Alexandria’s formal building stock mostly consists of older and low-quality structures

� These are vulnerable to natural disasters, represented by red and magenta in the map.

� Patterns of high-density occupancy in such areas multiply the vulnerabilities

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ALEXANDRIA

Seismic and tsunamic risks� Seismic risk is considered

low, but compounded by land subsidence

� The historical record of devastating tsunamis goes back to 365 AD and 1303 AD, with reported wave heights of 1m and 2.9m respectively

� Recurrence is estimated to 12% probability in 100 years, 6% in 50 years, and 2.5 % in 20 years, considered low

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ALEXANDRIA

Land subsidence risks

� Satellite earth observation imagery confirms the presence of land subsidence in 9 % of measured points

� Subsidence seems higher in areas where urban infrastructure has been built in the past decades

� Red polygons indicate the areas most affected

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ALEXANDRIA

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Marine submersion and coastal erosion risks

ALEXANDRIA

� The Corniche road, recently built on reclaimed sea-s hore, has aggravated storm surges by altering the sea-bed slo pe

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Coastal erosion aggravated by infrastructure

Urban flooding and water scarcity risks

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ALEXANDRIA

� Rainfall reaches 100 mm/day for a 100-year event, and flood protection is limited to 2-year recurrence

� Lake Maryut water level is kept between -2.8 to -2.6 m below sea level via pumping stations

� Nile water supply is likely to become insufficient by 2030 with increasing urban demand

� Egypt has suffered from limited ability for natural disasters prevention, and its response capacity has been cons trained by a highly centralized decision-making structure

� The Information and Decision Support Center (IDSC) reporting to the Cabinet, cannot count on significant decentr alized response capacities. Recent natural disasters (Sina i flash floods in 2010) show that Government response is in adequate

� Climate change, questioned until recently by the Eg yptian Meteorological Agency, is finally beginning to be r ecognized as a real challenge, with IDSC and EEAA sharing responsi bilities

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Limited prevention and response capacities

ALEXANDRIA

� Natural disasters and climate change impacts would cost the city of Alexandria approximately $1.72 billion (in Net Present Value) during 2010 to 2030 period. Climate Change r elated impacts are estimated to be about 18% of the total estimated cost. These calculations are however considered pre liminary.

� With respect to climate change related health issue s (mostly diarrheal diseases, and malaria), the total annual average costs are around 278 MLE, equivalent to about 0.30% of th e city’s yearly annual GDP. The indirect costs are estimated at around three times the direct costs.

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Economic valuation of potential damages, losses

ALEXANDRIA

Urban planning responses� GOPP to orient future urban

growth away from areas at risk via the forthcoming Master Plan to 2030

� Critical areas of Abou Qir and El Max to be protected from marine submersion, flooding risks

� Strategic Urban Plan to include climate-resilient urban development plans

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ALEXANDRIA

Infrastructure investments required

� Build further sea defenses to limitcoastal erosion and marine submersion due to storm surges

� Promote reuse of waste water for agricultural purposes in lieu of Nile water to reduce future demand

� Conduct seismic micro-zoning, and deeepen the understanding of tsunamic risks and of the vulnerabilityof the housing stock

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ALEXANDRIA

� Strengthening monitoring and early warning systems, in order to better protect the city against extreme weather events

� Preparation and self-protection against fast-impact ing phenomena, via information and education campaigns

� Insuring against natural risks, via publicly suppor ted schemes that would protect public as well as private invest ments

� Improving the capacity to integrate the forecasting of (fast-onset) natural risks with (slow-onset) climate chan ge impacts

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Adapting institutions to manage urban risks

ALEXANDRIA

MULTIPLE WATER RELATED RISKS

� Current population of 3.3m expected to grow to 5.1 by 2030 (55% increase)

� Urban exposure to coastal erosion and flooding are high, marine submersion critical in some areas

� Further urbanization may worsen flooding risks if I is not climate-smart

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CASABLANCA

Climate downscaling results for 2030

� Ambient temperatures increase up to 1.5C

� Overall decrease of annual rainfall up to 20%, but likely increase of extreme episodes, although models differ widely on results

� Increase in the likelihood and duration of dry spells and summer heat-waves

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CASABLANCA

Casablanca (pq90)

-25-20-15-10

-505

1015202530354045

CNRM_A1B MET_A1B MPI_A1B ARPG_A1B ARPG_A2 ARPG_B1

Large concentration of sub-standard housing

� Substandard units constitute 28% of all housing stock, with 11% categorized as slums.

� These extend across the city, and occupy flood-prone areas and areas reserved for water overflow.

� Risk exposure is higher for the slum population

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CASABLANCA

Coastal erosion risks on the long sea-board� Seaboard characterized by low-

lying beaches, subject to urban encroachment

� Coastline between Casablanca and Mohammedia, beaches east of Mohammedia threatened, as well as Dar Bouazza area

� Sea-level rise expected to worsen coastal erosion by 2030 significantly

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CASABLANCA

Flooding risks� Casablanca’s flood protection

is limited to 20-year recurrence, with some hot-spots of high vulnerability.

� Oued Bouskoura and Oued El Maleh courses through Casablanca and Mohammedialikely to cause worst damages

� Urban encroachments on the Oued Bouskoura cause it to overflow regularly

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CASABLANCA

Tsunami and marine submersion risks� Marine submersion risks

concentrated in the town of Mohammedia, also exposed to flooding.

� Exceptional storm surges can submerge a large portion of the town, expected to increase by 2030 with sea-level rise

� Tsunamic risks are considered low, with a 22% probability over 50 years and 1m waves

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CASABLANCA

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Low seismic risks

CASABLANCA

� Located on a very low gradient slope, the Casablanca area isranked “V” in terms of seismicrisks, with an 8% probability on a 475 recurrence period

� Minor risks of localized landslides

Water scarcity considerations

� Current urban water supply is sufficient thanks to the system of integrated water basins

� Bouregreg basin provides 38% and Oum Er Rabia basin 62% of the water resource for Casablanca

� Demand expected to increase by 1.7 to 1.9% per year to 2030, and CC could cause a fall in supply of the Bouregreg basin of up to 40%

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CASABLANCA

Current institutional preparedness

� Civil Protection system has been recently reorganized with the creation of the Monitoring and Coordination Committee at national scale

� Better preparedness of the emergency response systems is confirmed

� Improved ability to generate timely meteorological alerts

� Management of flooding season from December 2009 to March 2010 positively tested the institutions

� However, Casablanca received a record of 18cm of rainfall on Nov. 30, 2010 which overwhelmed the infrastructure and the preparedness of local response mechanisms

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CASABLANCA

� Potential losses due to natural disasters and clima te change to 2030 = 1.16b DH/year, or 222 DH/year per inhabitant . That is 0.26% of Greater Casablanca’s GDP

� Net Present Value of the cumulated damages and loss es equivalent to 11billion DH, equivalent to 7% of Gre ater Casablanca’s GDP, or $1.39 billion

� Indirect costs are considered to be 20% of the tota l. Flooding damages and losses amount to 94% of the total

� Climate change related losses are estimated at 18 % of the total

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Economic valuation

CASABLANCA

Urban planning responses

� Protection of green areas and waterways to improve urban environmental quality

� Managed retreat of the housing threatened by coastal erosion, greater limits on high-end coastal real-estate projects

� Eco-neighborhoods to be planned for the future urban expansion, with on-site drainage systems

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CASABLANCA

Infrastructure investments required

� A major drainage channel to the West of the city is required to increase flood protection

� Sea dikes will be needed to protect Mohammedia against marine submersion risks

� Coastal erosion protection, water leakages control, water conservation and waste-water reuse systems are all necessary measures

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CASABLANCA

Regulatory, preparedness responses

� Casablanca should increase its level of protection against storm surges and tsunamis with early warning systems

� Integration of data on rapid-onset and slow-onset events should be improved

� Civil society to be more integrated in the preparedness systems at local level

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CASABLANCA

NATURAL RISKS AND CLIMATE CHANGE

� The 2.2m population expected to grow to 3m by 2030, with a 33% increase (lowest of all)

� Urban coverage expected is significantly higher due to demographic transformations

� Multiple risks, becoming higher by 2030, make Tunis the city most at risk among those covered by the study

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TUNIS

A vulnerable urban site in transformation

� The highly sensitive seaboard modifies over time, including the creation of the Gulf of Tunis a few centuries ago

� Many areas area below sea-level, from where drainage water is already being pumped into the sea

� Critical urban infrastructure and neighborhoods are heavily exposed to coastal erosion, flooding, subsidence

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TUNIS

� Ambient temperature average to increase by 1C to 1. 7C, with likely more frequent and longer heat-waves

� Significant reduction in overall rainfall in winter and spring, estimated between 12 and 18 %, is expected

� Despite varying results, there is a high likelihood of an increase of intense rainfall episodes, estimated at 23% over 10 years on the basis of the MET_A1B model downscaling simulati ons

� Such results, consistent with historical trends 196 1-2006, have been adopted in the study on the basis of the preca utionary principle, and reflected in the flood modeling and mapping

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Climate projections to 2030

TUNIS

Coastal erosion

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TUNIS

� Some actions currently being carried out, more portions of the coastline requiring protection

� By 2030, 27 km of urbanized sea-front is considered at high risk, against current 16 km

� Beach retreat could be as high as 15m by 2030. With sea-level rise, beach nourishment is considered insufficient action

Urban flooding a primary risk for Tunis

s

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TUNIS

� Lack of secondary and tertiary drainage systems make Tunis highly vulnerable to flooding

� After 2003 floods, major works have been designed, and are being implemented

� However by 2030 further areas will be subject to flooding, on account of urbanization and climate change impacts

Marine submersion

� Marine submersion risks are already significant across the urban agglomeration

� Areas at higher risk the ones around Sebkha Ariana , shores of South Lake, Rades waterfront, Goulette, and El Khram areas

� By 2030, areas subject to submersion risk may increase by as much as 2,200 hectares

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TUNIS

� Seismic risks for Tunis are classified as “VI” for a 50 year and “VII” for a 475 probability, however the low qualit y of its soils increase the rankings by one degree, making seismic risk high

� Tsunamic risk is considered low, as all studies con ducted show a potential wave of only 0.6m within the Gulf of Tunis. Further studies might revise this risk rating upwar ds

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Seismic and tsunamic risks

TUNIS

Land subsidence risk

� Land subsidence affecting many areas in the agglomeration, in particular in downtown Tunis and shores of South Lake, and the industrial harbor of Rades

� Lands reclaimed in the XIXthcentury and most recently after an environmental clean-up seems the most sensitive ones

� ESA provided satellite earth observation data to study team

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TUNIS

Downtown area of Tunis most threatened

� Multiple risks of flooding, marine inundation, and land subsidence threaten the “Basse Ville” of Tunis

� Risks expected to worsen significantly by 2030

� High economic, social and urban heritage values justify a major effort to rehabilitate this crucial area of the city

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TUNIS

� Many different institutions have responsibility for various aspects of disaster risk management, which is still focused on response rather than prevention.

� Civil Defense Department in the lead, but within a set-up which has not changed for the past 10 years, with ONAS, A NPE, ONPC playing somewhat overlapping roles.

� Limited capabilities to collect and process complex dis aster-related data, and to generate risk maps to be used in prevention. Municipalities have a limited role in risk mgmt.

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Institutional preparedness to disasters

TUNIS

� Potential damages and losses amount to 140m DT/year , or 57 DT/year per person, i.e. 0.29% of Greater Tunis’ GD P per year.

� Net Present Value for the 2010-2030 period equivale nt to 1.5billion DT, which amounts to 8% of the Greater T unis GDP, or $ 1.05 billion

� Potential damages and losses are apportioned: 60% f looding; 26% seismic risks; 14% storm surges and marine inun dation

� Indirect costs are estimated at 40% of the total. T he potential losses directly correlated to climate change are 21 % of total

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Economic valuation

TUNIS

Urban planning responses

� Containing urban sprawl is a critical challenge for 2030, by increasing densities

� Orient future growth away from risk areas and promote eco-neighborhood concept

� Special urban rehabilitation plan for down-town Tunis

� Integrate green areas to mitigate ambient heat

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TUNIS

Infrastructure investments required� Flood protection for down-

town area, the Sebkahs and various urban watersheds

� Coastal erosion control measures between La Marsaand La Goulette, between Radès and Oued Seltene

� Pumping stations for the North and South Lakes required

� Rehabilitation of central areas affected by subsidence

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TUNIS

� Seismic risks to be further addressed with a nation al risk map, a local micro-zoning map taking into account geolog ical data

� Land subsidence and the vulnerability of building s tock to earthquakes should be investigated. Early warning s ystems to earthquakes could be eventually put in place in Tun is

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Improved preparedness, emergency response

TUNIS