Climate change Adaptation and Natural Disasters Preparedness in the Coastal Cities of North Africa Adaptation and Resilience Action Plans for

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1 Climate change Adaptation and Natural Disasters Preparedness in the Coastal Cities of North Africa Adaptation and Resilience Action Plans for Alexandria, Casablanca and Tunis Bonn, June 4, 2011

2 OVERVIEW Broad backing, participation in the study 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 preparation of the Adaptation and Resilience Action Plans, June Support of the Marseille Center for Mediterranean Integration, the Arab Academy for Science,Technology and Maritime Transportation (Egypt), and the European Space Agency. Financial support from Global Facility for Disaster Risk Reduction (GFDRR) and the NTF-PSI,TFESSD trust funds 2

3 OVERVIEW Increasing disasters, climate change impacts 3

4 OVERVIEW Study coverage and methodology Climate downscaling scenarios, probabilistic risk assessments carried out for Alexandria, Casablanca, Tunis, Bouregreg Valley Urban risk assessments for the present time and for 2030, selected as sufficiently relevant to present decision-makers Economic valuation of potential losses and damages showing costs of over $1billion for each of the cities studied, of which 20 to 25% directly due to climate change, to be further refined Adaptation and Resilience Action Plans developed to respond to main risks: seismic and tsunamic, land subsidence, marine submersion, coastal erosion, flooding, and water scarcity 4

5 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 5

6 OVERVIEW Urban risks on the rise in all cities studied 6

7 OVERVIEW No-regret measures, adaptation cost curves The study internalizes the uncertainty related to the climate change projections, emphasizes the need to focus on noregret measures, valid under many scenarios. It also provides decision-makers with adaptation cost-curves 7

8 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 8

9 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 9

10 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 10

11 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 11

12 ALEXANDRIA Steering urban grown away from risk areas 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 12

13 ALEXANDRIA A fragile site historically below sea-level 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 13

14 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 14

15 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 15

16 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 16

17 ALEXANDRIA Marine submersion and coastal erosion risks 17

18 Coastal erosion aggravated by infrastructure The Corniche road, recently built on reclaimed sea-shore, has aggravated storm surges by altering the sea-bed slope 18

19 ALEXANDRIA Urban flooding and water scarcity risks 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 19

20 ALEXANDRIA Limited prevention and response capacities Egypt has suffered from limited ability for natural disasters prevention, and its response capacity has been constrained by a highly centralized decision-making structure The Information and Decision Support Center (IDSC) reporting to the Cabinet, cannot count on significant decentralized response capacities. Recent natural disasters (Sinai flash floods in 2010) show that Government response is inadequate Climate change, questioned until recently by the Egyptian Meteorological Agency, is finally beginning to be recognized as a real challenge, with IDSC and EEAA sharing responsibilities 20

21 ALEXANDRIA Economic valuation of potential damages, losses 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 related impacts are estimated to be about 18% of the total estimated cost. These calculations are however considered preliminary. With respect to climate change related health issues (mostly diarrheal diseases, and malaria), the total annual average costs are around 278 MLE, equivalent to about 0.30% of the city s yearly annual GDP. The indirect costs are estimated at around three times the direct costs. 21

22 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 22

23 ALEXANDRIA Infrastructure investments required Build further sea defenses to limit coastal 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 vulnerability of the housing stock 23

24 ALEXANDRIA Adapting institutions to manage urban risks Strengthening monitoring and early warning systems, in order to better protect the city against extreme weather events Preparation and self-protection against fast-impacting phenomena, via information and education campaigns Insuring against natural risks, via publicly supported schemes that would protect public as well as private investments Improving the capacity to integrate the forecasting of (fastonset) natural risks with (slow-onset) climate change impacts 24

25 CASABLANCA 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 25

26 CASABLANCA Climate downscaling results for 2030 Ambient temperatures increase up to 1.5C Casablanca (pq90) CNRM_A1B MET_A1B MPI_A1B ARPG_A1B ARPG_A2 ARPG_B1 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 26

27 CASABLANCA 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 27

28 CASABLANCA Coastal erosion risks on the long sea-board Seaboard characterized by lowlying 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 28

29 CASABLANCA Flooding risks Casablanca s flood protection is limited to 20-year recurrence, with some hotspots of high vulnerability. Oued Bouskoura and Oued El Maleh courses through Casablanca and Mohammedia likely to cause worst damages Urban encroachments on the Oued Bouskoura cause it to overflow regularly 29

30 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 30

31 CASABLANCA Low seismic risks Located on a very low gradient slope, the Casablanca area is ranked V in terms of seismic risks, with an 8% probability on a 475 recurrence period Minor risks of localized landslides 31

32 CASABLANCA 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% 32

33 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 33

34 CASABLANCA Economic valuation Potential losses due to natural disasters and climate 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 losses equivalent to 11billion DH, equivalent to 7% of Greater Casablanca s GDP, or $1.39 billion Indirect costs are considered to be 20% of the total. Flooding damages and losses amount to 94% of the total Climate change related losses are estimated at 18 % of the total 34

35 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 35

36 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 36

37 CASABLANCA Regulatory, preparedness responses Casablanca should increase its level of protection against storm surges and tsunamis with early warning systems Integration of data on rapidonset and slow-onset events should be improved Civil society to be more integrated in the preparedness systems at local level 37

38 TUNIS 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 38

39 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 39

40 TUNIS Climate projections to 2030 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 simulations Such results, consistent with historical trends , have been adopted in the study on the basis of the precautionary principle, and reflected in the flood modeling and mapping 40

41 TUNIS Coastal erosion 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 With sea-level rise, beach nourishment is considered insufficient action 41

42 TUNIS Urban flooding a primary risk for Tunis Lack of secondary and tertiary drainage systems make Tunis highly vulnerable to flooding s 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 42

43 TUNIS 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 43

44 TUNIS Seismic and tsunamic risks Seismic risks for Tunis are classified as VI for a 50 year and VII for a 475 probability, however the low quality of its soils increase the rankings by one degree, making seismic risk high Tsunamic risk is considered low, as all studies conducted show a potential wave of only 0.6m within the Gulf of Tunis. Further studies might revise this risk rating upwards 44

45 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 XIXth century and most recently after an environmental clean-up seems the most sensitive ones ESA provided satellite earth observation data to study team 45

46 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 46

47 TUNIS Institutional preparedness to disasters 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, ANPE, ONPC playing somewhat overlapping roles. Limited capabilities to collect and process complex disasterrelated data, and to generate risk maps to be used in prevention. Municipalities have a limited role in risk mgmt. 47

48 TUNIS Economic valuation Potential damages and losses amount to 140m DT/year, or 57 DT/year per person, i.e. 0.29% of Greater Tunis GDP per year. Net Present Value for the period equivalent to 1.5billion DT, which amounts to 8% of the Greater Tunis GDP, or $ 1.05 billion Potential damages and losses are apportioned: 60% flooding; 26% seismic risks; 14% storm surges and marine inundation Indirect costs are estimated at 40% of the total. The potential losses directly correlated to climate change are 21% of total 48

49 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 49

50 TUNIS Infrastructure investments required Flood protection for downtown area, the Sebkahs and various urban watersheds Coastal erosion control measures between La Marsa and La Goulette, between Radès and Oued Seltene Pumping stations for the North and South Lakes required Rehabilitation of central areas affected by subsidence 50

51 TUNIS Improved preparedness, emergency response Seismic risks to be further addressed with a national risk map, a local micro-zoning map taking into account geological data Land subsidence and the vulnerability of building stock to earthquakes should be investigated. Early warning systems to earthquakes could be eventually put in place in Tunis 51