North African Coastal Cities - ICCIP the International Climate ...

NORTH AFRICANCOASTAL CITIESAddress Natural Disastersand Climate ChangeTunisBouregreg ValleyCasablancaAlexandriaClimate Change Adaptation andNatural Disasters Preparednessin the Coastal Cities of North AfricaSummary of the Regional StudyJune 2011

A STUDY BUILT ON BROAD BACKING, PARTICIPATIONThe study has been directed by Anthony G. Bigio,Senior Urban Specialist and Lead Author for theIntergovernmental Panel on Climate Change, with aWorld Bank team comprising Stephane Hallegatte,Lead Climate Change Specialist, Salim Rouhana,Junior Professional Officer, Asmita Tiwari andOsama Hamad, Disaster Risk Management Specialists,and Tim Carrington, communications adviser.The study is one of the foundational programs of theMarseille Center for Mediterranean Integration(CMI). Created in 2009, the CMI is a regional knowledgeand learning platform supporting evidencebasedpublic policy choice. Its urban programs supportdialogue, new knowledge and its use among thepublic and decision-makers. The study will providethe basis for future work under the programs.The study benefitted from peer-reviews by the followingspecialists from the World Bank and the GlobalFacility for Disaster Risk Reduction and Recovery(GFDRR): Alex Bakalian, Henrike Brecht, IsabelleForge, Jaafar Friaa, Francis Ghesquière, Philippe Huc,Alex Kremer, Michel Matera, and Edward Tschan.Overall guidance was provided by Anna Bjerde, Urbanand Social Development Sector Manager in the MiddleEast and North Africa region of the World Bank.The study was carried out by a consortium of Frenchconsulting companies headed by Egis-BCEOMInternational, directed by Denis Carra, and includingIAU-RIF and BRGM. Its project team was led by YvesEnnesser, and comprised Michel Abientz, FrançoisBeauchain, François Bertone, Ion Besteliu, DominiqueCataliotti, Jean-Michel Cathala, GuillaumeDulac, Fabrizio Ferrucci, Eric Huybrechts, AzzedineMotia, Mirelle Raymond, Victor Said, Monique Terrier,Mohsen Tounsi, Nadra Tounsi, Terry WinterandFranck Zangelmi. Méteo-Maroc, the nationalmeteorological agency, carried out the detailed climatedown-scaling models, in consultation with theTunisian and Egyptian meteorological agencies.Co-financing partners include the Global Facility forDisaster Risk Reduction and Recovery (GFDRR),the Norwegian Trust Fund Private Sector andInfrastructure (NTF-PSI) and the Trust Fund forEnvironmentally and Socially Sustainable Development(TFESSD), administered by the World Bank.Partners generously providing specific supportinclude the European Space Agency, which providedearth observation via the service companiesAltamira and TRE, and the Arab Academy of Science,Technology and Maritime Transportation,which has collaborated in the Alexandria urban riskassessment.Within the three participating countries, institutionalsupport and technical contributions of the relevantagencies was critical to carrying out the research anddefining the policy responses.In Egypt the Environmental Affairs Agency (CoastalZone Management Department), alongside the AlexandriaGovernorate, has provided support for thestudy.In Morocco, the State Secretary for Water and theEnvironment, the Wilaya of Greater Casablanca, andthe Agency for the Development of the BouregregValley played an equivalent role.In Tunisia, such support came from the Ministry ofEnvironment and Sustainable Development (Environmentand Quality-of-Life Department), the Ministry ofDevelopment and International Cooperation (InfrastructuresDepartment), and the Municipality of Tunis.

OVERVIEW: URBAN COASTAL RISKS ON THE RISENorth Africa’s coastal cities, long benefitting fromtheir ready access to commerce and culture, also facedistinct vulnerabilities due to their location. Naturalhazards and extreme weather patterns impose riskson coastal areas that inland areas seldom encounter.North Africa’s increasingly populous cities facetangible risks today, but these will be amplified asthe impacts of global climate change further manifestthemselves over the decades to come.To better understand both the risks that these citiesface by the 2030 time horizon, and to help preparethe required adaptive responses, the World Bank hasconducted a regional study focused on three citiescritical to the region’s economic, social and politicallife: Alexandria, Casablanca and Tunis. The study alsoexamined the Bouregreg Valley between Rabat andSalé in Morocco, an area which is undergoing largescaleurban development and is slated for furthergrowth in the next decade.The study, “Climate Change Adaptation and NaturalDisasters Preparedness in the Coastal Cities ofNorth Africa,” analyzed the exposure of all four locationsto natural disasters, such as floods and stormsurges, earthquakes and tsunamis, as well as to theincreasingly frequent weather extremes associatedwith climate change. The project, which has takenplace from June 2009 to June 2011, has provided toolsfor evaluating the risks, costing out potential losses,and moving toward specific reforms and investmentsdesigned to adapt the cities to a changing climate andincrease their resilience to natural hazards.Rise in Natural Disasters Already inEvidenceAlready, the southern Mediterranean and MiddleEast have seen a measurable rise in natural disasters.From an average of three natural disasters a year in1980, the region experienced a steady increase to anaverage of more than 15 in 2006. All told, the regionwas been hit by 276 disasters in this 25-year timeperiod, of which 120 occurred in the last five years. Byany measure, the risks associated with natural catastrophesare on the rise, also on account of increasingpopulation and assets exposure.Urban Risks Increase Over Time in All Urban Locations under the StudyUrban Risks Alexandria Tunis Casablanca Bouregreg ValleyHorizon Current 2030 Current 2030 Current 2030 Current 2030Seismicity/ground instabilityTsunami/Marine submersionCoastal ErosionFloodingWater ScarcityVery High High Medium Low Very LowNORTH AFRICAN COASTAL CITIES ADDRESS NATURAL DISASTERS AND CLIMATE CHANGE | 1

2 | OVERVIEW: URBAN COASTAL RISKS ON THE RISEIn North Africa’s coastal cities, urban managers, businessesand households have had to cope with numerouscostly and destructive episodes of extreme weather.Recent extreme weather eventsOn November 30, 2010, Casablanca was deluged bya record 18 centimeters of rain overnight— equal toabout six months of rainfall under normal patterns.The resulting floods forced the shutdown of variousfacilities, including the international airport, businessesand schools throughout the city. Companieslost inventories. Streets became swirling rivers,with cars mostly submerged, and citizens strugglingthrough waist-high water to reach places of security.More than 2,500 families had to be accommodatedin various public structures. After the disaster, citycouncilors called for an urgent review of infrastructures,services, and institutional systems implicatedin emergency response.3025On December 10–12, 2010, heavy rains, storm surgesand strong winds hit Alexandria, causing the partialcollapse of 28 buildings, with 18 people dying in thecatastrophe and dozens more injured. Streets wereinundated, harbor activities suspended. A factory collapsedon a group of workers after the rains damagedthe structure.For Tunis, the scope of natural disaster risks hit homein September, 2003, when a particularly severe stormswept the coastal city. In a 24-hour period, Tunis tookin about five times the volume of rain as typically fellin the entire month of September. The catastrophedamaged buildings, cost lives, and overwhelmed thelimited drainage systems of the city. Following thedisaster, the Tunis authorities analyzed weak pointsin urban structures and initiated studies and investmentsto help the city withstand similar catastrophesin the future.Risks Likely to Increase Over TimeTwo trends confirm that the cities will be increasinglyvulnerable to flooding and other natural disastersover the next two decades:Climate change, whose future magnitude andimpacts necessarily remain somewhat uncertain,adds to the frequency and intensity of extremeweather events, so that historical patterns nolonger function as indicators of future weatherrelatedrisks. According to the InternationalPanel on Climate Change, North Africa is thesecond most vulnerable area in the world toemerging climate-related risks.201510501980198219841986198819901992Year1994199619982000200220042006Number of disasters 3 per. Mov. Avg.Natural disasters affecting Middle Eastern (number and North of disasters) African countrieshave increased significantly since 1980. (Source: EMDAT)Rapid urban population growth throughoutthe Middle East and North Africa raises thestakes by increasing the potential losses fromnatural disasters and climate-related damages.Some 60 million people inhabited the region’scoastal cities in 2010, but the number is expectedto swell to 100 million in 2030, placing morepeople, livelihoods and structures at risk. Alexandria,Casablanca and Tunis—home to about tenmillion people in 2010—can expect a combinedpopulation of around 15 million in 2030. TheBouregreg Valley anticipates an influx of up to140,000 people in an area that has remainedvirtually uninhabited for centuries.

NORTH AFRICAN COASTAL CITIES ADDRESS NATURAL DISASTERS AND CLIMATE CHANGE | 3Sea level change (mm)5004003002001000–100–200Estimates ofthe pastInstrumental record1800 1850 1900 1950 2000 2050 2100YearUrban Risk AssessmentsProjections ofthe futureProjections for the 21st century carry uncertainty, but even at the lowend of the range, sea level rise will compound current risks for NorthAfrican coastal cities. (Source: WRI)The study took into account climate change projections,urbanization and demographic shifts, andexamined coastlines, structures, and neighborhoodsthat will face increasing risks. Looking at specificthreats, such as flooding or coastal erosion, the studyteam found that most risks increase over the 2010–2030 period. Sea level rise—a critical climate-changerisk for coastal cities—is an important unknown butis assumed in the study to be 20 cm by the year 2030.The higher seas would compound storm surges,increasing the risks for marine inundation and coastalerosion.The report has identified specific risks within each ofthe four urban areas, and proposed adaptive actionsthat would mitigate potential damages and losses.Risks have been quantified, along with the costs ofadaptive and climate-resilient actions, so that plannerscan calculate the costs and benefits associatedwith the particular courses of action recommended.Although the study focuses on four specific locationsonly, the analytical processes it employs are relevantto many other coastal cities in the region.Economic valuationsThe study found that over the 2010–2030 period, thethree cities each face potential cumulative lossesof well over $1 billion from the risks, which includefloods, earthquakes, coastal erosion, ground instability,marine inundation, tsunamis and water scarcity.Meanwhile, the planned development of Morocco’sBouregreg Valley could place communities, housesand industries at risk—unless the project follows apath of climate-smart development.The bulk of the risks are related to natural disastersto which the coastal cities are already vulnerable,Days92847667595042342517860 hours64 hours86 hours1950 1954 1958 1962 1966 1970 1974 1978 1982 1986 1990 1994 1998 2002 2006Heat waves are becoming longer lasting, with higher peak temperatures, as this record for Tunis shows, increasing impacts on public health, includingmore respiratory diseases.

4 | OVERVIEW: URBAN COASTAL RISKS ON THE RISEbut by 2030, about 20% of the potential losseswould be attributable to various impacts of climatechange. Given that by all scientific accounts climatechange manifestations are going to increase significantlyby mid-century and further, it is very likelythat a much greater percentage of losses will beattributed to climate change for the 2050 or 2070scenarios.Lessening the Risk: Overlapping Spheres of ActionInfrastructureUrbanPlanningInstitutionalActing to Make Cities Resilient,Adapted to Climate ChangeThe study’s first phase focused on future climate projections,probabilistic risk assessments, and hazardand exposure measurements, leading to the formulationof current and future urban risk assessments. Thesecond phase has generated Adaptation and ResilienceAction Plans that would make all three cities,and the Bouregreg Valley, more resilient to naturaldisasters and better adapted climate change impacts.Lessening the risks requires actions in three overlappingspheres: urban planning initiatives; institutionalreforms and capacity building; and strengtheninginfrastructure.Urban design plans will have to take intoaccount the risks of placing communities orenterprises in low-lying and risk-prone areas, andprovide climate-appropriate solutions for futureurban expansions.Institutions will need to function at higherlevels of efficiency and coordination to preventand lessen damages, with improved early warningsystems, effective communications, and clearlines of responsibility.Urban infrastructure such as coastal defensesand drainage systems will require upgrading andreinforcement.These three areas of adaptation and resilience are oftenoverlapping and mutually reinforcing, and have to9214133210Lutte contre les submersionsmarines (TM3) –zone de Mohammedia192 MDHSystème d’alerte et de prévention3,132 MDHInondations: mesures à la parcelle1,399 MDHLute contre lessubmersions marines (TM3):zones hors Mohammedia229 MDHInondations: mesurescollectives5,435 MDH Mesures anti-érosion:TM1/S1283 MDH Mesures anti-érosion:TM1/S1261 MDHAdaptation cost curves, like this one for Casablanca, allow cities to weigh the benefits of measures proposed within the action plans. The verticalcolumn shows the ratio of benefits-to-costs for investments in specific processes, institutions, and infrastructures. The horizontal red line shows thebreak-even point, above which benefits, under current conditions, outweigh costs.

NORTH AFRICAN COASTAL CITIES ADDRESS NATURAL DISASTERS AND CLIMATE CHANGE | 5be managed and implementedsimultaneously.Action plans drawn up inpartnership with local officialsin the three countries haveset the foundation for policyresponses and investments tolimit current and future urbanvulnerability. Economic evaluationscan assist decisionmakersin weighing the costsand benefits of particularpreventive actions, after factoringin the potential lossesin taking no actions.Tools for ReducingUncertaintiesOn this basis the study hasgenerated “adaptation costcurves” which rank the costeffectiveness of each remedialmeasure proposed. Many of such measures pass thecost-benefit test and are confirmed to be economicallyeffective and promise to deliver high returnsin terms of risk reduction. In particular, all “soft”measures, such as urban planning and strengtheningthe institutional preparedness, offer a high returnon investment. Some of the infrastructure measuresproposed turn out to be more costly than the damagesthat would be off-set, but can still be justified interms of the intangible values of some urban locations,for instance on heritage grounds.The study reduces the scope of uncertainty facing decision-makerswith regard to future climate and urbanrisks, but it cannot eliminate it entirely, given that thelocal impacts of climate change will be greatly affectedby the scope of the worldwide mitigation measuresImproved early warning systems help coastal cities lower potential damages from sea surges, stormsand tsunamis. Systems of “smart buoys” linked to satellites, such as this one proposed for Alexandria,offer real-time surveillance and greater preparedness.Les installations peuvent être fixes ou mobiles, déployées dans les lieux sensibles ou transportables etinstallées sur des zones variables lors des alertes.reducing greenhouse gas emissions over the next twodecades. The most effective responses, therefore, takethe form of so-called “no-regret” actions, which aresensible and cost-effective under a variety of futureclimate scenarios. Of course, Adaptation and ResilienceAction Plans should be updated periodically torespond to further findings and evolving scenarios.Moving Towards ImplementationWith the study completed, the tasks ahead involvecreating political consensus and mobilizing financialresources for the most critical planning and policyinitiatives and investments, so that these cities, whichhave historically contributed so profoundly to theidentity of the region, may be better prepared to facethe challenges of the future.

ALEXANDRIASTEERING URBAN GROWTH AWAY FROM AREAS AT RISKThe ancient city of Alexandria is home to a populationof 4.1 million, with an expectation of 6.8 millioninhabitants by the year 2030, a surge of 65%. Theoriginal city, built by Alexander the Great in 331 BC,has grown enormously over the centuries with steadyexpansions along its water front. From the coastalvillage of Abu Quir in the northeast to the village ofEl-Deir in the southwest, the Alexandria agglomerationconsists mainly of high-density settlementsalong a partially elevated ridge facing the sea, backedby low-lying rural areas containing a number of lakesand wetlands. Many of these areas fall below sea leveland are also highly vulnerable to flooding, which iscontrolled by pumping stations ejecting water intothe Mediterranean Sea.Urban Risks Increase Over Time in All Urban Locationsunder the StudyUrban RisksAlexandriaHorizon Current 2030Seismicity/ground instability/Tsunami/Marine submersionCoastal ErosionFloodingWater ScarcityHigh Medium LowPatterns of Urban GrowthIt is expected that Alexandria’s expansion will tendto take place westward, along the Al-Bouhayra Lake,with further urban sprawl towards the south. Poorercommunities are likely to increase along certainshoreline areas, in the Abu Quir depression and nearthe Maryut Lake. Other areas likely to house futurepopulation growth are in low-lying spaces subject toground subsidence and increasing climate-relatedrisks. Expansion south of the Al Montaza and Sharqareas is likely to increase the number of people andvalue of structures exposed to seismic and floodingrisks.The city’s recent reconstruction of its sea-front roadwayin the form of a ten-lane coastal highway hasintensified already evident patterns of coastal erosionand storm surges, by steepening of the slope ofthe seabed. As a result of future sea-level rise, suchevents are likely to have further impact into the city’sbuilt front, exposing new areas to risk.Key RisksOne element of Alexandria’s critical exposure to risksare its informal settlements, which currently houseone third of the city’s total population, and whichare likely to increase with population growth. More

8 | ALEXANDRIA: STEERING URBAN GROWTH AWAY FROM AREAS AT RISKThis multi-risk map of Alexandriahighlights critical vulnerabilities.The large shaded area indicateslow-lying, flood-prone lands;red represents high-densityresidential areas; yellow showsslums and informal settlements;blue shows areas most subject tomarine submersion. The diagonalline off the coast representsdifferent degrees of coastalerosion risk.Flooding: Vulnerabilities are evident in recentlyurbanized areas that are below sea level, includingan area between the hydro-dome and AbuQuir, at the edge of the former Abu Quir lagoon,and in the Sharq and Al Montaza districts. Withoutcareful planning for the use of areas belowsea-level, informal settlements will multiply, andwith more frequent and more intense extremerainfalls, flooding will escalate to a medium riskin 2030 from a low risk in 2010.Seismic threats and ground instability:Northern Egypt faces moderate earthquake andseismic risks. However, subsidence combinedwith increasing informal settlements raise thepotential losses from structural damage, increasingthe rating to a medium risk in 2030 from alow risk in 2010.Tsunami and marine submersion: Seafrontbuildings along the densely urbanized coastlineare exposed to structural damages, while low-lyingareas risk marine submersion. Coastal areasnear Abu Quir are directly threatened by marinesubmersion, with specific worries that the 18thcentury Mohammed Ali sea wall could rupture incase of a major earthquake or tsunami, puttingareas below sea-level at risk of inundation. Withincreased settlement of the shoreline, along witha likely expansion of residential developmentsover current natural areas, such threats rise tothe high-risk category by 2030, up from a mediumrisk in 2010.Coastal erosion: Over time, Alexandria’sbeaches have been receding, with increasingrisk of structural damage to shoreline buildings.There are significant erosion risks betweenEl Dekhiela Harbor and the western harbor of

NORTH AFRICAN COASTAL CITIES ADDRESS NATURAL DISASTERS AND CLIMATE CHANGE | 9Alexandria, and at Abu Quir. With the higher sealevels associated with climate change, coastalerosion and the beaches retreat are likely to accelerate.As a result, erosion rises to a high-riskcategory in 2030, from a medium-risk in 2010.Water resources scarcity: With Egypt’sgrowing population and a constantly increasingindustrial demand for limited Nile water, waterscarcity problems are likely to occur. Waterdemand surged by 50% over the past decade,and with nearly half of Egypt’s industrial activitycentered in Alexandria, urban demand for limitedwater resources is certain to grow. Meanwhile,local aquifers are becoming exhausted and aresubject to salinization. Unmediated competitionfor Nile resources with upstream countries couldexacerbate shortages, so that by 2030, the city’scurrent supply from the Nile could become insufficient,and water resources scarcity is rated as ahigh risk in the future from a low risk today.For Alexandria, the cumulative potential damagefrom natural disasters and climate change impactsis estimated to be $1.72 billion in Net PresentValue for the period 2010–2030. An estimated18% of that total is attributable to climate changeimpacts alone.Adaptation and Resilience ResponsesThere is much that decision-makers can do to protectthe well-being of the city’s population and lessen thepotential harms to the economy of natural disastersand climate change. Broadly, the study encouragesEgyptian policymakers to shift from mainly respondingto natural disasters and weather events after theyoccur to focusing on preventive actions to limit thedamage natural disaster might cause and to prepar-Alexandria’s building stock mostlyconsists of older and low-qualitystructures vulnerable to naturaldisasters, represented by red andmagenta in the map. Patterns ofhigh-density occupancy in theseareas multiply the vulnerabilities.(Source: GOPP)

10 | ALEXANDRIA: STEERING URBAN GROWTH AWAY FROM AREAS AT RISKing for the progressive impacts of climate change. Thestudy also provides tools for pricing the costs of variousactions, comparing these costs to damages thatmight occur if no adaptive actions are taken.Urban PlanningAdequate urban planning and land-use policies willbe critical to limiting the Alexandria’s exposure torisks, damages and losses. The 2030 Greater AlexandriaMaster Plan, currently being prepared, is anexcellent opportunity to incorporate the results of thestudy’s urban risk assessment, and to re-orient thecity’s future expansion away from the areas identifiedas most at risk. The Master Plan should also directfuture urban growth, define city limits, and establisha land-use program with rules for densities, buildingheights and open space ratios taking into accountfuture climate scenarios.Institutional PreparednessUpgrading early warning systems covering all typesof disasters emerges as a particularly sound investment.Improved management of coastal areas alsoemerges as critical. For example, a system of “smartbuoys” along the coastline could help generate timelydata that could help protect people and propertyfrom coastal storm surges. Improved communicationamong agencies involved in disaster prevention andresponse could strengthen timeliness and coordination,leading to more robust responses.Infrastructure InvestmentsInvestments in making existing structures more resilientwould benefit coastal marine defenses. Some keyurban infrastructures and buildings, along with watersupply and drainage systems, could be made morerobust and better able to withstand the damages thatcan occur in storms such as the one that hit Alexandriain 2010. Like other cities, Alexandria can lowerflood-related risks by taking steps to improve controlof runoff and discharge sources, and routine maintenanceof the sewage system all would lower risksduring flooding periods. In addition, areas slated fordevelopment can be sited and prepared to minimizethe vulnerability. Investment in special equipment—such as mobile water pumps—can help with drainageproblems during flooding.

CASABLANCACONFRONTING FLOODING, COASTAL EROSION ANDMARINE SUBMERSIONCasablanca is home to 3.3 million people, withanother 300,000 in nearby rural areas. In the period1994–2004, the population surged by more than halfa million. According to estimates based on historicalpatterns, the population of Greater Casablanca willswell by 55% to 5.1 million by 2030.Patterns of Urban GrowthEconomic expansion and population growth willcontinue to fuel a sharp rise in the number of households.As a result, the urban area is expected to expandby as much as 1,000 hectares a year. Significanturban development is also expected to occur alongthe Casablanca waterfront and in low-lying areas thatare vulnerable to sea storm surges and flooding.Key RisksCasablanca is particularly vulnerable to flooding,coastal erosion and marine inundation, and is experiencingsignificant pressures linked to rapid urbangrowth. The city also houses many precarious structures,some older and poorly maintained, some newerand poorly constructed. A number of the slums anddensely populated neighborhoods are located in lowlyingneighborhoods, and have encroached on areaslegally protected for water catchment.Morocco has experienced climatic shifts in recentyears, including warmer average temperatures andoverall decreased yearly rainfall. Projections for 2030envision warming for Casablanca of up to 1.3 degreescentigrade, with annual rainfall accumulation decreasingby 6% to 20%. However, it is also expected that thewarmer temperatures and lower levels of annual rainfallwill be accompanied by more frequent and moreintense episodes of extreme precipitation, furtheroverwhelming the already stressed urban drainagesystems.The town of Mohammedia, subject to devastatingfloods in 2002, requires special attention. An analysisUrban Risks Increase Over Time in All Urban Locationsunder the StudyUrban RisksCasablancaHorizon Current 2030Seismicity/ground instability/Tsunami/Marine submersionCoastal ErosionFloodingWater ScarcityHigh Medium Low Very Low

12 | CASABLANCA: CONFRONTING FLOODING, COASTAL EROSION AND MARINE SUBMERSIONof the vulnerabilities and structural fragilities underscoredthe need for improved drainage facilities andgreater physical protection against sea surges.Morocco’s Disaster Risk Management has becomesignificantly more effective as a result of changescarried out since early 2009. A restructured GeneralDirectorate of Civil Defense and a new Supervision& Coordination Committee have generated positivereviews from a mix of stakeholders. Improved disasterpreparedness and more accurate warnings fromthe Department of Meteorology, Morocco enableda much improved response to torrential rains andflooding between December 2009 and March 2010.Urban Risk AssessmentFollowing are the key results of the risk assessmentsfor Casablanca, as measured in 2010 and forecasted for2030:Flooding: Casablanca has been regularly disruptedby floods, given its current level of protection,limited to a level of rainfall recurring everyfive years. This is due to insufficient city-widedrainage systems and the informal urbanizationof catchment areas. The study has identified specificareas of Greater Casablanca that are particularlyvulnerable to periodic flooding: slums andstructures built with cheap or inferior materialsare of particular concern. Flooding is considereda high risk in 2010, and will remain high for the2030 scenario.Tsunamis and marine submersion: ForCasablanca, the risks posed by tsunamis andmarine submersion are considered medium,given the historical record of relatively recenttsunamic events, and are expected to remain soby 2030. Marine submersion risk is significant forspecific segments of the coastline, in particularfor Mohammedia, where storm surges can causeAreas of substandard dwellings,indicated by red, constitute 28%of all housing stock, with 11%categorized as slums. Theseextend across Greater Casablanca,but are concentrated in thenortheast outskirts. Black squares(not drawn to scale) indicate thesize of slum areas.

NORTH AFRICAN COASTAL CITIES ADDRESS NATURAL DISASTERS AND CLIMATE CHANGE | 13Flood-prone areas, indicatedby the dark blue, are sprinkledthroughout residential,industrial and mixed-used partsof Greater Casablanca. The mostcritical areas are the town ofMohammedia and the courseof the Oued Bouskoura cuttingacross the city to the harbor.Already planned infrastructureimprovements are expected toreduce exposure to flooding.the inflow of sea-water inland with severe consequencesfor the productive and administrativecenter of the city. Storms, intensified by highersea levels, will be likely to damage the city’ssea-front and put more areas at risk of marinesubmersion. The low-lying areas near the outletsof the main ephemeral streams of Mehla andNfifich face distinct risks.Coastal erosion: A ten-kilometer coastal segmentstretching between the eastern endof Casablanca and the Mohammedia powerstation now faces a strong risk of erosion, withanother thirty to forty kilometers of coastlinesegments also considered at risk. Expectedsea level rise intensifies such vulnerabilitiesin the future. The risks of coastal erosion willincrease, with sand beaches expected to retreatby as much as 15 meters by 2030. Erosion risk isranked as high risk today as well as for the 2030scenario.Water resources scarcity: Water insecurity,ranked as a low risk in 2010, would become a mediumrisk by 2030, assuming current estimatesof population and industrial growth. This is inrelation to the overall decrease in rainfall whichthe country is expecting, with the consequentdecrease in resource and additional pressureover the apportioning of water for urban andrural usages.The potential aggregate economic losses for the2010–2030 period due to natural disasters andimpacts of climate change in Casablanca wouldhave a Net Present Value of $1.39 billion, the bulkof which is associated to flooding. Such losseswould be commensurate to losing 7% of the grossdomestic product of Greater Casablanca. Potentialeconomic losses attributable to climate changeimpacts would represent an estimated 18% of thetotal.

14 | CASABLANCA: CONFRONTING FLOODING, COASTAL EROSION AND MARINE SUBMERSIONAll along the Casablancaseaboard, low-lying areas suchas the town of Mohammedia,are subject to high marinesubmersion risks. Blue areasindicate present risks, red areas,additional exposures coming onby 2030.Adaptation and Resilience ResponsesThe study calls for an integrated approach for the detailedland use planning and urban design of Casablanca’sneighborhoods, reconciling the expected growthof population and economic activities with environmentalconsiderations. This approach has already beenembraced by the 2030 Master Plan which was recentlyapproved, and now needs to be applied in greater detailas the zoning plans are being designed. Climate-relatedvulnerabilities and natural risks have to be factored inwhen the city considers potential uses of vacant land oridentifies areas for new housing construction. Floodproneareas should be carefully screened to avoidworsening inundation and drainage problems.Urban PlanningThe study also suggests the creation of eco-neighborhoodsto demonstrate approaches to environmentallysustainable, climate-resilient design and construction,which could serve as models for new development inCasablanca and beyond. Meanwhile, areas subjectedto repeated flooding would undergo detailed plansto protect key structures and buildings. It is expectedthat slums would eventually be redeveloped underthe national slum up-grading program, and that otherovercrowded areas would undergo rehabilitation.Institutional PreparednessMoroccan institutions can take specific actions tobecome more effective in responding to naturaldisasters. Risk factors are already incorporated inthe organizational and regulatory framework, but thecountry would benefit from further steps to removeoverlapping ministerial functions, to simplify operations,and to separate civil defense and the roles ofstate and local institutions.Casablanca also needs new information systems,including improved strategies to alert citizens and enterprisesof rapidly changing weather conditions, alongwith plans for protecting lives and property. The studyhas strongly recommended upgraded systems for surveillanceand early warning, with greater use of satellite

NORTH AFRICAN COASTAL CITIES ADDRESS NATURAL DISASTERS AND CLIMATE CHANGE | 15imagery and regular measurement of land subsidence,temperature changes and shifts in water levels.Infrastructure InvestmentsThe studies attach special urgency to addressingphysical vulnerabilities along the coastline, particularlythe stretch of about 40 kilometers that is alreadysubject to erosion and sea storm surges. A vulnerablecoastal span between Mohammedia, and Casablanca,where protective dunes are considered particularlyfragile, could benefit from steps to reinforce thenatural barriers, coupled with the managed retreat ofsome illegal coastal housing.Casablanca would also benefit from improvementsin the drainage system to ensure its viability duringflooding crises, along with expanded infrastructurefor accommodating runoff and drainage. A criticalflood prevention project is the construction ofthe drainage canal dubbed “Super Collector West”,which has already been designed and quantified, andwhich would increase the flood protection of the cityto a 20-year level. This infrastructure would drain anumber of basins that tend to overflow during heavyrainfall and potential floods in the western part ofthe city.New dam structures would be necessary to assurelong-term protection of communities and propertyagainst the sea. Casablanca should also extend thecurrent programs aimed at reducing water leakages,favor water conservation, and link water storage facilitiesinto an integrated system that would include enablethe use of harvested rainwater for watering greenareas.

TUNISADDRESSING MULTIPLE RISKS, ONSET OF CLIMATE CHANGEResidents of Tunis expect hot, dry summers followedby mild, wet winters. But they also have cometo anticipate weather extremes. Following a series adamaging storms over thirty years, Tunis encountereda devastating storm in 2003, with major floodingacross the city, and losses amounting to hundreds ofmillions of dollars. That same year, the city experienceone of the most intense heat-waves on record. Thecity drew up new disaster response plans and initiatedinfrastructure improvements. But with climatechange, extreme episodes as occurred in 2003 areexpected to become more frequent, requiring a freshlook at the city’s level of preparedness.Patterns of Urban GrowthPopulation growth in Tunis is more modest than inother cities in the region, but still a significant factor inassessing future risks. The urban population of 2.25 millionis expected to increase 33% to about 3 million by2030. However, the tectonics and soils of the city itselfpresent profound challenges. In downtown Tunis, landsubsidence leaves some buildings tilting visibly to oneside, and seismic risks are considerable. The coastlineis seriously threatened by erosion, requiring reinforcedbeach defenses. The coastline itself is continuouslyshifting despite sea defenses and beach nourishmentwhich have been built and implemented regularly.Key RisksUrban Risks Increase Over Time in All Urban Locationsunder the StudyUrban RisksTunisHorizon Current 2030Seismicity/ground instability/Tsunami/Marine submersionCoastal ErosionFloodingWater ScarcityVery High High Medium LowTopographical data shows that urbanized and industrialareas in the lower downtown, Rades, Ezzahra andHammam Lif Ouest are vulnerable to marine submersionunder certain storm conditions. Extreme rainfallevents could increase by 25% under widely acceptedscenarios for climate change by 2030. Tunis couldbe facing the occurrence of 50- year weather eventsthat formerly occurred once every one hundred years.Similarly, intense rains that might once have comeevery fifty years could arrive once every twenty in thenear future. The return period for less violent weatherepisodes would be telescoped in the same way.

NORTH AFRICAN COASTAL CITIES ADDRESS NATURAL DISASTERS AND CLIMATE CHANGE | 17Institutional strengthening can help better managethe risks. The National Office for Civil Protection leadsvarious agencies in the prevention and managementof disasters, but the structure of this arm of governmenthas barely changed over the decades. Pastepisodes of natural disasters haven’t been followed byassessments and regulatory or operational improvements.Cartographic information and geographicaldata bases remain largely absent, along with textscovering specific risks.Urban Risk AssessmentFollowing are the key results of the risk assessmentsfor Tunis, as measured in 2010 and forecasted for2030:Flooding: Floods, a recent and major problemfor the city, would likely intensify, rising froma current high risk to a very high risk by 2030,despite the full implementation of the trunkdrainage system upgrades under way, on accountof the likely 25 percent increase in extremeprecipitation events, which can generate floodlevels of more than one meter in certain areas ofthe city Certain drainage basins will face a severerisk of flooding, exacerbated by inadequate localdrainage and rapid urbanization. Meanwhile, asthe city expands, new construction on hillsidesand in flood-prone areas could be adding torunoff volumes and consequent damages, unlessplanned in a climate-appropriate way.Coastal erosion: Erosion, already a high riskalong the Tunis shoreline in 2010, is ranked asa very high risk by 2030. The coastline of theGulf of Tunis has been receding for half a century,despite offshore protections mitigating thetrend. In some stretches of the coastline it canrecede by as much as 10 meters a year. By 2030,27 kilometers of the urbanized seafront wouldbe considered at a high risk of erosion, up from16 kilometers in 2010. Sea level rises projectedunder climate change would accelerate coastalerosion, with beaches receding by as much asIn economically important central Tunis, subsidence indicatedin red combines with flooding risks indicated in blue to multiplypotential impacts. Major storms overwhelm the center-city drainage,inundating streets and buildings.15 meters by 2030. The coastline between KalaatLandalous and Raoued Beach could be severelyeroded by 2030.Tsunamis and marine submersion: Thestudy assumes a global sea level rise of 20 centimetersby 2030, which could intensify the damageto sea barriers, raising the risk of submersionsfor the city. By 2030, the study estimatesthat an expanded stretch of the urban seafrontwould be at a high risk of submersion. Taken together,the risks rise from a medium-risk categoryto high-risk by 2030.

18 | TUNIS: ADDRESSING MULTIPLE RISKS, ONSET OF CLIMATE CHANGEEarthquake and ground instability: Tunisfaces in general a moderate earthquake risk, buton account of the poor geotechnical quality ofTunis’ soils, the damage risks would be considerablyhigher. Subsidence in the downtown areapresents distinct challenges to the neighborhoodsbuilt on land reclaimed from the Lake ofTunis during the French colonial period, rich witharchitecture which is part of the cultural patrimonyof the city According to the study, the relatedrisks increase from medium to high between nowand 2030.Water scarcity: Water demand will increase inTunis, on account of a bigger, wealthier populationby 2030, simultaneously with an expectedconsiderable drop in average rainfall at thenational scale. Despite excellent water resourcemanagement at the national level, urban usagewill place more strains on the resource, with theresult that water scarcity rises to a medium riskin 2030, from a low risk in 2010.The likely aggregate economic losses from allthe risks amount to a Net Present Value of $1.05billion, or 8% of the urban economy of the capitalcity. About 59% of the potential losses relateto submersion risks, with 26% reflecting seismicrisks and 14% from storm surges. An estimated25% of the potential losses by 2030 would be attributableto climate change, with most involvingflooding.Adaptation and Resilience ResponsesOverall, climate-resilient urban planning will be crucialfor Tunis to manage the risks caused by naturalhazards and climate change. Areas of the city that arelow-lying and subject to flooding will require furtherupgrading of drainage systems before further developmentis allowed. Illegal housing development at theBy 2030, factoring in climate change and sea level rise, significantstretches of the Greater Tunis seaboard, indicated in darker shading,could be submerged during mega-storms likely to occur every hundredyears.periphery will need to be contained, in line with therecommendations of the Master Plan. Careful zoning,with allowance for green spaces, along with rigorousenforcement of standards, will be critical.

Figure 23 : Zone 2 - Lac de Tunis et partie Nord-Est de la Sebkha Sejoumi (Source : TRE2010)NORTH AFRICAN COASTAL CITIES ADDRESS NATURAL DISASTERS AND CLIMATE CHANGE | 19Urban PlanningZoning decisions would also factor in the city’s significantsubsidence problems, which undermine its resilienceto storms, seismic risks and extreme weather.Future developments will have to be designed so asto minimize additional loads to runoff, by providingfor on-site absorption of rain-water via green roofs,rainwater storage and other environmental devices.Institutional PreparednessBecause of the potential damage from earthquakes,sea surges and tsunamis, the study recommends thata system of monitoring and early warning, coupledwith communications plans for alerting citizens andenterprises, be installed. For the most exposed areas,sirens and other emergency systems would be necessary.Concurrently, the city should begin to assess indetail the vulnerability of existing buildings to thevarious risks so that specific actions may be carriedout to increase their resilience. Some areas will likelyrequire an urban requalification strategy.Tunis also needs monitoring systems to track theretreat of beaches and threats to its coastal barriers.Modern air-based surveillance can provide valuablecontributions in such systems. The city will need aspecific plan for reversing already observed erosionin the vicinity of Rades, and in certain other areas.The study advanced a series of specific recommendationsfor other stretches of coastline that havebeen degraded over time, by storms and changes inthe coastal profile. Overall, Tunis would also benefitfrom a better legal framework for the management ofcoastal zones.Infrastructure InvestmentsInfrastructure strengthening will be critical in certainareas. Sewerage and drainage structures in Tuniswill require upgrading, within an overarching masterplan. Better equipment to manage water levels at thelake and harbor will be necessary and in some areas,dikes will be the required part of the solution. Tuniswill also need to invest in reinforcing existing drainageand sewage systems so that they can manage themore frequent extreme weather events. To addressincreasing pressures on limited water resources, asystem for optimizing water uses and better managingconsumption will be needed, including revised pricingpolicies.Central Tunis, former and presentindustrial areas on the southernshore of the lake and the portof Rades have experiencedsignificant subsidenceas measured via satelliteobservation, raising risk levels.Source: ESA.

THE BOUREGREG VALLEYINCORPORATING RISK REDUCTION IN THE PLANNINGClimate-smart planning is particularly relevant in thecase of the Bouregreg Valley, since it is possible tomitigate many of the risks affecting the site beforeinfrastructures are built and buildings erected. Broadly,the project is a high-end development of a quasi-virginsite, and therefore it is entirely possible to expect thata high level of protection be built into its plans fromthe start. The planned development envisions about140,000 inhabitants and 90,000 new jobs—all to belocated in an area vulnerable to natural disasters andclimate-related risks. The project site is located atthe estuary of the Bouregreg River, with a major dambehind it, the open sea in front, and two steep slopeson either side.With some settlements planned for the mouth of theriver, and other areas slated for construction currentlyvulnerable to flooding and landslides, the developmentcould end up putting more people and assets atrisk. However, the opportunity to adopt climate-resilientland-use policies and building designs creates theprospect of mitigating the risks significantly as part ofthe planning process.Urban Risk AssessmentFollowing are the risk assessments for the BouregregValley for the current, pre-project scenario, as well asfor the 2030 scenario:Urban Risks Increase Over Time in All Urban Locationsunder the StudyUrban RisksBouregreg ValleyHorizon Current 2030Seismicity/ground instability/Tsunami/Marine submersionCoastal ErosionFloodingWater ScarcityVery High High Medium LowFlooding: The Bouregreg Valley has been aflood-prone valley since time immemorial, andconsequently has remained practically undeveloped.Since the construction of the Sidi MoulayBen Abdellah dam, water flows are regulatedand controlled, including at times when the damcapacity is attained and large volumes of waterhave to be released downstream. This currentlyhappens with little hindrance to people or assets,but could become a major problem given on oneside the expected increase in the frequency andintensity of extreme weather events, and on theother the land-use and construction plans for theValley. The related risk rating would jump fromthe current low to very high for the 2030 scenario.

NORTH AFRICAN COASTAL CITIES ADDRESS NATURAL DISASTERS AND CLIMATE CHANGE | 21The Bouregreg Valley project,as envisioned in this map,represents one of the mostsubstantial developments inNorth Africa, with 140,000 newinhabitants and 90,000 jobsexpected in a site with highnatural risks.Tsunamis and marine submersion: Tsunamicepisodes have hit the Moroccan coastline inrelatively recent times, however this risk is consideredcurrently as medium on account of thelow level of population and assets in the Valley.The same applies to marine submersion relatedto storm surges. Such risks become high by 2030on account of the implementation of the projectitself.Coastal erosion: Current risks, rated medium,would be lessened to low by 2030, on account ofthe measures which have already been integratedinto the development plan, and which includethe construction of sea defences against beachand coastal erosion.Seismic risk and ground instability: Twoissues affect the Bouregreg Valley: on one hand

22 | THE BOUREGREG VALLEY: INCORPORATING RISK REDUCTION IN THE PLANNINGthe low geological quality of the soils, whichrisk liquefaction and that thus amplify a relativelylow seismic risk; on the other, the risk oflandslides from the steep slopes surroundingthe valley. Such risks are considered low onaccount of the current level of population andassets exposure, but are rated as medium forthe 2030 scenario.ds:X XXXX XXXX XXXXX XXXX XXXX XXXXX XXXX XXXX XXXXWater resources scarcity: Water supply issubject to few pressures today, but water scarcitywould be considered a medium risk by 2030,assuming current estimates of population andindustrial growth. The development of the BouregregValley could in itself contribute significantlyto pressures on limited water sources for coastalMorocco.The valley is hemmed in by steep slopes, which are subject tolandslides and rock slides. These would threaten buildings within theplanned development. Risks could increase with climate change andmore frequent torrential storms.Adaptation and Resilience ResponsesData on low lying areas can help planners avoidlocating populations and properties in parcels of landlikely to be inundated during episodes of torrentialBy 2030, marine submersionrisks related to an exceptional100-year storm would extendbeyond the presently vulnerableareas indicated in blue to includeadditional areas indicated in red.

NORTH AFRICAN COASTAL CITIES ADDRESS NATURAL DISASTERS AND CLIMATE CHANGE | 23rains or floods. For other areas, structures can be designedto withstand the expected stresses. Buildingscan be sited, adapted and reinforced in ways thatwould lessen the damage from natural disasters andextreme weather.Climate-smart PlanningThe assessments necessarily reflect the dynamicnature of the various risks. For example, downstreamfrom the Moulay Hassan bridge, there are significantflooding risks from weather events historicallyconsidered likely only once every century. Althoughprecise adjustments do not exit, there is a broadunderstanding that under most climate changescenarios, episodes of extreme weather will happenmore frequently, so that a 100-year event soonmay be likely to occur as often as once every fiftyyears. Planning new infrastructures and buildings inthe Bouregreg Valley should take into account suchchanges, as well as the expectation that the sealevel will rise by as much as 20 cm by 2030 andcontinue to rise.Development plans will have to take into accountwater flows, ground absorption and drainagechallenges in the areas most subject to flooding.Aspects of the current development planraise concerns. For example, plans for the KasbatAbu Raqraq area envision housing constructionon part of a flood plain, with as many as 50,000people potentially exposed to flood risks.Overall, an audit and review of zoning, buildingand infrastructure plans for the Bouregreg Valleycould lead to a series of project adjustments thatcould render the development far less vulnerable.Investing in climate-smart planning at thisstage, before structures are in place, would surelygenerate significant savings over time.

To learn more about the study, download the full reportsand view related materials on the following web-sites:www.cmimarseille.orgThe Marseille Center for Mediterranean Integration (CMI)aims to enhance the convergence of sustainable development policiesby providing a platform for knowledge sharing and joint learning.http://arabworld.worldbank.orgThe Arab World Initiative (AWI) is a World Bank Group partnershipwith the countries of the Arab world designed to fostereffective cooperation and collaboration in the interests ofeconomic integration and knowledge sharing.