M 6.4 Albania Earthquake Global Rapid Post Disaster Damage Estimation (Grade) Report

Home , 46th parallel north, Kotor, Kurbin, Mamurras, Shijak, Ulcinj

FUNDED BY THE______EUROPEAN UNION ______

DECEMBER 16, 2019

Source: http://theconversation.com/can-one-earthquake-cause-a-cascade-of-more-127946

M 6.4 ALBANIA EARTHQUAKE GLOBAL RAPID POST DISASTER DAMAGE ESTIMATION (GRADE) REPORT

WORLD BANK GPURL D-RAS TEAM

______

Disclaimer

This work is a product of the staff of The World Bank with external contributions. The findings, interpretations, and conclusions expressed in this work do not necessarily reflect the views of The World Bank, its Board of Executive Directors, or the governments they represent.

Further, the World Bank does not guarantee the accuracy of the data included in this work. The boundaries, colors, denominations, and other information shown on any map in this work do not imply any judgment on the part of The World Bank concerning the legal status of any territory or the endorsement or acceptance of such boundaries.

The sole responsibility of this publication lies with the author. The European Union is not responsible for any use that may be made of the information contained therein.

______

Acknowledgements

This report was prepared by a team led by Rashmin Gunasekera and Oscar A. Ishizawa (Urban, Disaster Risk Management, Resilience and Land Global Practice - GPURL, World Bank). The team also comprises of James Daniell, Antonios Pomonis, Joshua Macabuag, Andreas Schaefer, Maria Gaspari, Antonio Correia and Kerri Cox of the World Bank’s GPURL Disaster Resilience Analytics and Solutions (D- RAS) Knowledge Silo Breaker (KSB).

The team gratefully acknowledges the contribution and guidance of Daniel Kull, Alice Mortlock and Alanna Simpson of the Europe and Central Asia (ECA) GPURL Urban and Disaster Risk Management team and Manya Deyanova of Mott MacDonald.

The team is also grateful for the financial support from the European Union (EU) in the framework of the EU-WB/GFDRR Western Balkans DRM Program, managed by the Global Facility for Disaster Reduction and Recovery (GFDRR).

The team also gratefully acknowledges the contributions in data, guidance and information of Mott MacDonald; the Center for Disaster Management and Risk Reduction Technology (CEDIM) at Karlsruhe Institute of Technology (Ann-Kathrin Edrich, Susanna Mohr, Michael Kunz); and the COPERNICUS emergency mapping service.

Abbreviations

COPERNICUS EMS: COPERNICUS Emergency Mapping Service DaLA: Damage and Loss Assessment D-RAS: Disaster-Resilience Analytics & Solutions, GPURL, World Bank Group GRADE: Global RApid post-disaster Damage Estimation GPURL: Urban, Disaster Risk Management, Resilience and Land Global Practice HOTOSM: Humanitarian OpenStreetMap Team OSM: Open Street Map PDNA: Post-Disaster Needs Assessments TEV: Total Exposure Value US$: United States Dollars

______Datasets Used

Hazard Data: • Local reconnaissance data • COPERNICUS EMSR412 data • Social media sourced data on intensities • CATDAT (historical info) • USGS, EMSC, CATNews, EarthquakeReport data on intensities

Exposure Data: • Construction Statistics 1995-2018 • Census Data 2001, 2011 • Enterprise Census 2010, Business Register etc. • Investment Data • OSM and HOTOSM additions across Albania for all footprints and reanalysis • CATDAT • Agriculture (Census 2011 etc.) and National Accounts Data • Individual studies into various assets (INSTAT)

Vulnerability and Damage Data: • Building codes of Albania • Historical event data (DaLA, PDNA, CATDAT) • Empirical vulnerability functions • Social media and ground photo analysis and loss adjusting • Situation Reports • Daily Ground Briefs

______Contents Acknowledgements ...... 2 Abbreviations ...... 2 Datasets Used ...... 3 Executive Summary ...... 5 Summary of event characteristics ...... 7 1.0 Introduction: Event Description ...... 7 2.0 Analysis of Damage Distribution ...... 11 Building damage assessment summary ...... 11 Damage to non-residential buildings, educational facilities, hospitals/health centres, other public buildings ...... 14 Evolution of building practices and earthquake code design in Albania ...... 14 3.0 Post-Disaster Rapid Damage Estimation Methodology ...... 20 4.0 Results and Interpretation ...... 21 5.0 Discussion on Earthquake Risk and Conclusions ...... 26 6.0 References ...... 28 Annex A: Economic Damage Results by Municipality ...... 29

______Executive Summary

Following the magnitude 6.4 Durrës-Mamurras earthquake on November 26, 2019, a rapid post- disaster damage assessment, following the GRADE methodology1, was undertaken. The objective is to estimate the economic damages caused by the event 2 and understand the spatial distribution of damages to support the process of developing a roadmap for recovery and reconstruction. Damage to buildings and infrastructure that resulted primarily from strong ground motion was assessed using a combination of government damage data; hazard modelling of the earthquake ground motion footprint; development of a buildings and infrastructure exposure database via census and capital stock information; and the assignment of structural vulnerability functions to existing structural typologies in Albania. Economic damage estimation results for the four most affected municipalities in the epicentral zone, as well as groups of municipalities in Tirana, north and south of the epicentral zone, and in the rest of the country were determined.

Tables 1 and 2 show the estimated replacement costs and the relative impacts as a percentage of Total Exposure Value (TEV) for six sectors: residential (housing), infrastructure, education, health, commercial/public and industrial. The damage estimates cover buildings and contents. The analysis at this point does not evaluate the impact on loss in terms of economic flow (e.g. business interruption), it only assesses economic damage to capital stock.

Class “Commercial/Public” includes non-residential buildings (private or public) that are not in the education, health, industrial sector (e.g. retail, administration, hotels, etc.). “Infrastructure” includes roads, bridges, ports, airports, railways, embankments, culverts, etc. In “rest of Albania” included are another 18 affected municipalities further away from the areas that suffered the most serious effects. Please also refer to the modeled seismic intensity distribution map in Figure 3, where areas with intensity 5 (V) or below are expected to have suffered none or minimal effects.

1 Global RApid post-disaster Damage Estimation (GRADE) approach developed at the World Bank and conducted by the Global Practice for Social, Urban and Rural Development, and Resilience (GSURR) Disaster-Resilience Analytics & Solutions (D-RAS) Knowledge Silo Breaker (KSB). The methodology aims to address specific damage information needs in the first few weeks after a major disaster See https://www.gfdrr.org/sites/default/files/publication/DRAS_web_04172018.pdf for details of the methodology. 2 Using capital replacement costs which is the actual cost to replace an asset at its pre-damage condition. This may not be the "market value" of the asset, and is typically distinguished from the "actual cash value" payment which includes a deduction for depreciation etc. 5

______Table 1. Estimate of the breakdown of the economic damage in absolute values (in US$ millions). The yellow bar highlights the damage severity in each zone relative to the damages in the epicentral zone for each sector.

Affected Zones Commercial / (Municipalities) Residential Infrastructure Education Health Public Industrial TOTAL Epicentral Area (Durrës, 301.7 20 21.5 8.6 49.0 27.8 428.6 Krujë, Shijak, Vorë) Tirana and Kamëz 202.7 7.2 12.6 4.0 23.2 12.8 262.5 North of Durrës (Lezhë, 33.5 0.9 2.1 0.5 2.6 1.4 41.0 Kurbin, Mirditë) South of Durrës (Kavajë, 33.9 0.7 0.6 0.4 2.4 1.4 39.4 Peqin, Rrogozhinë) Rest of Albania 44.9 0.4 1.1 0.3 1.6 0.8 49.1 TOTAL 616.7 29.2 37.9 13.8 78.8 44.2 820.6

Table 2. Estimate of the breakdown of the relative economic damages as percentage of total exposure value for the sector.

Affected Zones Commercial / (Municipalities) Residential Infrastructure Education Health Public Industrial TOTAL Epicentral Area (Durrës, 13.3% 1.5% 15.6% 12.7% 11.2% 10.4% 9.5% Krujë, Shijak, Vorë) Tirana and Kamëz 3.9% 0.2% 3.8% 2.5% 2.3% 2.1% 2.5% North of Durrës (Lezhë, 4.1% 0.2% 3.1% 2.0% 1.8% 1.6% 2.5% Kurbin, Mirditë) South of Durrës (Kavajë, 4.5% 0.1% 1.6% 1.6% 1.6% 1.4% 2.6% Peqin, Rrogozhinë) Rest of Albania 0.4% 0.0% 0.1% 0.1% 0.1% 0.1% 0.2% TOTAL 3.2% 0.3% 2.9% 2.4% 2.2% 2.0% 2.1%

The results show that the economic impacts are dominated by damages to residential buildings (three quarters of the total), followed by commercial/public buildings (just under 10% of the total), while effects to the infrastructure and the health sector are the lowest. More than half of the total damages occur in the four municipalities (Durrës, Krujë, Shijak and Vorë) around the epicentre of the earthquake, and just under a third in the Tirana area (Tirana and Kamëz municipalities).

The estimated economic damage ratios in the four municipalities around the epicentre of the earthquake range from 1.5 percent for infrastructure to 15.6 percent for the educational building stock, while in the Tirana zone the economic damage ratios range from 0.2 percent for the infrastructure to 3.9 percent for the residential sector. The high impact on the residential building stock could affect the recovery of the affected region, especially in the epicentral zone, unless reconstruction is efficiently planned and financed.

______Summary of event characteristics

The November 26, 2019 Magnitude Mw 6.4, Durrës-Mamurras earthquake is a moderate sized event, typical of those experienced in some Southern European countries that cause damages to the building infrastructure primarily. These events are exacerbated when the impacted building stock contains many aging buildings often constructed prior to the introduction of modern seismic design principles. This was the case in Albania.

In Albania, an additional aggravating factor was that the earthquake occurred between the country’s two major urban agglomerations, the Tirana agglomeration with 705,500 people and the Durrës agglomeration with 201,500 people (2011 census). In Tirana, much of the building stock is aging and in poor state of maintenance; while in the port city of Durrës, the ground motion was amplified due to the weak, unconsolidated soils and coastal estuaries that are predominant in the area, seriously affecting many multi-story structures.

In the first three days following the earthquake, the focus was on saving as many people as possible trapped under collapsed buildings in Durrës and Thumanë; while after that, the focus switched to assessing the damage to buildings as it was necessary to reassure people about the safety status of the buildings in which they lived or worked. As a result of the damage, around 14,000 people are at least temporarily homeless, while around 10,000 people in the Durrës region are at least temporarily unemployed.

In both stages, international assistance was of great help to the overstretched Albanian authorities’ ability to respond, with foreign search and rescue teams at some point exceeding 100 personnel; while in the following days, more than 100 engineers from neighboring countries arrived to assist with the building damage-safety assessments.

1.0 Introduction: Event Description

On November 26, 2019 at 03:54 hrs local time, an earthquake of magnitude Mw 6.4, with focal depth of 20 km, struck northwest Albania around 60 minutes after a magnitude 4.4 foreshock had alerted the people of Durrës. This strong earthquake caused extensive damage to at least 10 of the country’s 61 municipalities (Figure 1), including the two most populous, urbanized and developed municipalities (Tirana and Durrës). The worst affected municipalities were: Shijak, Durrës, Krujë, Tirana, Kamëz, Kavajë, Kurbin and Lezhë. The total population of these municipalities accounts for 1,076,000 people (2011 census) or 38% of the total in the country.

The November 26 earthquake’s epicentre was north of the city of Durrës, although the macroseismic effects were most extensive in the Shijak municipality that is situated about 10 km east of Durrës. The earthquake caused 51 fatalities and at least 913 injuries (including 255 people injured during the aftershocks). The fatalities occurred primarily due to the collapse of 10

______buildings in the city of Durrës and in the town of Thumanë (in Krujë municipality). In Durrës, 23 people died due to the collapse of seven buildings, including three hotels and a convention Centre; while 24 died in Thumanë due to the collapse of three old (pre-1991) apartment blocks that had apparently been damaged by the September 21 earthquake. In addition, 45 people were pulled out alive from the ruins of these 10 buildings and later survived (22 were still in hospitals as of December 5). As a result, this was Albania’s most lethal earthquake since the 1979 magnitude Mw 6.9, April 15th earthquake that severely affected the coastal area of Montenegro from Kotor in the north to Ulcinj in the south. That earthquake left up to 100,000 people homeless.

The November 26 earthquake was also preceded on September 21 at 16:04 hrs local time by magnitude Mw 5.6 earthquake, with focal depth of 10 km, that occurred 5 km north of Durrës city injuring 108 people and causing damage to more than 2,000 buildings and 47 educational facilities, including considerable damage in the capital city of Tirana (city-proper population 418,500 in the Oct. 2011 census) and in the port city of Durrës (city-proper population 113,250 in the Oct. 2011 census). A magnitude 4.8 earthquake with focal depth at 10 km had also occurred on July 4, 2018 in the same region and had apparently caused some damage including to a school in Thumanë. These earthquakes are significant as it increased the vulnerability of buildings and of communities.

Figure 1: Map of Albania’s municipalities.

______

The location of these earthquakes is not a surprise as they were centered within the Balkan Peninsula’s highest seismic hazard zone (Figure 2). The November 26 earthquake was followed by four aftershocks of magnitude 5.1 to 5.4 in the 36 hours after the mainshock. These aftershocks caused additional damage or progressive collapse of badly damaged buildings with the M5.4 aftershock that occurred at 07:08 local time on November 26 being quite damaging in Durrës (Figure 3).

Figure 2: Clip from the SHARE European Seismic Hazard map, centred around Albania, displaying the ground shaking expected to be reached or exceeded with a 10% probability in 50 years, corresponding to an average recurrence interval of 475 years. The darkest shade corresponds to a horizontal ground motion acceleration of 0.4 to 0.8g (Giardini et al., 2013).

______

Figure 3: Map showing the modeled seismic intensity distribution of the main shock. The red darkest colour corresponds to intensity VIII (severe) on the European macroseismic intensity (EMS-98) scale and the yellow and orange shades correspond to intensities VI and VII (strong and very strong, respectively).

All of these earthquakes occurred in the convergent boundary between the Eurasian Plate and the Adriatic Plate, part of the complex collision zone with the African Plate, where tectonic compression of the Earth’s crust extending from Croatia in the north to Greece in the south is giving rise to high seismicity, with a long history of large earthquakes in the region. In this tectonic context, western Albania is host to several active thrust faults, some of which are exhibited on the ground surface while others are “blind” and instead fold the overlying strata. Such a fold exists in the region between Durrës and Tirana, running in a NNW-SSE direction and rising up to 200 m in altitude; this is where the November 26 earthquake most likely originated.

A number of historic earthquakes have occurred in the Durrës-Krujë area including the 1237, 1273, 1617, 1852, 1870, 1895, 1896 and 1926 events. The magnitude 6.1, December 17, 1926 earthquake occurred at 12:39 hrs local time, and caused damage and two deaths in Durrës and Kavajë, though thankfully a foreshock of magnitude 5.8 had taken place 5 hours earlier that had alerted the population. More recently, a Mw 5.0 earthquake occurred near Durrës on September 5, 2007 causing only slight effects. Other earthquakes of significance since 1900 in Albania include the June 1, 1905 in Shkodër; the November 26, 1920 in Tepelenë; the November 21, 1930 in Vlorë; the December 2, 1930 in Vlorë; the January 28, 1931 in Korcë; the May 26, 1960 Korcë; the March

______18, 1962 Fier; and the November 30, 1967 Librazhd earthquakes. These eight lethal earthquakes have caused in total 513 deaths in Albania as well as significant economic damages. 2.0 Analysis of Damage Distribution

Building damage assessment summary

Soon after the earthquake, the international engineers were coordinated via a Damage Assessment Coordination Cell (DACC) that was set up and operated jointly by the EU Civil Protection Mechanism Team (EUCPT), the UN Disaster Assessment and Coordination (UNDAC) team, and a team from the United States Agency for International Development (USAID). The role of the DACC was to support the Albanian government in coordinating joint assessments between international and national engineers. Joint teams of international and Albanian engineers conducted a ‘phase 1’ rapid visual building safety assessment, which focused on critical life-safety buildings, whilst also mentoring the Albanian engineers to continue the assessments of the less- damaged buildings after the international engineers returned home.

Collection of overall damage data remained the responsibility of the Albanian government, and so these official figures have been used in this report. Damage statistics in Tables 3 and 4 relate to single-family houses, apartment blocks that contain usually more than ten housing units, as well as non-residential buildings. According to the Office of Albania’s Natural Disaster Management Operations, on December 10 in the epicentral region, the rapid first-degree building damage assessment statistics were as shown in Table 3. It must be noted that these are not the final numbers; for example, in ward no. 5 of Durrës, out of 7,580 existing buildings, only 2,000 are reported to have been assessed so far. It is noted that Shijak municipality is worst affected, although large building demolitions have so far only taken place in Durrës city (34 demolished structures), Thumanë town (10 demolitions) and Bubq village (2 demolitions).

Table 3: Building damage statistics from the Office of Natural Disaster Management Operations in three municipalities in the epicentral region (as of Dec. 10, 2019).

Durres M. Kruja M. Shijak M. COMBINED Inspected 2112 2499 1670 6281 Safe 1368 1533 346 3247 Uninhabitable 651 921 900 2472 Demolition 93 45 424 562 Demolished 34 12 0 46

Safe 64.8% 61.3% 20.7% 51.7% Uninhabitable 30.8% 36.9% 53.9% 39.4% Demolition 4.4% 1.8% 25.4% 8.9% 11

______

Further away from the epicentral zone, damage was lighter, as exhibited in Table 4 for the three municipalities that are situated north of the epicentral zone (data as of December 10), although damage assessments there may not yet be as advanced-completed as in the epicentral zone. For example, in Durrës city, a 12-story apartment block containing 245 housing units had serious structural and non-structural damage.

Table 4: Building damage statistics from the Inter-Ministerial Committee for Emergency Situations in Lezhë in three municipalities situated north of the epicentral region (as of Dec. 12, 2019).

Kurbin M. Lezha M. Mirdita M. COMBINED Inspected 1000 1200 80 2280 Safe 754 1130 29 1913 Uninhabitable 239 70 51 360 Demolition 7 0 0 7

Safe 75.4% 94.2% 36.3% 83.9% Uninhabitable 23.9% 5.8% 63.8% 15.8% Demolition 0.7% 0.0% 0.0% 0.3%

In addition, by December 11 in Tirana municipality, it was reported that 254 buildings were classed as “red” (i.e. a decision about their demolition needs to be taken and, in the interim, the buildings must be evacuated) and 342 buildings were classed as “yellow” (i.e. the final determination of their damage state will be decided after a detailed second-degree damage assessment); while another 794 buildings were deemed safe to enter having suffered lighter damage (“green”). An analysis of the data containing 1030 buildings, as of December 7, is shown in Table 5.

As these datasets do not include the number of “undamaged” buildings, it is difficult to draw definite conclusions; however, it can be seen that among the assessed buildings, those that were built prior to 1992 suffered more damage than those built in or after 1992 (43.6% of the pre-1992 buildings were classed as red or yellow as opposed to 28.4% of the post-1991 buildings). Damage was most extensive among the low-rise buildings (1 or 2 floors) that were assessed (70.2% were classed as red or yellow), and least extensive among the high-rise (6 or more floors) buildings (22% were classed as red or yellow). This is partly because the low-rise buildings consist of many old unreinforced masonry houses made with adobe or clay brick or concrete block walls, while the tall buildings are almost exclusively of reinforced concrete construction and mostly built after 1991. The mid-rise buildings (3 to 5 floors), on the other hand, consist of a mixture of structural types (brick masonry, structural masonry, reinforced concrete) and were built across both examined periods of construction. In terms of type of structure, it is noted that prefabricated structures, followed by reinforced concrete and structural masonry structures have been mostly assessed as having light-moderate damage (“green”). It must also be noted that the numbers

______are not finalized and the number of green buildings is expected to rise, as more buildings with lighter damage are inspected now that the rapid phase 1 life-safety phase is complete.

Table 5: Analysis of building damage statistics in Tirana from the Tirana Municipality (by period of construction, number of floors, type of structure and 3-colour scheme damage levels).

Green Yellow Red Building Characteristics (Safe) (Review) (Evacuate) pre-1992 56.3% 23.6% 20.0% post-1991 71.6% 15.3% 13.1% Unclassified 47.0% 16.6% 36.5%

1-2 floors 29.8% 22.2% 48.0% 3-5 floors 60.6% 23.4% 16.1% 6+ floors 78.0% 14.0% 8.1% Unclassified 66.3% 12.5% 21.2%

Adobe walls 17.4% 17.4% 65.2% Brick Masonry 56.1% 20.9% 23.0% Concrete Block Masonry 9.1% 9.1% 81.8% Prefabricated 86.2% 10.3% 3.4% Reinforced Concrete 71.7% 16.0% 12.3% Structural Masonry 62.8% 21.8% 15.4% Unclassified 4.0% 36.0% 60.0% TOTAL 60.6% 19.2% 20.2%

Furthermore, in Tirana three buildings were demolished in Student City while another 10 are awaiting demolition in the Agriculture Institute campus (all of these are pre-1992 structures). In Laç town (capital of Kurbin municipality) seven buildings have also been issued with demolition orders.

As of December 12, damage in other affected municipalities has not yet been reported in detail. On December 11, Government sources said that 14,069 buildings have been assessed so far across the country, of which 261 apartment blocks and 2,237 houses had severe damage; while 851 apartment blocks and 4,618 houses had light or medium damage. It is considered that these are not the final numbers. From a tally of the Ministry of Interior announcements, it is considered possible that around 25,000 buildings including single-family houses, apartment blocks and non- residential buildings may have been damaged to various degrees across the country, as damage surveys in the rural areas have not yet progressed sufficiently. Albania’s building stock is estimated to contain in total more than 800,000 residential and non-residential buildings.

______Damage to non-residential buildings, educational facilities, hospitals/health centres, other public buildings

Assessment of damage to schools and health facilities has been given priority, with 36 schools reported as severely damaged (some will be demolished), 6 with moderate damage, and 176 with light damage. In the health sector, there were 12 damaged facilities, primarily health centres— although the hospital in Laç and the health centre in Mamurras had to be evacuated—while significant damage also occurred in the "Koco Gliozheni" maternity hospital and the Cardiology service at Trauma Hospital in Tirana.

Damage to other public buildings has also been reported, such as a building in the Convention Centre complex of the Ministry of Interior in Durrës that collapsed, causing the death of one person; a mosque in Thumanë; the municipal building and the Prosecution-Court buildings in Laç; the Prosecutor's Office, the Presidency of the Assembly buildings and the Regional Tax Directorate in Tirana; the Court of Appeal and Prosecutor's Office building in Durrës; the Kurbin Police Station building; 10 buildings in the Kamzë Institute; and the Lezhë Court building, among others. In addition, damage to the cultural heritage sites of Prezë Castle and Krujë Fortress Tower has also been reported.

The effects on the tourism sector are also significant, especially in the Durrës coastal zone where the hotels Mira Mare, Tropikal and Villa Palma collapsed, killing five occupants; while hotels Lubjana, Villa Verde and Gostivari had to be demolished. All of these hotels were situated in the city’s coastal zone. It was thus quite opportune that the earthquake occurred during the winter season when these large hotels had low occupancy.

Effects on the industrial sector have also been significant, with an aluminium factory collapsing in Shkozet and a recycling plant being seriously affected in the Porto Romano area. In total, 130 industrial facilities have been damaged in the Durrës area, as an industrial park is situated between Durrës and Shijak where earthquake shaking was most severe. It is likely that this tally is not the final one for the industrial sector.

Evolution of building practices and earthquake code design in Albania

Albania is a country characterized by high seismic activity and its earthquake catalogue contains events that have taken place over a period of nearly 2000 years, starting from an earthquake in the Durrës region that occurred in 57 AD. Seismicity is mainly concentrated in the west, in the Ionian-Adriatic Sea seismic belt, where the September 21 and November 26, 2019 earthquakes took place; while further inland, there are seismic activity zones along the Vlore-Elbasan-Dibër and the Korcë-Ohrid-Peshkopi seismogenic zones. Albanian earth scientists have compiled the seismic zonation of the country first in 1952, with updates in 1963 and 1980.

______Major building structures are designed according to the Albania Earthquake Resistant Regulations (seismic design codes) introduced first in 1963 and then updated in 1978 (KTP-1978) and in 1989 (KTP-N.2-89). The seismic zonation map of Albania in the KTP-1978 code is shown in Figure 4 (left), while the zonation in the current seismic code is shown in Figure 4 (right) and is based on work of the Seismological Center, Academy of Sciences of Albania published in Sulstarova et al. (1980).

The seismic zonation of Dürres and surrounding areas has not changed significantly between the 1963 and the KTP-1978, KTP-N.2-89 codes, with both attributing it with VIII intensity. On the other hand, Tirana was originally classified as VI intensity (1978 code); with an update to VII in the 1989 code.

Figure 4. Left: the zonation with mostly intensity VI and VII used in KTP-1978, which for Tirana gives elastic spectra in the order of 2-3 times lower than the 1989 code; Right: the intensity zonation used in KTP-N.2-89 from Sulstarova (1978, 1980), with intensities mostly VII and VIII (Hima, 2016; KTP-N.2-89)

The 1989 code’s zonation map represents the expected seismic intensities for average soil conditions for the next 100 years with probability of exceedance of 70 percent. The map outlines three zones of macroseismic intensity VIII, VII and VI degrees in the MSK intensity scale (which

______corresponds broadly to the Modified Mercalli and the 1998 European Macroseismic intensity scales).

The 2019 earthquakes occurred within the intensity zone VIII. According to this work, in locations with poor soil conditions, seismic intensity may attain IX degrees. Following this work and during the 1980’s, seismic micro-zonation mapping of major urban centres in Albania was carried-out including Tirana and Durrës. The map in Figure 5 shows the liquefaction potential map of Durrës (Kociu, 2004). Field surveys in Durrës have highlighted that, although not extensive, liquefaction did occur on November 26 near the site of some of the collapsed buildings, such as the Mira Mare hotel which is situated on the coast on top of sandy soil (Lekkas et al., 2019). Liquefaction is a phenomenon in which the strength and stiffness of a soil is reduced due to earthquake shaking. Buildings on top of liquefied soils can sink, tilt, get badly damaged or even collapse.

Figure 5: Liquefaction potential map of Durrës city (Kociu, 2004). Zone 1: Areas highly susceptible to liquefaction, Zone 2: Areas moderately susceptible to liquefaction and Zone 3: Areas where the liquefaction is less susceptible

Building stock in Albania can broadly be divided into the period before 1991 and afterwards, in line with the transition of the Albanian economy from a state-controlled system up to 1991, to a free market-based economy afterwards. Albania’s GDP peaked at 2.25 billion US$ in 1989, followed by a deep recession during the transition period (1991-97). The country’s GDP reached again the 2.25 billion US$ level in 1997. Since 1998, a period of rapid growth meant that the country’s GDP was by 2019 around seven times greater than in 1997. Much of this growth was led by activity and investments in the construction sector, including investments in buildings, with a boom in construction and land occupancy since the late 1990s.

______

Albania’s building stock currently comprises of more than 800,000 individual structures. The predominant structural types in the planned economy period (up to 1991) comprise mostly of: • Unreinforced load-bearing masonry structures (adobe, stone or solid clay brick masonry of 1-2 floors and solid brick or concrete block masonry of 3 to 5 floors), • Structural masonry with reinforced concrete column elements and slabs (commonly from 3 to 6 floors), • Precast reinforced concrete wall panels with precast reinforced concrete slabs (4 to 6 story structures), and • prefabricated reinforced concrete structures (in the industrial sector).

It should be noted that these buildings usually did not exceed 6 floors (around 20 meters in height); and currently the state of maintenance of many pre-1992 buildings is rather poor.

After the transition period to a market economy and especially after 1997, buildings with reinforced-concrete (RC) framing system and infill baked clay and/or concrete block walls (from 2 to more than 10 storied structures) became common practice, while the practice of building in unreinforced or structural masonry or precast panels was gradually ceased, with the exception of small houses in rural areas. The quality and adherence to the codes of these new buildings varies, with higher adherence taking place in the urban areas. In addition, the practice of incremental construction is quite widespread with buildings issued with permits for a certain number of floors ending up having additional floors in ensuing years. Some of the collapsed buildings in Durrës belong in this category, such as the Mira Mare hotel, the Tropikal hotel, the Villa Palma hotel and the four-story villa in Kennete (a village just north of Durrës).

The Eurocode suite of standards has been gradually translated and accepted as Albanian standards since 2012, but insufficient coordination between different national authorities has been pointed out. Also, lack of technical expertise and financial and legislative support to develop and approve the National Annexes and Nationally Determined Parameters has been referred, such as the ground classification and seismic zonation.

The Tirana 2-component horizontal spectral acceleration in Figure 6 of the present earthquake, with up to 0.35g, appears to exceed the KTP-N.2-89 spectra for Tirana (stiff soil, beta=2), and to far exceed the zonation in KTP-1978. Considering this, most buildings responded well but it would be suggested that the effects of this event be included in any future seismic zonation (and micro- zonation) work. Unfortunately, there was no strong motion recorded in Durrës, as in recent years (after 2007) the strong motion observation network of Albania has been diminished.

______

Figure 6: Elastic Spectra (Horizontal) vs. the K(TP-N.)2-89 code elastic spectra for Tirana on stiff soil.

The residential and non-residential building stock exposure was developed using capital stock data merged with ground-up unit cost of construction data. For the residential stock data, the 2001 and 2011 Albania Population and Housing Census were used to project to 2019 and to understand the distribution of the country’s housing units across different construction typologies, heights and periods of construction. This is highlighted in Figure 7.

______

Figure 7: Residential exposure map of the main earthquake affected zone in 2019 at municipality level. Pie-charts are sized according to the size of the exposure and show the distribution of the exposure (in 2019 million US$ values) according to broad vulnerability classes, taking into account structural type, period of construction and number of floors. SB= stone or brick masonry, RC=reinforced concrete.

______3.0 Post-Disaster Rapid Damage Estimation Methodology

To derive the economic loss estimates for the event, the World Bank GPURL D-RAS KSB team adapted the GRADE approach.

For this event, hazard footprint datasets were developed and referred to shaking intensity maps that were produced based on remote sensing damage assessment4. These estimates were checked against ground truthing of the shaking and modified where needed. It was found that, due to the nature and uncertainty of the fault rupture, a pure Shakemap-style methodology could not be used, and thus felt reports, spectra (TIR) and damage observations were used to modify the map beyond standard internet-based reports. Modified intensity maps were produced based on spectra-based intensity. Both ground-based and satellite images and social media feeds were used to derive a composite damage distribution analysis. The team also looked at replacement cost as opposed to reconstruction cost.

To derive the economic exposure values, the team used highly disaggregated macro-economic (capital stock) information to corroborate detailed estimates. Data (including county data) on capital investment was used in order to provide capital stock checks for building and non-building proportions.

The team used building footprint datasets to derive the existing built floor area. Unit costs of construction appropriate for the area were also derived from local information, but also use was made of media feeds on the costs of existing housing projects in the area, construction statistics, as well as on the costs proposed after the earthquake. Unit costs of construction for the replacement of destroyed, or the repair of damaged buildings (depending on the damage level), were thus obtained.

For the education sector, detailed level data was used from education ministry data on schools available (both public and private) to determine geospatial exposure distribution and damage ratio calculations.

The team also assessed against and rectified damage distributions produced by local and international agencies (COPERNICUS) to also account for already derelict buildings before the earthquake and potential miscalculation of damage.

Several cross-validation tasks were performed to enhance corroboration of economic damage estimation. The team also used experience and estimates from the Albania earthquake for comparison purposes.

______4.0 Results and Interpretation

Economic damage estimation results for the four most affected municipalities in the epicentral zone, as well as groups of municipalities in Tirana, north and south of the epicentral zone and in the rest of the country were determined. Tables 1 and 2 show the estimated economic damages and the relative impacts as percentage of Total Exposure Value (TEV) for six sectors: residential (housing), infrastructure, education, health, commercial/public and industrial. The damage estimates cover buildings and contents. The analysis at this point does not evaluate the impact on loss in terms of economic flow (e.g. business interruption); it only assesses economic damage to capital stock. Traditional earthquake loss estimation models fail to quantify the significant losses seen in certain sectors. Therefore, ground reports and post-disaster imagery were combined with risk modelling via the GRADE methodology. The total economic damage estimate is $820 million, $633 million of which is in structural and non-structural damage and approximately $187 million in contents.

Table 1. Estimate of the breakdown of the economic damage including building contents in absolute values (in US$ millions). The yellow bar highlights the relative distribution for each sector.

Table 2. Estimate of the breakdown of the relative economic damages as percentage of total exposure value for the sector.

______The results show that the economic impacts are dominated by damages to residential buildings, followed by commercial/public and industrial buildings, while effects to the infrastructure are much lower. More than half of the damages occurred in the four municipalities (Durrës, Krujë, Shijak and Vorë) around the epicentre of the earthquake, and nearly a third in the Tirana area (Tirana and Kamëz municipalities).

The estimated economic damage ratios in the four municipalities nearer the epicentre range from 1.5 percent for the infrastructure to 15.6 percent for the educational building stock. The high impact on the residential building stock could affect the recovery of the affected region unless reconstruction is efficiently planned and financed. The impact to the education sector was also significant, with at least 30 schools failing to re-open on December 9 due to serious damages and some University faculties in Tirana scheduled to resume education activity on January 6, 2020.

To put the damages further into perspective, the building exposure in Albania totals around US$26.8 billion. This value increases to over US$35 billion when including the estimated value of contents. The building exposure value represents around 190% of Albania’s GDP in 2018. Of this total building stock, around US$19.1 billion is in residential buildings exposure (this increases to US$24.4 billion when including the estimated value of residential contents). Figure 8 shows the building exposure per municipality in Albania. Of the $26.8 billion US$ in building exposure, $19.1 billion is in residential; $1.3 billion in education facilities; $0.6 billion in health facilities; $3.6 billion in commercial and other public buildings; and $2.2 billion in industrial facilities. The exposure value for all kinds of infrastructure (roads, bridges, railways, etc.) amounts to about half of the buildings’ exposure at $13 billion. Tirana and Durrës municipalities account for nearly one third of exposure values in Albania.

Figures 9 and 10 show the spatial distribution of the estimated economic damages across Albania’s municipalities for the entire capital stock and for the residential sector, respectively.

______

Figure 8: Total residential and non-residential buildings exposure per municipality.

______

Figure 9: Estimated economic damages for all capital stock in million US$ per municipality.

______

Figure 10: Estimated economic damages in the residential sector in million US$ per municipality.

______5.0 Discussion on Earthquake Risk and Conclusions

The report highlights the results of the economic damage estimation and spatial damage distribution after the November 26, Mw 6.4, Durrës-Mamurras earthquake in Albania. The event damage estimation was complex due to the uncertainties in the earthquake’s Shakemap, the wide variety of building typologies with starkly different vulnerability potential across the affected region, as well due to potential ground motion amplification in Durrës.

Most severely impacted were the residential buildings, followed closely by buildings in the education, health and commercial/public sectors. The results clearly show that the impact is severe to the epicentral area’s buildings, with damage ratios of 10.4 to 15.6 percent. Such damage ratios are rather high for a moderate magnitude event and are cause for concern as to the country’s overall seismic risk. Consequences in Tirana are also sizeable (exceeding $260 million) due to the large exposure concentration within the capital city and the relative proximity of this earthquake to the capital (epicentre around 25 km west of the Tirana city centre). Impacts outside the two main conurbations are locally severe (e.g. in Shijak and Krujë municipalities) but do not contribute significantly to the total costs, as these areas are rather less densely inhabited. Only about 15 percent of the earthquake’s economic damages occur in the areas outside the epicentral zone and Tirana.

The total economic damage estimate, including contents of the event, is ca. US$820 million3. Of the damages, approximately US$633 million is expected to be in the residential sector, and US$187 million in the non-residential building and infrastructure sector.

The added value of this analysis and report include: • The speed of analysis, the reduction of uncertainty using several sources of information (including social media), and the flexibility of the GRADE methodology to be applied to a series of events that incorporates the multi hazard components. • Checks of baseline data have also been conducted vs. high level estimates using sub- national level statistical reports, to ensure higher confidence in costs and asset values. • Collaboration has been undertaken between various groups using data from social media, COPERNICUS and ground surveys.

Regarding the building codes, large construction development has taken place since the late 1990s. However, despite the efforts in implementing the revision of building codes in Albania foreseen in the 2008 Disaster Risk Mitigation and Adaptation Project from The World Bank, there have been difficulties in the adoption and evolution to the suite of Eurocodes. These have been gradually translated and accepted as Albanian standards since 2012, but more support is needed in both the technical and legislative fronts for the development of the National Annexes. These

3 median estimate 26

______include the seismic zonation and intensity maps that should replace the ones of the 1989 code (KTN-N.2-89), still in force.

The country’s pre-1991 building stock is often in unsatisfactory state of maintenance attributed to many different reasons such as poor detailing, poor fittings and also the increasing need for more modern living conditions. Currently, around 63 percent of the rural housing units in Albania date from before 1992, while this ratio is at around 29 percent in the country’s urban areas (nearly 45 percent overall). The earthquake vulnerability of these buildings is rather high and will continue to influence overall earthquake risk in the country. Additional issues exist with the country’s vacant housing stock, which currently stands close to one third of the entire stock. These housing units are not sufficiently investigated by the consecutive-decadal housing census and need to be more carefully examined.

There are potentially serious earthquake vulnerability concerns related to multi-family apartment blocks prior and post 1991, where around a third of the country’s population live. The older apartment blocks suffer from poor earthquake design conception, including problems related to the floors often composed of simply supported precast reinforced concrete hollow core slabs that are not transversally connected to each other, neither to the load bearing system, or insufficient transverse reinforcement in the load-bearing elements. In addition, precast panel construction suffers from poor sealing of the panel joints which results in increased exposure to climate conditions that in the long-term will cause overall structural safety concerns. The newer apartment blocks, on the other hand, often exhibit significant earthquake vulnerability attributes such as the use of soft-stories, insufficient dimensions of columns, irregularities in structural layout horizontally and vertically, addition of floors without building permits, insufficient transversal reinforcement, and siting on poor soil conditions (especially in Durrës).

This report observes that there are potentially significant challenges to Albania’s structural engineering and architectural community. These challenges include: a) continuing the earthquake mitigation action plans, as well as efforts to further proceed with modernizing the seismic and environmental performance of the country’s existing building stock; and b) ensuring that new buildings have better seismic design provisions for seismic resilience.

______6.0 References

Giardini, D., J. Woessner, L. Danciu (2014) Mapping Europe’s Seismic Hazard. EOS, 95(29): 261- 262

Hima, N. (2016) “Studim mbi demtueshmerine e strukturave me skelet prej betoni te armuar“, Masters Thesis, UPI Tiranes.

Kociu S. (2004). Induced Seismic Impacts Observed in Coastal Area of Albania: Case Studies. 5th International Conference on Case Histories in Geotechnical Engineering,

KTP-N.2-89 “Technical Aseismic Regulations”. Publication of Academy of Sciences and Ministry of Constructions, Tirana (in Albanian), 1989.

Lekkas, E., Mavroulis, S., Papa, D., Carydis, P. (2019). The November 26, 2019 Mw 6.4 Durrës (Albania) earthquake. Newsletter of Environmental, Disaster and Crises Management Strategies, 15, ISSN 2653-9454.

Shebalin NV, Karnik V, Hadzievski D. (1974) “Balkan Region - Catalogue of Earthquakes.” UNESCO Office, Skopje, 1974.

Sulstarova E, Kociaj S, Aliaj Sh. (1980) “Seismic Regionalization of PSR of Albania.” Publishing House of “8 Nentori” Tirana, 1980; 1-297.

Sulstarova E, Kociaj S, Muco B, Peci V. (2003) “The Albanian earthquakes catalogue for historical and instrumental data with magnitude Mš4.5.” Internal Report (behalf on NATO Project “Seismotectonic and Seismic Hazard Assessment in Albania”, 1999-2002), Seismological Institute, Tirana, Albania.

Woessner, J., L. Danciu, D. Giardini and the SHARE consortium (2015), The 2013 European Seismic Hazard Model: key components and results, Bull. Earthq. Eng., doi:10.1007/s10518-015-9795-1.

______Annex A: Economic Damage Results by Municipality

The following are the municipality results of the GRADE process detailing median estimated damages for the key sectors in million US$. There is significant inherent uncertainty around any municipality level result as part of the earthquake loss estimation process due to differences in capital stock estimates, local differences unaccounted for in the seismic intensity assignments and soil conditions, possible secondary effects as well as structural vulnerability assignments. Therefore, we advocate to use caution in using these results.

Economic damage in USD millions rounded to nearest 0.1 decimal for key sectors by municipality. Affected Res. Infrastr. Education Health Comm./ Industrial TOTAL Municipalities Public Durres 226.7 16.3 16.5 6.9 39.8 22.7 328.9 Tirane 156.2 5.3 8.7 3.0 17.5 9.7 200.5 Kamez 46.5 1.9 3.5 1.0 5.7 3.1 61.7 Shijak 38.0 2.6 2.8 1.1 6.1 3.5 53.9 Kavaje 28.1 0.6 0.4 0.3 2.2 1.2 32.8 Kruje 26.2 0.8 1.7 0.4 2.3 1.2 32.7 Kurbin 16.7 0.6 1.3 0.3 1.6 0.8 21.3 Lezhe 15.1 0.3 0.7 0.2 1.0 0.5 17.8 Vore 10.8 0.3 0.6 0.2 0.8 0.4 13.1 Fier 7.0 0.1 0.2 0.0 0.3 0.1 7.7 Lushnje 6.1 0.1 0.2 0.0 0.2 0.1 6.7 Elbasan 5.5 0.0 0.2 0.0 0.2 0.1 6.0 Vlore 5.0 0.0 0.1 0.0 0.2 0.1 5.5 Divjake 4.9 0.1 0.2 0.0 0.2 0.1 5.5 Rrogozhine 3.6 0.0 0.1 0.0 0.1 0.1 4.0 Shkoder 2.8 0.0 0.1 0.0 0.1 0.1 3.0 Peqin 2.2 0.0 0.1 0.0 0.1 0.0 2.4 Berat 1.7 0.0 0.0 0.0 0.1 0.0 1.9 Mirdite 1.7 0.0 0.0 0.0 0.1 0.0 1.8 Kucove 1.6 0.0 0.0 0.0 0.0 0.0 1.8 Mat 1.6 0.0 0.0 0.0 0.0 0.0 1.7 Vau i Dejes 1.5 0.0 0.0 0.0 0.0 0.0 1.6 Cerriik 1.5 0.0 0.0 0.0 0.0 0.0 1.6 Belsh 1.4 0.0 0.0 0.0 0.0 0.0 1.5 Ura Vajgurore 1.2 0.0 0.0 0.0 0.0 0.0 1.3 Roskovec 1.2 0.0 0.0 0.0 0.0 0.0 1.3 Klos 0.8 0.0 0.0 0.0 0.0 0.0 0.8 Patos 0.5 0.0 0.0 0.0 0.0 0.0 0.5 Selenice 0.2 0.0 0.0 0.0 0.0 0.0 0.2 Bulqize 0.1 0.0 0.0 0.0 0.0 0.0 0.1

______