Earthquake Scenario and Recent Efforts Toward Earthquake Risk ...

Earthquake Scenario and Recent Efforts Toward Earthquake Risk Reduction in Nepal Deepak Chamlagain

Abstract Owing to its active tectonic movement the entire Himalayan belt is seismically active posing high risk of earthquake to millions of people living in the region. In the last century, Himalaya witnessed four major earthquakes that caused enormous environmental costs in the form of loss of life and property and the cost of rehabilitation. Geological and geophysical studies have identified the Main Himalayan Thrust, a plate boundary fault in between the Indian and Eurasian plates, as a major seismogenic fault in the Himalaya to generate most of the earthquakes in the region. Since Nepal is located at central part of the Himalaya, the mechanism and causes of earthquake are similar to that of other adjacent country. Occurrence of few damaging earthquakes during the last decade in Nepal and adjacent areas has pointed to our shortcoming in risk reduction programs. A meaningful program must incorporate, research, apposite building codes, and also effective public awareness plan. Several initiatives are now being taken at research and management levels in Nepal. In this contribution, both technical (e.g., seismicity, seismotectonics, neotectonics) and risk management practices (e.g., legislation, national plan, awareness programme) and their shortcomings are discussed. Keywords: Nepal Himalaya, Seismicity, Earthquake risk reduction.

Introduction The territory of Nepal spans about one third (i.e.~800 km) of the length of the Himalaya. It is located at the very central part of the active Himalayan belt. Because of its location in the active tectonic zone, climate, topography, fragile geological structures and intense rainfall, Nepal is vulnerable to various types of natural disasters like earthquakes, landslides, floods, mass movements, and GLOFs. Among

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DEEPAK CHAMLAGAIN all the natural disasters, earthquakes are the most disastrous since their impacts can cover large areas causing deaths, injuries and destruction on a massive scale. In case of great earthquake, the destruction is pervasive even it can stand still country for days to months. Over the last century, the Himalayan arc has been struck by four earthquakes (Fig 1) with magnitude ca. 8.5 in 1897 (Shilong earthquake) 1905 (Kangra earthquake) 1934 (Bihar-Nepal earthquake) 1950 (Assam earthquake) (e.g., Seeber and Armbuster, 1981) causing deaths of thousands of people (Table. 1). The 1905 Kangra earthquake produced severe damage in the Kangra area and, about 100 km to the east, in the Dehra Dun area. The estimated ruptured is about 280 km long segment, from Kangra to Dehra Dun, that must have extended eastward to about 78°E, near the border with Nepal (Chander, 1988; Yeats and Lillie, 1991; Gahalaut and Chander, 1997). Figure 1: Distribution of probable rupture zones of the 1897, 1905, 1934 and 1950 earthquakes along the Himalayan arc. Modified from Yeats and Lillie (1991) and Yeats et al. (1992).

The 1934 Bihar-Nepal earthquake was believed to rupture a 200-300 km long segment to the east of Kathmandu (Pandey and Molnar, 1988) (Fig 1).

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EARTHQUAKE SCENARIO AND RECENT EFFORTS TOWARD EARTHQUAKE RISK REDUCTION IN NEPAL Table. 1. Major damaging earthquakes in Himalaya and their casualties. Place

Date

Magnitude

Casualty About 1542 people died.

Shillong Plateau

Jun 12, 1897

8.7

Bihar-Nepal border

January 1, 1934

8.4

>10,653

Quetta, Pakistan

May 30, 1935

7.6

About 30,000

Assam, India

August 15, 1950

8.6

1500

Udayapur, Nepal

1988

6.5

1000 Approx.

Uttar Kashi, India

October 20, 1991

6.6

>2,000

Chamoli, India

March 29, 1999

6.8

>150

Hindukush, India

November 11, 1999

6.2

no death reported

Kashmir, Pakistan

October 8, 2005

7.6

74,698

In 2005, western Himalaya was hit by an earthquake with magnitude 7.4 killing more than 74,000 people from Pakistan and India. The location of ruptured areas shows a gap along the mountain range between the location of the Kangra (1905) and BiharNepal earthquakes (1934). It is believed that this region has not been experienced such an earthquake since the last large earthquake. This portion of the arc thus stands as a "seismic gap" (Fig 1), a potential location for the next large earthquake, unless the seismotectonic behavior of that area is very different from that of the rest of the Himalayan arc. This earthquake scenario evidently indicates that the entire Himalayan belt is one of the most vulnerable zones in terms of seismic hazard. Recent works on fault modeling (Chamlagain and Hayashi, 2004 and 2007) of Nepal Himalaya has shown continuous accumulation of elastic strain to reactivate older geological faults to generate earthquake of different magnitude. Moreover, several other lines of evidence (e.g. neotectonic, geomorphological, geophysical, geological, and seismological) also show that one or more mega-earthquakes may be overdue in a large fraction of the Himalaya (probably area between Kathmandu and Dehradun), threatening millions of people in the region. Recently, Wyss (2005) have calculated expected deaths and injuries for this region. He expected minimum fatalities of about 15,000 for an event located in sparsely populated western Nepal, to a maximum of approximately 150,000 deaths for an event located near the Dehra Dun segment, assuming the standard magnitude of 8.1. The number of injured is expected to range from 40,000 to 250,000, approximately. On this threatening surrounding of mega earthquakes, now it is necessary to refine our knowledge on seismotectonics, and earthquake risk of the region. Further, our efforts on risk reduction and earthquake disaster management that are being adopted should be reviewed and reassessed for the

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DEEPAK CHAMLAGAIN formulation of future strategies. In this paper, therefore, first seismicity and earthquake mechanism in Nepal is reviewed briefly; ongoing efforts to minimize the earthquake risk including legislation and national plan are then discussed.

Geo-Tectonic Framework of Nepal Himalaya The major tectonic features of Nepal Himalaya to the south of South Tibetan Detachment System (STDS) is controlled mainly by three major thrusts, e.g. from north to south the Main Central Thrust (MCT) Main Boundary Thrust (MBT) and Main Frontal Thrust (MFT) (Fig 2). These thrust faults with a N-S propagation direction are running almost the entire length of Himalaya and are generally inferred to be splay thrusts of the Main Himalayan Thrust (MHT), which marks the underthrusting of the Indian Plate. Figure 2: Geological map of Nepal (modified after Upreti and Le Fort, 1999). LH, Lesser Himalaya; HH, Higher Himalaya; TTS, Tibetan-Tethys sequence; MBT, Main Boundary Thrust; MCT, Main Central Thrust; MFT, Main Frontal Thrust; STDS, South Tibetan Detachment System.


EARTHQUAKE SCENARIO AND RECENT EFFORTS TOWARD EARTHQUAKE RISK REDUCTION IN NEPAL The MFT system consists of two or three thrust sheets composed entirely of Siwalik rocks, from bottom to top mudstone, multi-storied sandstone and conglomerate. These sedimentary foreland basin deposits form an archive of the final stage of the Himalayan upheaval and record the most recent tectonic events in the entire history of Himalayan evolution since ~ 14 Ma. The northernmost thrust sheet of the MFT is truncated by the Lesser Himalayan sequence and overlain by unmetamorphosed to weakly metamorphosed rocks of the Lesser Himalaya, where the Lesser Himalayan rock package is thrust over the Siwalik Group along MBT. In western Nepal, crystalline thrust sheets are frequently observed within the Lesser Himalaya, e.g. Dadeldhura crystalline thrust sheet (Hayashi et al., 1984). The Lesser Himalayan zone generally forms a duplex above the mid crustal ramp (Schelling and Arita, 1991; Srivastava and Mitra, 1994; Decelles et al., 2001). The MCT system overlies the Lesser Himalayan MBT system and was formed in ca. 24 Ma. This MCT system consists of high-grade rocks, e.g. kyanite-sillimanite gneiss, schist and quartzite and is mostly characterized by ductile deformation.

Active Fault in the Nepal Himalaya: A Potential Source of Earthquake The Himalaya is one of the most active mountain belts in the world. The active faults, in and around this belt are direct indicators of recent crustal movement due to the collision between the Indian and Eurasian plates. In this section, therefore, active faults and their seismic significances are reviewed, in order to clarify the earthquake source in Nepal. Active faults, in the Nepal Himalaya, (Fig 3), are distributed mainly along the major tectonic elements as well as older geological faults and are classified into four groups (Nakata, 1982); the Main Central Active Fault system, the active fault in Lower Himalayas, the Main Boundary Active Fault system and active faults along the Himalayan Front Fault (equivalent to MFT). Among these, active faults along the MBT and MFT are most active and have potential to produce large earthquakes in the future (Lave and Avouac, 2000; Chamlagain et al., 2000). The Himalayan front in the eastern Nepal is characterized by tectonic landforms produced by active faulting along both the MBT and MFT. In eastern Nepal, active faults trending NW-SE along the MBT merge with the active faults striking E-W along the MFT and extending farther south into the Gangetic plain (Fig 3). These active faults exhibit downthrows to the north. In central Nepal, traces of the active faults are continuous, especially in Hetaunda and south of the Kathmandu valley around the Bagmati River (Chamlagain et al., 2000; Kumahara et al., 2001). Active faults along the MFT also show northward downthrow. Active faulting along the MBT is represented by Arung Khola Fault, the Hetaunda Fault and Udaipur Fault in the east. The traces of these faults are

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DEEPAK CHAMLAGAIN continuous and north-facing scarplets suggest northward dipping fault planes. In western Nepal active faults along the MBT appear as a single continuous fault trace with rather straight linearity at many places. A common tectonic feature is a pressure ridge and the apparent vertical slip along the fault is down to the north. Active faults along MBT, though considered to be basically reverse faults, do not always have a displacement of the same nature in this area (Nakata et al., 1984) that is active faults close to the MBT are of normal type (Mugnier et al., 1994). Along the MFT, active fault appears as continuous in western Nepal. The characteristics of active faults along Himalayan front vary from place to place in the Nepal Himalaya and are attributed to the difference in volume of the Siwaliks resulting from the subsurface conditions of the collision. The stress trajectories derived from both observation (Nakata et al., 1990) and modeling (Chamlagain and Hayashi, 2008) show a disturbed pattern near the margin of the Eurasian Plate and are almost consistent with the direction of relative motion of the Indian and Eurasian plates. On the other hand, geomorphic analysis shows that MFT is the structure limited to south of the Himalaya which has absorbed on average 21 1.5 mm/yr of N-S shortening during Holocene period (Lave and Avouac, 2000). Figure 3. Active faults in and around Nepal Himalaya. Thick lines without tick marks show newly found active faults. Arrow indicates the direction of strike-slip. Downthrown side is shown by tick marks. Modified from Nakata and Kumahara (2002).


EARTHQUAKE SCENARIO AND RECENT EFFORTS TOWARD EARTHQUAKE RISK REDUCTION IN NEPAL

Earthquake Scenario in Nepal Himalaya Identifying time and location of local earthquakes is absolutely fundamental to planning ways of lessening the earthquake disasters in future. However, owing to the short instrumental record of the seismic events, the distribution of seismicity throughout the Himalaya appears nonuniform although a major trend has been recognized. The general trend consists of a narrow belt of predominantly moderate sized earthquakes beneath the Lesser Himalaya just south of the Higher Himalayan front (Ni and Barazangi, 1984) where all available fault-plane solutions indicate thrusting (Fig 4). The great Himalayan earthquakes, however, occur along the basal décollement beneath the Siwalik and Lesser Himalaya. The focal depth for the Himalayan earthquake varies from 10-20 km. Figure 4: Focal mechanism solution of major earthquakes in Himalaya. Dotted line shows contour of 5000 m. Note that north of 5000 m altitude earthquakes are of normal type whereas thrust type to the south.

Historical records indicate that the Kathmandu valley, where the capital city is located, has experienced large earthquakes in the past centuries. Major damage of probable seismic origin is reported to have occurred in 1255, 1408, 1681, 1803, 1810, 1833 and 1866 (Chitrakar and Pandey, 1986). Some of these events might be related to the repetition in the past of the 1934 Bihar-Nepal earthquake. That might be the case in particular for the 1833 earthquake (Bilham, 1995). Most of the others are probably related to smaller magnitude earthquakes that would have occurred close to the Kathmandu valley. National

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DEEPAK CHAMLAGAIN Seismological Centre (NSC) under the Department of Mines and Geology has been continuously monitoring the earthquake events since 1978. NSC documentation shows that between 1994 and 1999, the average frequency of earthquakes having magnitude between two and less than 5 was approximately 10 per day, magnitude 6 and less than 7 was 1 in per 6 years. Similarly, total number of earthquakes of magnitude 2 to less than 7 between 1994 and 1999 were approximately 700, 900, 1500, 1700, 2200, and 1600 respectively (Upreti, 2001). Although the general trend shows that number of earthquakes is increasing in Nepal Himalaya (Fig 5), no very large earthquake seems to have struck FarWestern and Western Nepal over the past few centuries. Figure 5: Number of Earthquakes (Ml >4) occurring in Nepal between 1994 and 2007. Data from National Seismological Centre, Kathmandu.

Intense microseismicity and moderate earthquake events throughout the Nepal Himalaya cluster along the foothills of the Higher Himalaya (Pandey et al., 1995). It makes an E-W trending zone as shown in Fig 6a. In western Nepal it lies between 80.5° E and 82.5°E whereas in central Nepal it is bounded between longitudes 82.5°E and 86.5°E. The eastern Nepal cluster is characterized by higher level of events between 86.5°E and 88.5°E. The projection of microseismic events along the structural crosssection shows noticeable change in shape and location of the clusters between central and western Nepal (Fig 6b). In central Nepal the cluster has a rounded form and is located in the vicinity of the flat-ramp transition of the MHT. The cluster in western Nepal shows an elongated form and is nearly horizontal. These clusters reflect stress accumulation in the interseimic period, during which the décollement beneath the Higher Himlaya probably remains locked and mid-crustal ramp acts as a geometrical asperity (Pandey et al., 1995).


EARTHQUAKE SCENARIO AND RECENT EFFORTS TOWARD EARTHQUAKE RISK REDUCTION IN NEPAL Figure 6a: Intense microseismicity (monitored between 1994 and 2005) in Nepal Himalaya, shown by circles, tend to cluster south of the Higher Himalayas.

Figure 6b: Projection of earthquake in crustal cross-section section. A-A' for western Nepal and B-B" for central Nepal. Modified from DMG, 2006.

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Efforts Toward Earthquake Risk Reduction: A Nepalese Scenario Nepal has been celebrating October 8 as an International Strategy for Disaster Reduction (ISDR) day from the beginning to increase public awareness on various natural, manmade and technological disasters. The mission of ISDR is to build disaster resilient communities by promoting increased awareness of the importance of disaster reduction as an integral component of sustainable development, with the goal of reducing human, social, economic and environmental losses due to natural hazards and related technological and environmental disasters. In the light of this mission and to meet the objectives stated in the ISDR and Hyogo Framework for Action (ISDR, 2005), a number of important initiatives were taken by government as well as Non-Government Organizations (NGOs). The initiatives and the results achieved thereby are summarized in the following sub-sections.

Hazard Mapping and Vulnerability Assessment of Buildings Despite the urgent need of hazard assessment of the country, Nepal has not taken enough initiatives to understand the level of seismic hazard. Since the establishment of the NSC in 1978, Nepal has documented good number of data on earthquakes both locally and regionally. It has also done important research work on seismotectonics (Pandey et al., 1995 and 1999) of the Nepal Himalaya but never properly considered about hazard mapping. The main reasons behind this are first lack of human resource, and second improper use of limitedly available human resources. Despite the various technological limitations, Pandey et al. (2002) has prepared a seismic hazard map for territory of Nepal (Fig 7). In this map, the districts prone to the various intensities of hazards are clearly shown. Apart from these, Japan International Cooperation Agency (JICA) and National Society for Earthquake Technology- Nepal (NSET) have also carried earthquake risk assessment and management works in Kathmandu Valley. To the date most of the risk and hazard assessment works have been done for either Kathmandu Valley or few urban areas outside the valley. This scenario directs us to conclude that most of research works on earthquake risk reduction is limited in the urban areas of Nepal. Unfortunately, policy maker, politician and professional rarely made use of such important resources while drafting development plans for the country. There are many examples of disasters that completely damaged infrastructures like bridge, buildings etc. incurring loss of million of rupees due to ignorance of engineers to possible natural disasters. Although Nepal has good sorts of data base on population and housing acquired through national census in every ten years, government has not started any vulnerability assessment program for the existing building even in urban areas.


EARTHQUAKE SCENARIO AND RECENT EFFORTS TOWARD EARTHQUAKE RISK REDUCTION IN NEPAL Figure 7: Seismic hazard map of Nepal. Modified after Pandey et al. (2002). Bedrock peak ground horizontal acceleration is calculated for five hundred years return period. Contour interval is 50 gals.

Legislation Nepal Government has passed Natural Disaster Relief Act (NDRA) in 1982 AD which was amended twice in 1989 and 1992 AD. Prior to the enactment of the NDRA, natural disasters were treated when they occurred. There were no pre-disaster preparedness plans and post-disaster mitigating measures. Disasters were often treated as acts of God and as a scourge. Nepal had no well-structured disaster policy and relief and rescue works were carried out on an ad hoc basis, mainly as a humanitarian and social services. Following the enactment of the NDRA a general awareness was created that, although disasters cannot be prevented we can prepare for them and mitigation measures are possible. The act of preparedness has the beneficial effect of reducing the risk of disaster and minimizing its effects and the cost of post-disaster relief and rehabilitation activities. The NDRA made provision for the formation of a 25-member Central Disaster Relief Committee under the chairmanship of the Minister for Home Affairs (Fig 8). It notes the functions of this committee in relation to natural disasters. It also empowers the government to constitute regional, district, and local level natural disaster relief committees by publishing a notification in the Nepal Gazette. The functions of these committees are detailed in the Act. The Act further provides for the setting up of natural

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DEEPAK CHAMLAGAIN disaster aid funds at the central, regional, district, and local levels by authorizing the committees at different levels to use such funds in relief operations. Figure 8: Disaster Relief Committee of Nepal.

National Plan Nepal has no separate action plans for each type of disaster. Nepals' National Action Plan 1996 (MoHA, 1996) is only a consolidated and comprehensive plan which addresses all the phases of a disaster. Sectoral policies and plans address disasters relating to floods and landslides. The Water Resources Strategy (WRS) 2002, National Water Plan (NWP) 2005, and Water Induced Disaster Management Policy (WIDMP) 2006 are sectoral plans and policies that take care of water induced natural disasters e.g. floods and landslides at national level. Nepal Government has not formulated separate action plan for earthquake disaster, although entire territory is very much vulnerable to earthquake disaster. However, local government like municipalities has recently initiated awareness and preparedness programs through community workers coordinating NGO and INGOs. Responding to the UN global call for disaster reduction, the Government of Nepal formed an IDNDR National Committee under the chairmanship of the Minister for Home Affairs. Since the previous efforts were concentrated on rescue and relief operations following disaster events, the IDNDR National Committee felt the need to prepare a practical and effective action plan on disaster management, focusing on disaster preparedness and has formed four core groups of experts, administrators, academicians, and security personnel to draw up a national action plan. The Government of Nepal approved the National Action Plan on Disaster Management in


EARTHQUAKE SCENARIO AND RECENT EFFORTS TOWARD EARTHQUAKE RISK REDUCTION IN NEPAL Nepal on February 18, 1996. It has four sections: (i) disaster preparedness, (ii) disaster response, (iii) disaster reconstruction and rehabilitation, and (iv) disaster mitigation. In addition, several municipalities have taken up review of relief manuals and preparation of calamity preparedness guidelines to suit local needs and geo-climatic conditions. They have prepared their own action plans coordinating NGOs and INGOs.

Strengthening of Information Technologies The Ministry of Home Affairs, which is the nodal Ministry for Disaster Management in Nepal, involves mainly on relief and rescue work during disaster. In addition, it also engages on information management system (collection, storage, retrieval and dissemination of information) in managing the situation caused by natural disasters. The Department of Water Induced Disaster Prevention (DWIDP) under the Ministry of Water Resources is working on water induced disasters using the various state-of-the-art technologies, namely Remote Sensing, Geographical Information System (GIS), Global Positioning System (GPS), and Computer Modeling. Similarly, National Seismological Centre is also actively working on monitoring earthquake events and crustal deformation by using modern technologies in collaboration of foreign government organizations and universities. Active and ongoing efforts are being made for modernizing the organization so as to make them more effective and community friendly.

Human Resource Development Nepal is still lacking on human resource development on disaster management. NGO/INGOs are frequently conducting training on disaster management for people of different level including professional and engineers. Scattered lessons can be found in school textbooks mainly on environment and science texts. Since students can work as propagators to disseminate information about natural disasters at home and in the community, Disaster Management Education (DME) should be introduced in schools curriculum in more organized form. Keeping this in priority, school level curriculum is being prepared under the supervision of experts. Purbanchal University has already introduced disaster management course in Bachelor Level of civil engineering and architecture. Khwopa Engineering College, a community college run by Bhaktapur Municipality, has been offering Master Course on Earthquake Engineering since 2005. The first batch of this course already received their degree. The Master's level curriculum on disaster management prepared by the Institute of Engineering (IoE), Pokhara University can be introduced in engineering colleges with the introduction of an appropriate training of teachers. In addition, investments are being made on building capacity of NGOs, and

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DEEPAK CHAMLAGAIN Community-Based Organizations (CBOs) for working with the community as well as with the government. A considerable number of national and international conferences, symposia and workshops were organized and proceedings published by number of institutions and learned societies and organizations on various subjects related with disaster mitigation, prevention and management. In this regards efforts made by Nepal Geological Society is key to dissemination of research finding and interaction among scientists from different countries on disasters. NSET has been regularly organizing mason training for earthquake resistant building. It also provides training of trainer (ToT) to civil engineers so that they can instruct the semi-skilled technician of construction works.

Upgrading and Strengthening of Seismological Network NSC at Department of Mines and Geology (DMG) is collaborating with many scientists from all over the world to understand the cause and devastating effect of the earthquakes, and to help mitigate the ensuing destruction. The effort started in the eighties with Laboratoire de Geophysique Applique (LGA) Paris University, and the deployment of an array of short period vertical seismometers at Phulchoki around the Kathmandu Valley. After the 1988 Udayapur earthquake, a priority was given to expansion of the national network of seismic stations to cover the whole territory of Nepal. As a result, the National Seismological Network project was launched in 1991, in collaboration with Laboratoire de Geophysique (Department Analyse Surveillance Environment, France) with, as an objective, the deployment and operation of a nationwide seismic network designed for early warning. Deployment was completed in 1994, and the NSC is now operating twenty short-period 1-component stations that are telemetered in real-time (Fig 9). Recently, it has networked one long period and broadband station. Data from seismic stations west of Pyuthan are telemetered to the Regional Seismological Centre at Birendranagar, Surkhet and the data from remaining stations east of Pyuthan are telemetered to the National Seismological Centre in Lainchaur, Kathmandu. More recently, the seismic network was complemented with continuously recording GPS stations (Fig 9) as part of a collaborative project with the Laboratoire de Geophysique (France) and the Caltech Tectonics Observatory (Californian Institute of Technology, USA). The first three stations were deployed in 1997 and the geodetic network now consists of thirteen stations. The data from these networks have revealed key information on Himalayan seismicity and crustal deformation, providing firm basis for seismic hazard assessment in the Nepal Himalaya. The network provides routine information on global seismicity, contributing to worldwide monitoring and early warning in case of damaging earthquakes.


EARTHQUAKE SCENARIO AND RECENT EFFORTS TOWARD EARTHQUAKE RISK REDUCTION IN NEPAL Figure 9: Network of seismic and global position stations in Nepal.

Enforcement of Building Code Regarding safety of buildings and structures, the first pre-requisite is to develop appropriate building codes. History of building code development in Nepal is very short. The Bureau of Standards and Metrology has initiated a process for defining the draft Building Code as a Nepal Standard. Several of the 22 documents prepared for the National Building Code, which focuses on seismic safety, were accepted as Nepal Standards. The National Building Code, 2003 of (NBC), enforced in 2003 following the approval of the Government on July 28, 2003, was brought in to mitigate the effects of earthquakes in urban areas and as a measure towards earthquake preparedness (Pokharel 2005). It has been structured in the four different hierarchies, e.g. code for the state-of-the- art- building (Class I), codes for professionally engineered structured (Class II), codes for non-engineered building which are small building which can be designed with Mandatory Rule of Thumb (Class III) and guidelines for rural building (Class IV). NBC urges the municipal authorities to strengthen the current building permit process so that code compliance will be mandatory for all new constructions in urban areas. However, there are few municipalities, which are strictly following the

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DEEPAK CHAMLAGAIN National Building Code for construction. The effective implementation of these codes could only be ensured through their mandatory provision in the building By-laws. This is where action is lacking and the issue has been raised with the concerned authorities.

Public Awareness Public awareness is one of the efficient ways to reduce risk of earthquake. In this regard, though efforts are unevenly distributed, Nepal has done significant works through the involvement of government organization, NGOs, INGO, Community Based Organization (CBOs) and academic institutions. A number of brochures, hand book, pictorial book, illustrated story book, pamphlet, booklet, poster, and fliers with regard to earthquakes have been printed and distributed to the school student, lower level technical personnel, as well as the general people of the disaster prone regions, on a large scale. Some of the important works carried out to increase public awareness on earthquake in Nepal are described briefly below.

Pictorial Book/ Popular Articles Nepal Red Cross Society (NRCS, 2006) has published pictorial book on earthquake with the financial support of United Nations Children's Fund (UNICEF) and European Commission. This is prepared for the non-technical and general people and provides information on scientific meaning of earthquake and peoples' misconception about earthquake. It has nicely presented earthquake scenario in Nepal along with possible effect, risk, and consequences of earthquake. Preparedness required to minimizing earthquake risk is mentioned in pictorial form so that general public can easily understand. It also describes detail procedures to be followed pre, post and during earthquake. Some of the pictorial descriptions are shown in figure 10. The newspapers and magazines usually do not show interest in publishing popular articles about mitigation and hazard reduction, however, they give extensive coverage after earthquake takes place. Despite this situation few numbers of popular articles have been written about earthquakes daily news paper (e.g. Chamlagain, 2008a,b). However there are many specialized articles in research journals and conference proceedings, which are not available to the public.


EARTHQUAKE SCENARIO AND RECENT EFFORTS TOWARD EARTHQUAKE RISK REDUCTION IN NEPAL Figure 10: Extracts from the pictorial book showing (a) Misconception on earthquake (b) Meaning of earthquake (c and d) Effect of earthquake (e) Earthquake risk (f) Training cum drilling works to increase preparedness (g) Earthquake preparedness (h) Relief and rehabilitation works aftermath of the earthquake disaster.

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Guide Book/ Illustrated Story Book NSET (1999), with the financial assistance of U.S. Agency for International Development (USAID), has brought earthquake preparedness handbook in Nepali language. This text mainly focuses on the structural safety of the building pre, during and post earthquake phases. List, use and storage of emergency materials like medicines, food, drinking water, rescue equipment, are also provided in the annex section. The safe places in and out side of the building are explained in the pictorial form so that general people can easily understand and follow the instructions. Similarly, Lalitpur Sub-Metropolitian City (2006) with the aid of UNICEF and European Commission made available guide book entitled as earthquake preparedness planning for family. This has greatly improved preparedness capacity of the residents of the metropolitans. To make understand people about possible impacts of devastating earthquake like 1934 Bihar-Nepal earthquake, NSET and Geohazard International (2007) published dramatized pictorial book. Such books were fruitful to aware people about the possible damage of devastating earthquake to housing, transportation, medical facilities, food and water supply, communication, and education. NSET has also distributed seismic pictorial story book to instruct and encourage mason for the earthquake resistant building construction.

Pamphlet, Poster, and Fliers Similarly varieties of pamphlet, booklet, poster, and fliers on various natural disasters were developed and distributed to general public mainly in urban areas. NRCS has disseminated various types of poster, pamphlet and fliers to disaster prone rural and urban areas. From the government side, Department of Urban Development and Building Construction distributes pamphlets on earthquake safety, instruction on earthquake resistant construction of various buildings, and retrofitting of existing buildings. These materials are valuable for the mason and general public where required technical service is far from their access. NSET also distributed poster displaying earthquake induced cracks in buildings to show inherited risk and danger of the cracked buildings. Similarly, NSET distributed pamphlets on earthquake-safe health facilities. Various local NGOs and CBOs are actively working in disaster preparedness and public awareness through distribution of education tools.

Radio/Television Programms Because of advancement in media technology and affordable price, nowadays, poor people also have access to electronic media like radio and television. In this modern age of electronic media, radio and television programs on natural disasters are very much


EARTHQUAKE SCENARIO AND RECENT EFFORTS TOWARD EARTHQUAKE RISK REDUCTION IN NEPAL effective to create public awareness. Considering their effectiveness, United Nation Development Program (UNDP) is broadcasting short programs on awareness and preparedness through radio and television. NSET is airing radio program "Bhukampa Gatha" daily and weekly through various frequency modulation (FM) radio station. To increase public awareness Nepal is celebrating Earthquake Safety Day on second day of Magh of Nepali Calendar. It generally falls on 16 or 17 of January. Video films on earthquake are also shown during earthquake safety day to introduce people about earthquake, its causes, effects, damage and destruction. For the above mentioned activities, Nepal Government has been receiving significant financial and technical supports from various donor agencies like, UNDP, UNICEF, JICA, USAID, European Commission, and Lutheran World Federation (LWF) etc.

Challenges and Shortcomings in Ongoing Efforts Although country has improved greatly to increase public awareness and level of preparedness on earthquake hazard particularly in urban areas. There are still shortcoming and many sectors that must be dealt with appropriate policy and programs. Following are some the issues to be considered for earthquake risk reduction.

Mapping and Quantification of Earthquake Hazard As mentioned above NSC has prepared preliminary seismic hazard map of the entire territory of Nepal. This map can provide just first order assessment of seismic hazard. Effect of surface geology on local ground motion has not been included in the map. Therefore, more precise map incorporating all essential parameters should be prepared for reassessment of earthquake hazard level of the country. For this, there should be collaborative efforts in research activities of all government, NGOs and INGOs with the academic institutions. Population census has been carrying out in every ten years; data on housing is readily available. Therefore, retrieval of these data and their analysis has become very easy. These data now should be used for the vulnerability analysis of the existing building and other structures to minimize risk of earthquake.

Disaster Preparedness and Preventive Measures Nepal has noticeably improved on earthquake awareness in the urban communities through coordinated efforts of both government and non-government organizations. However, people from the remote areas of the country do not have enough opportunity to participate such programs. Taking lesson from the past earthquake like, 1988 Udayapur earthquake in eastern Nepal, proper awareness and preparedness programs should be

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DEEPAK CHAMLAGAIN launched through out the country. As we know that earthquakes do not kill people, but the structures do therefore our efforts should focus to make our structures strong enough to withstand the impact of probable earthquakes. In Nepal land use restriction is not provided in town planning laws or master plan rules. Also many municipal laws are silent about the earthquake safety requirement of the building. Further, town planning acts are not strictly implemented. The result is that cities are expanding in all direction occupying even hazard prone areas, and unsafe buildings are being constructed. Although some municipalities have introduced national building code as a mandatory requirement for construction, still many urban areas have not introduced it. Therefore, government should enforce National Building Code in all types of construction through out the country.

Research, Education and Training Research, education and training in earthquake engineering have recently been started by Khwopa Engineering College in Bhaktapur through the PG Department of Earthquake Engineering. It has introduced a Master degree program on earthquake engineering. This certainly contributes to development of human resources in earthquake engineering and increase national capacity on design and construction of earthquake resistant structures. NSC has documented very good amount of earthquake data and made good progress on seismotectonics of the Nepal Himalaya. However, there are very little works on paleoseismology (e.g., Chamlagain et al., 2000; Kumahara et al., 2001). Because recurrence interval is very important for seismic hazard mapping, more funding should be allocated for paleoseismology. Similarly, preparation of seismotectonic atlas of Nepal including earthquake data, stress field data, gravity data, magnetic data, geological faults, neotectonic data and geodetic data is very urgent for the preparation of precise seismic hazard map of Nepal.

Revision on National Plan and Acts It is well-known that each disaster has its own nature of occurrence, effects, consequences, preparedness, and mitigative measures. Therefore, existing sole national plan should be revised and formulate separate national plan for each disaster. Further, National Action Plan for Disaster Management 1996 gives details of the plan at the national level. The Plan is executed in all 75 districts of the country through District Disaster Relief Committee (DDRC) and other government agencies at the centre. The districts, therefore, need longterm natural disaster preparedness plans for implementation. However, plans have been made for five pilot districts only with the support of the United Nations Office for Cooperation in Humanitarian Affairs (UN/OCHA). Of these five plans, only the district


EARTHQUAKE SCENARIO AND RECENT EFFORTS TOWARD EARTHQUAKE RISK REDUCTION IN NEPAL plan for Chitwan has been formally launched by the government. It is, therefore, urgent to prepare and lunch district plans of remaining districts for natural disaster preparedness. In the absence of proper plans, the DDRCs are presently engaged only in post-disaster activities when disasters occur. Hazard maps of the most susceptible areas have not yet been prepared for all categories of natural disaster such as floods, landslides, mass wasting areas, and areas vulnerable to frequent earthquakes. In the absence of such maps, plans and programs cannot be implemented to mitigate natural hazards. As a result, valuable lives and property are being lost every year. Lack of human and financial resources are the main reasons for not implementing some of the key activities in the National Action Plan formulated on the occasion of IDNDR. Because of political instability and insurgency researchers have failed to carry out field survey work and construction activities in disasterprone areas of the country. Inadequate policies and a weak legal environment are the biggest impediment to disaster management in Nepal. Development of an effective institutional mechanism has always been promoted, but without success. Absence of an organization at the highest level that could provide intellectual and administrative leadership is a serious gap in Nepal. Therefore, for the proper management of natural disasters, our efforts should focus to acquire financial resource, political commitment, and proper human resource with sound disaster management plan.

Summary and Suggestions The foregoing discussion on seismotectonics, active tectonics and seismicity of Nepal Himalaya has clearly shown that Nepal is one of the earthquake prone areas on the globe. Basically, the Main Himalayan Thrust, which is exposed to the frontal part of the Himalaya as a Main Frontal Thrust, is generating major earthquakes posing threats to thousands of people living in the northern tip of the Ganga basin. In the last two decades Nepal has shown good progress on seismotectonic research, however, paleoseismological study has not been carried out extensively. Therefore, our efforts should focus paleoseismological investigation to understand recurrence interval of devastating earthquake, which are directly useful to hazard assessment. The efforts initiated by Nepal Government, NGO, INGO and CBO are encouraging but access to these programs are limited to people of urban and semi urban areas. Therefore earthquake risk reduction programs should also be launched remote areas. For the better management of earthquake risk government policy and plan should spotlight the following: (i) Investment on research (e.g., seismotectonics and paleoseismology), education, training, and human resource development in the area of earthquake seismology and engineering.

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(ii) Enhancement of the technology of earthquake prediction methodologies and forecast system. (iii) Mapping of the earthquake hazard both urban and rural areas in large scale and linking of these maps with the development plan and activities. (iv) Establishment of Earthquake Risk Evaluation Centre (EREC) of highly educated scholars aiming to entire work from earthquake early warning system to risk management phase. (v) Coordination of financial and legal institution, insurance companies, disaster related organization to formulate disaster related insurance policy. (vi) Formation of institutional network of all organizations working on disasters to share their knowledge and experience. (vii) Promotion of public awareness and preparedness programs intensively throughout the country.

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