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Reconstruction of Ica, Pisco, Chincha and Cañete, Peru, Based on Updated Hazard Maps Julio Kuroiwa Profffessor emeritus National University of Engineering and UNDP Reconstruction Program/Sustainable Cities. Peru. Proposal of a Sustainable City (SC) In view of the growing unplanned urban develop- ment taking place, in developing countries which makes cities: risky, inefficient & hostile. A proposal of a sustainable city was made, defined as: Safe, orderly, healthy, attractive, efficient, environenviron-- mentment--friendly,friendly, appreciative of its culturalcultural--historichistoric heritage and therefore, governable and competitive. Strategy to Develop a Sustainable Cities Program (SCP) Focus the SCP on the SC’s first attribute: Its philhysical sa ft(SCPfety: (SCP-1S) Carry out priority actions in the short term protecti ng life an d proper ties. Develop an urban plan based on the hazard map. The final goal is to achieve a competitive city. Hazard Map Based on the traditional microzonation methods and tec hn iques w ith a mu ltihazar d approac h. A typ ica l team has the following specialties: geology, soil mechanics, hyygyydrology/hydraulics, environment, GIS. If other specialists are needed, they are included, e.g. an expert on tsunamis, for Pisco and Tambo de Mora located on the sea shore. Team leader is usually an urban planner or architect, closer to the pppopulation’s social needs than en gineers , and better able to produce a friendly document for the next users. Statistical Data of Mexico’s Earthquakes Showing Microzonation Effects Accelerograms recorded on the coastcoast near the epicenter and in Mexico City, 300 km from the EQ. Soruce Ref. UNAM Seismic wave amplification on soft soil Ratio of acceleration on rock and Amplification of the horizontal peak on soft soils. (Ref. IdrissIdriss.. 1991) acceleration for different types of soil according to Seed, et al., 2001. ? Natural Hazard and Land Use Planning Restrictions DEGREE OF RESTRICTIONS AND CHARACTERISTICS EXAMPLES HAZARD RECOMMENDED USAGE Forces of nature are so Sectors threatened by landslides, Not permitted for urban use. strong that man-man-mademade avalanches, and sudden flows of mud Recommended for open air 1. HIGHLY constructions cannot and rocks. recreation. HAZARDOUS withstand them. Soils with high probability of (Red) Losses reach 100%. widespread liquefaction or soils that Cost benefit ratio rules out are collapsible in large proportions. its use for urban purposes. Effective damagedamage-- Strips adjacent to veryvery--highhigh hazard Detailed studies by reduction measures can sectors, but the hazard remains high. experienced specialist. be taken at reasonable Sectors where high seismic Recommendable for low- 2. HAZARDOUS costs. acceleration is expected and slowly density urban use. (Orange) become inundated. Adobe construction is not Partial occurrence of liquefaction and permitted expansive soils. Moderate natural threat. Soil of intermediate qqy,uality, with Suitable for urban use. 3. MEDIUM moderate seismic accelerations. Very Normal geotechnical studies (Yellow) sporadic flooding with little depth or required. speed. Low amplification of Flat or gently sloping land, rock or Ideal for highhigh--densitydensity urban seismic waves. compact dry soil, with high load use and the location of Very remote possibility of capaciiity. essentia l bu ildings suc h as 4. LOW hospitals, schools, police (Green) intense natural HighHigh--lyinglying non-non-floodablefloodable land, at a phenomena or gradual soil distance from cliffs of unstable hills. stations, fire station, etc. failure. Not threatened by volcanic activity or tsunamis. From Page 41. Kuroiwa, 2004. Hazard Map (1), Land Use Plan (2), and Disaster Mitigation Projects (3), for Sullana 1 Damage in La Quebrada in 1983 3 The canal freeway along La Hazard Map for Sullana Quebrada in 1998 Hazard Map (1), Land Use Plan (2), and Disaster Mitigation Projects (3), for Sullana 2 LandLand--useuse Plan for Sullana, 2000 New bridge. 3 From 11/1998 to 06/2008, 133 cities and towns with 6.4 million inhabitants have been studied. Agreements have been signed with participating local national universities: .In 10 years some 80 consultants have been trained on the jjj ob. Background: Three Disasters Between 1997 and 2007, Three Opportunities The SCPSCP--1S1S started in November 1998 when there was the need to reconstruct Peru’s NW cities devastated by El Niño 19971997--1998.1998. The SCPSCP--1S1S was expanded all over the country from Peru ’s SW, s truc k by the 2001 ear thqua ke. Following the Ica region or Pisco EQ (15/08/2007), local, regi on al & centr al gov ernm ent auth oriti es m ade th e consensual decision to use the hazard maps of the main affected cities for their reconstruction. Validation of the Hazard Maps of Ica, Pisco, Chincha and Cañete The strategy - to obtain the necessary data and to effectively reach the affected communities - was drawn up as follows: Reviewing and updating the 20012001--20022002 hazard maps, using also the advantage that the data were there in the large full-scale laboratory, i.e. the macroseismic area. Adding those towns that suffered severe damage during the 2007 event, and which had not been included in the previous studies. Intensifying the communication and coordination with local communities and authorities to capture their vision of cities for future generations, and let them know the dramatic advantage if hazard maps and disaster mitigation measures are included in their sociosocio-- economic development projects. For essential facilities VALIDATED HAZARD MAP OF ICA Short Column Failures --SCSC Short Column Long Column The left building was designed with the 1977 Seismic Code. Code. The right one with the new 1997 Seismic Code. Code.IcaIcaRegion or Pisco EQ, 20072007.. San Jose de los Molinos, Ica, Peru. VALIDATED HAZARD MAP OF CHINCHA Soil Liquefaction in Tambo de Mora Settlement of some 2.6 Lateral sppgread. The right wall has feet (0.8 m) moved to the right and towards the reader, “opening a door”. House settlement and Sand volcano floor cracks Lessons learned from El Niño 1997-98, Arequ ipa 2001 EQ an d Ica Regggion 2007 EQ, focusing those events on roads/bridges and domestic water supply, which suffered the most. Effects of El Niño 1997-98 in Peru`s NW region Erosion caused by the force of the water in Detail of the failure in the PAH due to one of the gullies crossing the PanPan-- a gully perpendicular to its axis (photo(photo American Highway PAH, in northern Peru. 1998) Failure of a bridge to the south of Trees and branches diverted the water Tumbes, Peru. El Niño 19971997--9898 and caused erosion nearby. Tumbes. 1998 Damage caused by 19971997--9898 El Niño to the PAH, in the stretch from Sullana to Desvio TalaraTalara,, Peru. Arequipa 2001 Earthquake Damage to the South PanPan--AmericanAmerican Highway and other roads caused by the 2001 Arequipa earthquake was concentrated in crossings with rivers, and where the unconfined road fills were over 13 feet (()g4m.) high. Concluding Remarks Local site characteristics: soil, geology and topography hiflhiiddhave strong influence on the seismic damage degree and its geographic distribution. Roads and domestic water distribution systems suffered the most during PeruPeru´´ss 2001 & 2007 earthquakes and El Niño 19821982--19831983 & 19971997--1998.1998. With effective application of hazard maps & earthquake resistant techniques, damage on brick masonry and reinforced concrete buildings may be reduced to less than 5% of their values. THANK YOU.