COOK ISLANDS Public Disclosure Authorized
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PACIFIC CATASTROPHE RISK ASSESSMENT AND FINANCING INITIATIVE Public Disclosure Authorized COOK ISLANDS Public Disclosure Authorized SEPTEMBER 2011 COUNTRY RISK PROFILE: COOK ISLANDS The Cook Islands are expected to incur, on average, about 5 million USD per year in losses due to earthquakes and Public Disclosure Authorized tropical cyclones. In the next 50 years, the Cook Islands have a 50% chance of experiencing a loss exceeding 75 million USD and casualties larger than 130 people, and a 10% chance of experiencing a loss exceeding 270 million USD and casualties larger than 200 people. Public Disclosure Authorized BETTER RISK INFORMATION FOR SMARTER INVESTMENTS COUNTRY RISK PROFILE: COOK ISLANDS POPULATION, BUILDINGS, INFRASTRUCTURE AND 166° W 164° W 162° W 160° W 158° W 0 1 2 4 S Aitu- 0 150 300 600 ° Arutanga CROPS EXPOSED TO NATURAL PERILS 8 taki Kilometers Kilometers An extensive study has been conducted to assemble a S ° 0 comprehensive inventory of population and properties at 1 Atiu S Mangaia risk. Properties include residential, commercial, public and ° 2 1 0 12 4 industrial buildings; infrastructure assets such as major ports, S 0 1 2 3 airports, power plants, bridges, and roads; and major crops, ° 4 1 Buildings such as coconut, palm oil, taro and many others. Avarua Rarotonga S Residential Public ° 6 1 Commercial Other TABLE 1: Industrial S ° Summary of Exposure in Cook Islands (2010) 8 1 Atiu General Information: Aitutaki S ° 0 Total Population: 19,800 2 Rarotonga Mangaia S GDP Per Capita (USD): 12,330 ° 2 2 Total GDP (million USD): 244.1 Cook Islands 0 2 4 8 Asset Counts: Figure 1: Building locations. Residential Buildings: 8,357 166° W 164° W 162° W 160° W 158° W 0 1 2 4 S Aitu- Public Buildings: 503 0 150 300 600 ° Arutanga 8 taki Kilometers Commercial, Industrial, and Other Buildings: 1,742 Kilometers S ° 0 All Buildings: 10,602 1 Atiu S Mangaia Hectares of Major Crops: 6,390 ° 2 1 012 4 Cost of Replacing Assets (million USD): S 0 1 2 3 ° Buildings: 1,296 4 1 Building Replacement Cost Density Infrastructure: 118 (million USD / km^2) Avarua Rarotonga S ° 0 - 0.5 1 - 5 15 - 20 6 Crops: 8 1 0.5 - 0.75 5 - 10 20 - 30 0.75 - 1.0 10 - 15 S Total: 1,422 ° 8 1 Atiu Government Revenue and Expenditure: Aitutaki S ° 0 Total Government Revenue 2 Rarotonga Mangaia (Million USD): 86.9 S ° 2 (% GDP): 35.6% 2 Cook Islands 0 2 4 8 Total Government Expenditure Figure 2: Building replacement cost density by district. (Million USD): 77.9 (% GDP): 31.9% 166° W 164° W 162° W 160° W 158° W 0 1 2 4 S Aitu- 0 150 300 600 ° Arutanga 8 taki Kilometers 1 Data assembled from various references including WB, ADB, IMF and The Kilometers S Secretariat of the Pacific Community (SPC). ° 0 2 The projected 2010 population was trended from the 2006 census using 1 Atiu estimated growth rates provided by SPC. Land Cover / Land Use S Mangaia ° 2 1 Cassava Other Plantation 0 12 4 Coconut Crops Rice S Coconut Forest Sand Bay Table 1 summarizes population and the inventory of buildings, 0 1 2 3 ° 4 Grass Land Forest infrastructure assets, and major crops (or “exposure”) at 1 Nut Tree Settlement Avarua Rarotonga S Open Land Sugarcane risk as well as key economic values for the Cook Islands. It is ° 6 Orchard Taro 1 estimated that the replacement value of all the assets in the Other Unknown Crops Palm Oil Water S Cook Islands is 1.4 billion USD of which about 91% represents ° 8 buildings and 8% represents infrastructure. 1 Atiu Aitutaki S ° 0 2 Rarotonga Figures 1 and 2 illustrate the building exposure location and Mangaia S ° replacement cost distribution, respectively. The footprints of 2 2 0 2 4 8 almost 10,000 of the approximately 11,000 buildings shown in Cook Islands Figure 1 were digitized from high-resolution satellite imagery. Figure 3: Land cover/land use map. More than 5,000 of such buildings, almost all in the main 2 September 2011 COUNTRY RISK PROFILE: COOK ISLANDS island of Rarotonga and the rest in the island of Aitutaki, were The Cook Islands are situated in a relatively quiet seismic area, also field surveyed and photographed by a team of inspectors but is surrounded by the Pacific “ring of fire,” which aligns deployed for this purpose. Figure 3 displays the land cover/ with the boundaries of the tectonic plates. These boundaries land use map that includes the location of major crops. The are extremely active seismic zones capable of generating large data utilized for these exhibits was assembled, organized earthquakes and, in some cases, major tsunamis that can and, when unavailable, produced in this study. travel great distances. No significant earthquakes have been reported in recent times. However, in 1909, a tsunami with TROPICAL CYCLONE AND EARTHQUAKE HAZARDS waves up to three meters damaged bridges and crop fields in IN COOK ISLANDS Rarotonga. Figure 5 shows that the Cook Islands have a 40% The Pacific islands region is prone to natural hazards. The chance in the next 50 years of experiencing, at least once, very Cook Islands are located south of the equator in an area weak levels of ground shaking. These levels of shaking are not known for the frequent occurrence of tropical cyclones with expected to cause any damage to well-engineered buildings damaging winds, rains and storm surge between the months and infrastructure assets. of October and May. In the South Pacific region from the equator to New Zealand in latitude and from Indonesia to 166° W 164° W 162° W 160° W 158° W 0 1 2 4 S Aitu- 0 150 300 600 ° Arutanga east of Hawaii in longitude, almost 1,000 tropical cyclones 8 taki Kilometers Kilometers S with hurricane-force winds spawned in the last 60 years, with ° 0 1 Atiu an average of about 16 tropical storms each year. The Cook S Mangaia Islands affected by devastating cyclones multiple times in ° 2 1 0 12 4 the last few decades. For example, in 1997, tropical cyclones S 0 1 2 3 ° Martin and Pam caused 22 fatalities, 19 of which were on 4 1 Manihiki Atoll alone, where wind and storm surge destroyed Avarua Rarotonga S ° 6 essentially every building on the island, incurring about 48 1 million USD in losses that crippled the local economy. More S ° 8 recently, in 2010, tropical cyclone Pat wrought widespread 1 Atiu Aitutaki S damage on the island of Aitutaki. Figure 4 shows the levels ° 0 of wind speed due to tropical cyclones that have about a 40% 2 Rarotonga Mangaia S chance to be exceeded at least once in the next 50 years (100- ° 2 year mean return period). These wind speeds, if they were to 2 Cook Islands 0 2 4 8 occur, are capable of generating severe damage to buildings, Perceived Shaking Not Felt Weak Light Moderate Strong Very Strong Severe Violent Extreme infrastructure and crops with consequent large economic Moderate/ Very losses. Potential Damage none none none Very light light Moderate Heavy Heavy Heavy Peak ACC. (%g) <0.17 0.17-1.4 1.4-4.0 4.0-9 9-17 17-32 32-61 61-114 >114 Peak Vel. (cm/s) <0.12 0.12-1.1 1.1-3.4 3.4-8 8-16 16-31 31-59 59-115 >115 166° W 164° W 162° W 160° W 158° W 0 1 2 4 Instrumental Intensity I II-III IV V VI VII VIII IX X+ S Aitu- 0 150 300 600 ° Arutanga 8 taki Kilometers Scale based upon Wald. et al: 1999 Kilometers S ° Figure 5: Peak horizontal acceleration of the ground (Note: 1g is equal to the 0 1 Atiu acceleration of gravity) that has about a 40% chance to be exceeded at least once in S Mangaia the next 50 years. (100-year mean return period). ° 2 1 0 12 4 S RISK ANALYSIS RESULTS ° 0 1 2 3 4 1 To estimate the risk profile for the Cook Islands posed by Avarua Rarotonga S ° tropical cyclones and earthquakes, a simulation model of 6 1 potential storms and earthquakes that may affect the country S ° 8 in the future was constructed. This model, based on historical 1 Atiu Aitutaki data, simulates more than 400,000 tropical cyclones and S ° 0 2 Rarotonga about 7.6 million earthquakes, grouped in 10,000 potential Mangaia realizations of the next year’s activity in the entire Pacific S ° 2 2 0 2 4 8 Basin. The catalog of simulated earthquakes also includes Cook Islands large magnitude events in South and North America, Japan and the Philippines, which could generate tsunamis that may 0 25 50 75 100 125 150 175 200 affect the Cook Islands’ shores. Maximum Wind Speed Figure 4: Maximum 1-minute sustained wind speed (in miles per hour) with a 40% chance to be exceeded at least once in the next 50 years. (100-year mean return period). 3 September 2011 COUNTRY RISK PROFILE: COOK ISLANDS The country’s earthquake and tropical cyclone risk profiles 166° W 164° W 162° W 160° W 158° W 0 1 2 4 S Aitu- 0 150 300 600 ° Arutanga are derived from an estimation of the direct losses to 8 taki Kilometers Kilometers S buildings, infrastructure assets and major crops that are ° 0 caused by all the simulated potential future events. The 1 Atiu S Mangaia direct losses include the cost of repairing or replacing the ° 2 1 012 4 damaged assets, but do not include other losses such as S 0 1 2 3 ° contents losses, business interruption losses and losses to 4 1 Total Average Annual Loss primary industries other than agriculture.