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Multi-Jurisdictional Risk Assessment As described in the previous section on Profiling Hazards, each of the participating jurisdictions evaluated the hazards identified for the planning area. Each jurisdiction was asked to score the hazards profiled based on the methodology in Attachment III-1 for the following categories: --Historical Occurrence --Probability --Vulnerability --Maximum Geographic Extent --Severity of Impacts --Speed of Onset Each jurisdiction was asked to score the hazards based on their own local perspective and to note any additional information for the profile specific to its jurisdiction. The individual community scores were combined and averaged to provide the basis for determining the ranking and priority of the identified hazards for the whole planning area. The following individual jurisdiction risk assessments provide comparable data regarding population and land area. A geographic summary notes specific features that distinguish the jurisdiction from the planning area as a whole. The hazard priority provides a list of the top ranking hazards based on the hazard profile scoring and adjusted as needed based on local experience. This section also explains any differences in hazard ranking compared to the planning area. Finally, the Critical Facilities section summarizes structures identified as important to the jurisdiction that may be vulnerable to hazard impacts. The specific lists of Critical facilities were mapped in relation to the 100-year floodplain as presented in Map_(insert map reference as appropriate_____ Andalusia --2000 Census population 1,050 -- 0.7% total County population --Ranks 11 of 16 jurisdictions in size --Land area 1.17 sq. miles --0.2% total planning area --Rank 12 out of 16 jurisdictions Geography: Andalusia is located in the lower southwest portion of Rock Island County on the Mississippi River below the confluence of the Rock River. Because of the Mississippi River islands in that location, Andalusia is not on the main Mississippi River channel, but on the backwater area called Andalusia Slough. Most of the older developed area is north of Illinois Route 92. Most of this area is part of the Mississippi River flood plain, but protected by levees. South of Route 92 begins some of the river bluff area with more slopes and ravines and timbered areas. It is noted that a new residential addition is being developed in an area with some slope issues. However, existing planning mechanisms provide subdivision and site review along with regulatory erosion controls. Hazard priorities: Severe Storms (combined) River Flood Tornado Dam or Levee Failure Extreme Heat/ Drought Andalusia rates Severe Storms (Combined) in the same position as the planning area as a whole. The frequency of occurrence in the planning area and the related problems triggered by this hazard, such as power outages, make this a priority hazard for many of the jurisdictions in the planning area. Unlike the planning area as a whole, Andalusia replaces the Severe Winter Storms hazard with River Flood. Obviously with substantial river frontage this is a major concern. Flood protection has been provided by a levee. This levee was constructed by the U.S. Army Corps of Engineers and has been maintained by the Village, but it no longer meets current requirements for FEMA flood plain certification. Because the levee is structurally deficient in levee base size and materials, it will probably require total reconstruction to meet a certifiable level, a long- term project. For this reason, Andalusia has included Dam and Levee Failure as a priority hazard, while this is ranked lower for the planning area as a whole. The Tornado and Extreme Heat hazards are also ranked as most important hazards, similar to the first priority ranking for the planning area. Andalusia scored Drought the same as Extreme Heat, probably for the relationship between the two hazards in terms of impact to water supply and wildfire potential. Critical facilities: Andalusia listed six structures. These are primarily local government facilities, including the Village Hall, water, maintenance, police and fire. Also included is the U.S. Post Office. Because of the geography of the area, all of these facilities are in the flood plain but for the levee protection. It is noted that the well heads for the Village’s water supply are within the floodplain. In the event of a flood, the water source could be super chlorinated for a time. However, doing this for a longer period of extended flood conditions could burn our pump equipment. The long-term solution would be to move the well heads to a better location. This will entail realigning the water distribution system in relation to the water tower. Carbon Cliff --2000 Census population 1,689 --_1.1% total County --Ranks _8___ of 16 jurisdictions in size --Land area 2.08sq. miles --___0.4%__% total county area --Rank _9___ of 16 jurisdictions Geography: The Village of Carbon Cliff is on the east end of the peninsula of land between the Mississippi and Rock Rivers that characterizes the central portion of Rock Island County. The northwest corner of Carbon Cliff is about two to three miles from the Mississippi River, but there is a small portion of Rock River frontage to the south and east of the Village. Illinois Route 84 separates the bluff line from the flood plain. Unlike the Mississippi River towns in the upper portion of the county, the bluff line is to the west of Route 84 and the land to the east is part of the Rock River floodplain. With historic development based on mining and the railroad, Iowa Interstate Railroad tracks cross the Village from northwest to southeast. The oldest development is between the bluff line and the railroad tracks and the 100-year flood plain line meanders through this portion of town. The elevation toward and east of the railroad tracks declines even more so that the Village is surrounded by wetlands on the north and east sides. Newer residential development is in the bluff area where there are also two unnamed tributary creeks with accompanying floodplains. Heavy rains can cause flash flooding from the bluff area and add to the drainage problems on the lower side of town. Also on this lower side, historic coal mine sites have been mapped that contribute to the Village’s name. In an Illinois Route 5 Corridor Study done by bi-State Regional Commission in 1986, one mine was described as having extensive shafts that run in several directions of a couple of blocks. Clay was also mined, but there is no documentation of a mine site. Priority hazards: Severe Storms/River Flood Flash Flood Severe Winter Storms Land Subsidence/Extreme Heat Tornado Priority hazards for Carbon Cliff were adjusted in rank from the way the hazard profiles were initially scored. Based on local experience, the hazards of Severe Storms (Combined) and River Flood moved to the top of the list. The Severe Storms (Combined) share the same ranking as the planning area as a whole. However, for Carbon Cliff River Flood was scored equally high. With the flood plain and wetlands described in the Geography section above, severe storms may produce heavy rains that contribute to river-related flooding. Flash floods also rank higher than for the planning area as a whole. With run off from the bluff area, it is easy to see why stormwater drainage is a major issue for the Village. Carbon Cliff includes most of the same hazards that the planning area ranked as first priority, but in different order. An exception is Land Subsidence, which scored equally with Extreme Heat for Carbon Cliff to put it in the top ranking. A history of mining in the Village as described makes subsidence an issue of concern. Incidents of Extreme Heat can happen as much as annually within the planning area. Tornado also is a first priority hazard for the planning area that Carbon Cliff includes in its top-ranked list. Critical Facilities Carbon Cliff listed 20 structures in its inventory of community assets. Sixteen of these are noted as critical and include village services and infrastructure, such as village Hall, Fire, Police, and water and sewer infrastructure. Two school buildings are included as critical facilities, as are the railroad tracks that pass through town. Critical facilities located east of Route 84 may be in or near the 100-year flood plain. Two housing areas were noted for vulnerable populations. Two commercial convenience outlets were listed as other important facilities, providing local services and economic continuity after a disaster. Coal Valley --2000 Census population 3,606 --_2.4___% total County --Ranks _7___ of 16 jurisdictions in size --Land area 2.76 sq. miles (includes portion in Henry County) --___0.5__% total planning area --Rank __7__ of 16 jurisdictions Geography: The Village of Coal Valley ranks at about the middle of the jurisdictions participating in this planning process, both in terms of population and land area. With developed land within a bluff line south of the Rock River, Coal Creek and Shaffer Creek and bluff slopes provide conditions for the occurrence of flash flooding. U.S Routes 6 and 150 go through Coal Valley, with I280 just out side the Villages northern border along the Rock River. Historic coal mine sites that name Coal Valley are concentrated in and around the downtown area. However, no information about structural damage from land subsidence due to mine sites could be found for even the oldest of buildings, that anyone can recall at this time. A coal mine found more recently in development along Route 150 in the 300 block east was filled in. The existence of coal mine sites in the vicinity of the Quad City International airport will be a concern for future development for both Coal Valley and that portion of the City of Moline that crosses the Rock River to the west.