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Ramsey County Multi-Hazard Mitigation Plan, 2018 <br /> <br />Page | 75 <br /> <br />Hazus Essential Facility Loss Analysis <br />Essential facilities encounter the same impacts as other buildings within the flood boundary: structural <br />failure, extensive water damage to the facility, and loss of facility functionality (i.e. a damaged police <br />station will no longer be able to serve the community). However, none of Ramsey County’s essential <br />facilities (care facilities, fire stations, police stations and schools) included in the Hazus analysis are <br />located within the flood boundary. <br />Hazus Shelter Requirement Analysis <br />Hazus estimates the number of households that are expected to be displaced from their homes due to <br />the flood and the associated potential evacuation. Hazus also estimates those displaced people that may <br />require accommodations in temporary public shelters. The model estimates 2,015 households may be <br />displaced due to the flood. Displacement includes households evacuated from within or very near to the <br />inundated area. Of these, the model estimates 342 people (out of a total population of 508,640) may <br />seek temporary shelter in public shelters. <br />Hazus Debris Generation Analysis <br />Hazus estimates the amount of debris that may be generated by the flood. The model breaks debris into <br />3 general categories: 1) Finishes (dry wall, insulation, etc.), 2) Structural (wood, brick, etc.) and 3) <br />Foundations (concrete slab, concrete block, rebar, etc.). This distinction is made because of the different <br />types of material handling equipment required to handle the debris. <br />The model estimates that a total of 16,961 tons of debris will be generated. Of the total amount, <br />Finishes comprises 61% of the total, Structural comprises 23% of the total, and Foundation comprises <br />16%. If the debris tonnage is converted into an estimated number of truckloads, it would require 679 <br />truckloads (@25 tons/truck) to remove the debris generated by the flood. <br />Flooding and Climate Change <br />As Minnesota’s climate changes, the quantity and character of precipitation is changing. Average <br />precipitation has increased in the Midwest since 1900, with more increases in recent years. The Midwest <br />has seen a 45% increase in very heavy precipitation (defined as the heaviest 1% of all daily events) from <br />1958 to 2011 (National Climate Assessment Development Advisory Committee, 2013). This <br />precipitation change has led to amplified magnitudes of flooding. Increased precipitation may also show <br />seasonal changes, trending toward wetter springs and drier summers and falls. An example of a recent <br />year with this character was 2012, when many MN counties were eligible for federal disaster assistance <br />for drought, while others were eligible for flooding, and 7 were eligible for both in the same year (Seeley <br />M. , 2013). In 2007, 24 Minnesota counties received drought designation, while 7 counties were declared <br />flood disasters. In 2012, 55 Minnesota counties received federal drought designation at the same time 11 <br />counties declared flood emergencies. In addition, the yearly frequency of the largest storms – those with <br />3 inches or more of rainfall in a single day – has more than doubled in just over 50 years. In the past <br />decade, such dramatic rains have increased by more than 7% (MN Environmental Quality Board, 2014). <br />Southeastern Minnesota has experienced three 1000-year floods in the past decade: in September 2004, <br />August 2007 and September 2010 (Meador, 2013). The 2004 flood occurred when parts of south- <br />central Minnesota received over 8 inches of precipitation. Faribault and Freeborn counties received over <br />10 inches in 36 hours. The deluge led to numerous reports of stream flooding, urban flooding, mudslides