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FLOODS AND FLASHFLOODS DEFINED Flooding is a condition where water or mud overflows onto land that is normally dry. Flooding is the most common and widespread weather-related natural disaster in the U.S. and can occur with little or no warning. Active alluvial fans, like the one at Neff’s Canyon, lack a single defined flow path and are prone to sudden, fast, and unpredictable floods, called flash floods. Flash floods most often occur following intense rainfall when excessive water from creeks and rivers fills dry creeks and river beds. DETERMINING FLOOD RISK To identify a community’s flood risk, the Federal Emergency Management Agency (FEMA) conducts and manages a Flood Insurance Study. These studies include data for water flow rate and flow velocity, as well as surveys of rainfall and area topography. Flood Insurance Studies are then used to create flood hazard maps that outline a community’s flood risk areas. INSURANCE IMPLICATIONS OF FLOOD RISK FOR NEFF’S CANYON FEMA creates Flood Insurance Rate Maps (FIRMs), which show varying levels of risk. Preliminary (draft) flood maps for the Neff’s Creek area, which will be part of the larger Jordan Watershed study, are anticipated to be released in Summer of 2019. These maps will designate the following flood risk areas: High Risk Areas (Special Flood Hazard Area)—There is at least a one-in-four (or 26%) chance of flooding during a 30-year mortgage in these areas. Homeowners with mortgages from federally regulated or insured lenders are required to buy flood insurance to be protected from this risk. These areas are shown on flood maps as A and AO (alluvial fan hazards with water depth and velocity shown) zones. Moderate- to Low-Risk Areas (Non-Special Flood Hazard Area)—Flood risk in these areas is lower but still exists. Homeowners in these areas are not federally required to buy flood insurance, but it is highly recommended. These areas are shown on flood maps as X (or shaded X) zones. FLOOD RISK REVISIONS AND FLOOD MAPPING CHANGES Flood risk can, and does, change over time. Flood risk can change for many reasons, including land development, erosion, increasing storm intensity, wildfires, and other causes. As a result, FEMA is using the newest technologies to update flood maps across the country. The new maps will help residents in the vicinity of Neff’s Creek better understand their flood risk so they can take steps to protect their community and their homes. Once effective, the new maps will be used for community floodplain management and flood insurance rating purposes. An Introduction to Flood Risk FOR NEFF’S CREEK & MILLCREEK CITY SPRING 2019 ---PAGE BREAK--- Jupiter Dr Oakview Dr Parkview Dr Fortuna Way Adonis Dr Ruth Dr Ceres Dr Wasatch Blvd Mount Olympus Way Hale Dr Brockbank Dr Gary Rd Diana Way Apollo Dr Viewcrest Dr Lares Way Achilles Dr Lois Ln Hermes Dr Mathews Way Eastcliff Dr Evelyn Dr Abinadi Rd Zarahemla Dr Neptune Dr Barbara Way Roger Dr Eastoaks Dr Spruce Dr Oak Rim Way Covecrest Dr Powers Cir Brockbank Way Loren Von Dr Park Terrace Dr Mars Way Foubert Ave Sunset View Dr Spruce Cir Park Hill Dr Pin Oak St White Way Cove Point Dr Crest Oak Dr Mulholland St E 3820 S Olympus View Dr S Parkview Dr Wasatch Dr Aurora Cir Pluto Way E 3900 S St Cliff Dr Lares Cir Parkview Cir Juno Cir Eastcliff Cir Fortuna Cir Hagoth Cir Helaman Cir Adonis Cir Hermes Cir Lois Ln Parkview Dr Hermes Dr Mars Way Adonis Dr Diana Way 215 215 A AO,2,1 AO,2,2 AO,2,2 AO,2,2 AO,2,3 AO,2,3 AO,3,3 AO,3,4 SHADED X SHADED X SHADED X SHADED X SHADED X SHADED X SHADED X Neffs Creek Flood Hazard Study Limit of Study Effective Floodplain Revised Floodplains Zone,Depth,Velocity A AO, 2, 1 AO, 2, 2 AO, 2, 3 AO, 3, 3 AO, 3, 4 SHADED X 0 500 1,000 250 Feetµ www.jefuller.com