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  • Flood Control District's work allows 240 structures to be removed from FEMA flood maps

    Feb 21, 2020 | Read More News
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    The Pima County Regional Flood Control District recently completed a floodplain mapping study that removed 240 westside structures and more than 700 acres from the Federal Emergency Management Agency (FEMA) Special Flood Hazard Area (SFHA), which carries a designation as having high risk of flooding. 

    FEMA has approved the study, which will officially change the Flood Insurance Rate Map (FIRM) for the area and become effective on May 27, 2020. 

    A SFHA designation requires homeowners in the floodplain to carry often costly flood insurance. Once the new FIRMs become effective in May, homeowners shown to be outside the floodplain will no longer be required under federal regulations to purchase flood insurance for mortgaged structures.

    The Red Butte area, south of Ajo Way near Camino de Oeste, was first mapped by FEMA in 1989. The District correctly recognized that improved mapping accuracy through the use of better data and modern floodplain mapping techniques available today could likely reduce the size of the FEMA floodplain.

    The new mapping techniques allowed the District to model flood flows through a two-dimensional grid system of approximately 750,000 nodes, each representing 20 square feet of terrain. The new techniques model floodplains more accurately in areas like the Red Butte area than what was possible 30 years ago.

    The new maps will also reduce or eliminate the regulatory burden and added cost of floodplain development for property owners when they wish to construct new improvements on their property.