FCD has recently begun a new floodplain delineation study of the Lower Gila River between Miller Road and Bullard Avenue in cooperation with the Cities of Buckeye and Goodyear. The new study uses updated topographic mapping and a recently approved FEMA model (HEC-RAS 2D). The model will evaluate the spillover from the river to the north into the Lower Gila River Overflow Area (previously referred to as the Buckeye Slough which is located between Apache and Perryville Roads on the north side of the river). This new modeling will provide more accurate floodplain delineation potentially decreasing floodplain limits and flood depths. There may be, however, some areas where the flood depths could increase.
The Lower Gila River floodplain downstream of the Overflow Area, between the Hassayampa River and Miller Road, is also being evaluated using recent topographic mapping. This area will be included in the delineation if there are meaningful changes to the floodplain limits or depths.