sentences:  In particular, within unincorporated Solano County approximately downstream and upstream of Willow Avenue are a designated 100-year floodplain.For incorporated Vacaville areas, along Horse Creek approximately downstream of Leisure Town Road and approximately upstream of the sewer maintenance area are designated within the 100-year floodplain.For the Middle Branch Horse Creek, 100-year flood designations were made immediately upstream of Interstate 80 and approximately upstream of Interstate 505.