Four Corner - Texas Water Development Board

y the USFWS and TPWD indicate that threatened and endangered species of plants and
animals are not considered to be a concern within the confines of the study area.
F. Extent Of Flood Plain In Area - As part of this investigation, the Federal
Emergency Management Agency (FEMA) National Flood Insurance Program Flood
Insurance Rate Maps (FIRMs) were evaluated for the study area. The FIRM panel 120 of
550, map number 48157C0120-H, dated September 30, 1992, and map number
48157C0120-J, dated January 3, 1997, were reviewed for this project.
The northeastern-most comer of the study area boundary crosses the well defined
channel of Keegans Bayou at two locations. Keegans Bayou is designated as a "Zone
AE" area which consists of a special flood hazard area potentially inundated by a 100-
year flood. The 100-year flood is contained within the channel of Keegans Bayou in this
area according to the FIRMs reviewed during this investigation. Zone AE specifically
refers to areas of the 100-year flood in which base flood elevations have been
determined.
The southwestern-most corner of the study area ts encompassed by a flood zone
associated with Red Gully, based on the FIRMs reviewed for this area. Red Gully
generally flows southeast and south within the boundaries of the study area and then
flows south/southeast into Oyster Creek. Oyster Creek flows into the Brazos River
which then flows into the Gulf of Mexico.
The area surrounding Red Gully is designated as a Zone AE. This area which consists of
a special flood hazard area that has a potential to be inundated by a 100-year flood;
floodway areas in Zone AE are also designated on the FIRMs. The Red Gully 100-year
flood zone is not contained within the channel similar to the well defined channel of
Keegans Bayou.
Additionally, a Zone X area is also located in the southwestern-most corner of the study
area. Zone X areas are defined as areas below the 500-year flood elevation and areas
within the I 00-year flood area with average depths of less than one foot or with drainage
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Preliminary Engineerng Report