2012 FDOT Mitigation Plan - Southwest Florida Water Management ...

Project Site 4 – This remnant tram road had a dilapidated bridge and considering there was already accessibility
over the Pithlachascottee River at Site 2, neither replacing the bridge nor placing culverts within the access berm
were necessary. Similar to the other two floodplain crossings, flow conditions were detained upstream and more
concentrated within the main channel, resulting in impounding some water upstream and minimize the spread of
water into the downstream floodplain areas. In order to restore normal floodplain flow patterns, the entire berm
material was graded in late 2007 and early 2008 to backfill the adjacent ditches. The earthwork area was
stabilized by seeding a mix of winter rye and bahia. Natural recruitment and generation of hydrophytic herbs
dominated by soft rush and sedge species occurred during subsequent years. Tree saplings (dominated by red
maple) have recruited and generated from the adjacent seed source, and gradually the canopy gap will be
restored to forested cover. Direct wetland enhancement was estimated at 11 acres (length 700 feet x width 700
feet = 11 acres). Wetland restoration from within the footprint of the berm and adjacent ditches is one acre.
TOTAL – 12 Acres
Project Site 8 – This is a large outfall ditch, with a bottom width over ranging 15-30 ft, and top-of-bank width
varying 30-50 ft. The ditch depth from top-of-bank varies because most of the ditch was dredged through
elevated topography to provide positive hydraulic gradient flow, however some portion of the ditch was over five
foot deep. But because of the excessively drained, sandy soil conditions, the ditch hydroperiods are intermittent.
Even though the cypress wetland is large, the area of direct wetland enhancement was estimated near the
northern extent of the system. The construction included three ponds dredged from within the ditch and the
resulting fill material was used to construct two large ditch blocks. By constructing the ponds and blocks from
within the footprint of the previous ditch, the construction was able to avoid disturbing any of the palmetto habitat
bordering the ditch. These blocks have halted the dewatering, and the ponds provide a water source for wildlife
during the dry season. Direct wetland enhancement was estimated at 2 acres (length 300 feet x width 350 length
= 2 acres). TOTAL – 2 acres.
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