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

REGIONAL MITIGATION PLAN
BACKGROUND INFORMATION
Mitigation Project: Serenova Preserve – Sites 2, 3, 4, 8 Project Number: SW 74
County: Pasco
Location: Sec. 23, R17E, T26S, Sec. 34, R17E, T25S
IMPACT INFORMATION
DOT FM: 2563161, SR 52 – Hicks to Moon Lake
ERP #: 4007804.005 COE #: 90IPI-03363
Drainage Basin: Upper Coastal Water Body(s): Buckhorn Creek SWIM water body? N
MITIGATION ENVIRONMENTAL INFORMATION
Mitigation Type: Restoration and enhancement
Mitigation Area: 26 acres
SWIM project? N Aquatic Plant Control project? N Exotic Plant Control Project? N
Mitigation Bank? N Drainage Basin: Upper Coastal Water Body(s): Pithlachascotee River
SWIM water body? N
Project Description
A. Overall project goal: The Serenova Preserve and adjacent Starkey Wilderness Preserve (total over 20,000
acres) is owned and managed by the SWFWMD (Figure A). After extensive evaluation and ranking of wetland
restoration and enhancement opportunities within the Serenova Tract, four separate project sites (2,3,4,8) were
determined could provide the most important wetland hydrologic improvements within the property. Three
projects involve culvert installations and removal of berm material associated with the Pithlachascotee River and
Five Mile Creek (Figure B). The Pithlachascotee River has two access road berm crossings (Site 2 - actively
used, Site 4 - abandoned) and Five Mile Creek has one crossing (Site 3). Each crossing requires improvements
to restore surface water flow conditions through the floodplains and minimize continuous problems with erosion
and sedimentation. Site 8 is a large outfall ditch of a cypress system, requiring the construction of ditch blocks in
order to restore wetland hydrologic functions.
B. Brief description of pre-construction condition: The Pithlachascotee River and Five Mile Creek are
forested wetland floodplains of relatively high-quality with a diverse canopy cover dominated by laurel oak, sweet
gum, cypress, red maple, cabbage palm, and tupelo. A sub-canopy has saplings of the same species as well as
Virginia willow, buttonbush, and wax myrtle. Ground cover is sparse due to canopy cover and dominated by
various fern and sedge species. However, hydraulic characteristics of the floodplains have been altered by
berms constructed prior to public acquisition, as well as undersized and insufficient culverts. The abandoned
Pithlachascotee River crossing had a 600 ft. long berm that blocked and diverted surface water flow to a dredged
river channel segment. The river channel had a partially collapsed bridge tressel that would catch debris and
block flow (Figure B, Site 4, site photos). Another 680 ft. long berm crossing of the river is utilized for
management access, but had insufficient and undersized culverts (Figure B, Site 2). The upstream contributing
flow was diverted through just three culverts in the main river channel. As a result, the wetland floodplain
upstream of the berm would have impounded surface and less water contributing to the downstream wetland
floodplain. The Five Mile Creek roadway crossing had an appropriate size culvert but insufficient rubble rip-rap to
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