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

C. Brief description of conducted work: Construction was conducted in 2003 and 2004, commencing with exotic
species eradication, followed by earthwork grading to remove the spoil and some upland soil material to create tidal pool
& creeks, saltmarsh, and an ephemeral freshwater marsh (Figure C, 2004 aerial). The salt-marsh enhancement was
conducted through decreasing some grade material and using the two constructed tidal pool & creek systems to
increase hydrologic connections and flow to the marsh habitat (Figure D, 2008 post-construction & current conditions
aerial). Some of the removed spoil and open field was restored to upland flatwood habitat, with supplemental planting
conducted to enhance the remnant oak hammock along the east side of the project. Native tree, shrub and herb species
were planted in the upland and wetland habitats, followed by routine herbicide treatments to aid in maintaining the
habitat conditions. Additional details on the construction, planting, and current conditions provided in Attachment A.
Aerials and site photographs depict the pre-post habitat conditions.
D. Brief explanation of how this work serves to offset the impacts of the specified DOT project(s): The majority
of the wetland impacts designated for mitigation at the Tappan Tract were associated with low quality ditches, with the
remaining wetland impacts mitigated at Cockroach Bay (SW 56 - Freshwater and SW 75 - Saltwater sites) and Apollo
Beach (SW 67). The mangrove enhancement (0.77 ac.) compensates for the 0.3 acre of mangrove impact. Additional
mangrove generation has naturally occurred within the enhanced and constructed salt marsh. For the 3.5 acres of
saltwater ditch impacts, the mitigation includes salt salt-marsh creation (1.19 ac.), salt-marsh enhancement (3.06 ac.),
tidal pool creation (0.41ac.), saltern enhancement (0.53 ac.), and tidal pool enhancement (0.72 ac.). For the 0.6 acre of
freshwater ditch impacts, the mitigation includes freshwater marsh creation (0.55 ac.) and hardwood hammock
enhancement (1.20 acres). Considering 94% of the wetland impacts were associated with ditches, the mitigation is
considered appropriate to compensate for these low quality wetland impacts.
E. Brief explanation of why a mitigation bank was/was not chosen, in whole or in part, including a discussion of
cost: The only mitigation bank in the Tampa Bay Drainage Basin is the Tampa Bay Mitigation Bank (TBMB), which was
not permitted at the time mitigation selection had to be designated for this FDOT project.
F. Brief explanation of why a SWIM project was/was not chosen as mitigation, in whole or in part, including a
discussion of cost, if the anticipated impacts are located within a SWIM water body: This is a SWIM – sponsored
habitat improvement project conducted on property owned and managed by the City of Tampa.
MITIGATION PROJECT IMPLEMENTATION
Entity responsible for construction: SWFWMD Operations Department, planting by private contractor
Entity responsible for monitoring and maintenance: Private consultant on contract to the SWFWMD
Proposed timeframe for implementation: Commence: Design, 2000, Construction, 2003-2004 Complete:
Quarterly herbicide treatments and semi-annual monitoring through 2009, followed by perpetual maintenance as
necessary by City of Tampa. Additional details provided by SWFWMD-SWIM Section, City of Tampa Parks, FDOT
Mitigation Program Manager.
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