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

A title search was conducted by the County as part of the acquisition process to determine the limits of the
sovereign state lands (SSL) versus private ownership. The hammock areas are above mean high tide elevations
and were part of the County acquisition of Hidden Harbour. The 50-60 acres of marsh habitat and 20-30 acres of
tidal creek and bay area buffered by the hammocks are sovereign lands. These sovereign wetland areas will
receive secondary ecological benefits by the proposed enhancement activities but are not quantified for
mitigation credit under the proposed plan. Enhancement of these hammocks will be conducted by herbicide
application of the B. pepper, which in some areas are particularly large trees (refer to photos). Due to the
environmental damage that cutting and removing the snags would cause, the B. pepper will be allowed to decay
in place and no construction activities are proposed within the system. This will allow the natural recruitment and
generation of appropriate hydrophytic vegetation, while opening areas for easier wildlife access to forage and
nest. An intensive initial effort to eradicate the B. pepper will be conducted, followed by annual maintenance for a
minimum of five years. As with all the habitat creation and enhancement areas for the property, the quantity and
schedule of maintenance events will be evaluated to ensure continued success with emphasis on eradication
with as minimal coverage of exotics as possible.
There is additional acreage of coastal hammock habitat along the north bank of the Manatee River and within the
western portion of Hidden Harbour. This acreage may be included within the mitigation plan at a later date. This
linear zone along the river was purposely removed from inclusion to evaluate how this habitat may provide any
necessary buffers and/or mitigation associated with the County school facilities, as well the relationship with the
proposed Upper Manatee River Road and associated stormwater and floodplain compensation facilities
constructed on the Hidden Harbour property.
Marsh Enhancement (ME 1 – 1.8 acres) – aerials indicate the marsh was historically impacted by clearing of
the adjacent upland area (to be restored by Manatee County) and the installation of a free-flowing surficial well
that will be appropriately grouted and capped. The dominant marsh vegetation includes chalky bluestem
(Andropogon glomeratus), dog fennel (Eupatorium capillifolium), with additional coverage provided by
maidencane (Panicum hemitomon), low panicums, and scattered primrose willow (Ludwigia repens). The
proposed enhancement of this system includes herbicide eradication of the fennel and willow; with a dense
planting of wax myrtle along the perimeter to provide buffer cover. An existing wet access road crossing is
located near the southern extent where the marsh connects to the adjacent forested wetland hammock. This road
will be vacated and hydrophytic vegetation will be allowed to regenerate in this area.
Non-FDOT Mitigation Habitat Improvements –
Upland Habitat Restoration (Estimated 40-50 Acres) & Marsh Creation (Estimated 4-6 Acres) As noted,
these additional habitat improvements were previously proposed to provide FDOT mitigation credits, and will still
be conducted to some degree by Manatee County to provide mitigation for anticipated wetland impacts
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