Chapter 3 - St. Marks and Wakulla Rivers Greenway

What is a Floodway?

The floodway is defined as the area where the river leaves its banks during a flood with the floodwaters having movement in the same direction as the river.

Riparian Greenways provide the opportunity for linking the benefits of preserving the floodway while maintaining or improving river water quality and facilitating economic development through ecotourism. The many acres of public lands in St. Marks River watershed, including the Wakulla River, provide outstanding recreational opportunities to complement those associated with the greenway. By conserving the natural green corridors along the rivers, receation and scenic qualities will continue to flourish in the future.

The greenway vision for the St. Marks and Wakulla rivers watershed is based upon the compilation of the land use land cover data, the Florida Game And Freshwater Fish Commission critical habitat data, existing land ownership patterns, and the recreation and cultural and historic data. The St. Marks and Wakulla Rivers Watershed Greenway map (Figure 1) results from taking the Game and Fish's critical habitat data and overlaying it with the existing land use and land cover using the GIS system. The map reflects the natural greenway corridor along the rivers (see Figure 1 Watershed Greenways).

An assessment of natural resources within the watershed was completed In order to identify the potential greenways. The objective of this assessment was to identify environmentally sensitive lands or lands with important habitat value. Each of the local comprehensive plans has policies which protect wetlands and other environmentally sensitive lands; however, efforts to protect such lands can be limited by the lack of information regarding the location, presence or type of resources. The District's GIS was used to compile the best available resource data from several sources including the Florida Game and Fresh Water Fish Commission (FGFWFC) and Florida Natural Areas Inventory (FNAI). Compiled information included land use and land cover; strategic habitat conservation areas; and rare animal, plant and communities occurrence data. The land use and land cover information was obtain by classifying satellite imagery using the methods described elsewhere in this report.

The rare species occurrence and wildlife habitat information were obtained from several statewide geographic data sets developed by FGFWFC which incorporated FNAI data. These data were created by the FGFWFC to identify areas in need of protection in order to maintain biodiversity. This information represents the most comprehensive and detailed effort yet undertaken for this purpose in Florida (Presley 1994). These data sets also represent the best available estimate of Florida lands requiring some form of conservation to ensure that biodiversity is maintained for future generations. The FGFWFC GIS was used to assess the degree of security provided to rare species by the current system of conservation lands and to identify important habitat areas not currently protected (Cox et al., 1994). The lands recommended by FGFWFC for additional protection are referred to as "strategic habitat conservation areas". These lands are needed to meet minimum conservation goals for 30 species of wildlife inadequately protected by the current system of:

* conservation lands,

* high quality sandhill sites,

* high quality scrub sites,

* high quality pine rocklands site,

* high quality examples of tropical hardwood hammocks,

* bat maternity caves and winter roost caves,

* wetlands important to the breeding success of eight species of wading birds, and

* lands important to the long term survival of 105 globally rare species of plants.

Another geographic data set was developed by FGFWFC containing known locations of many animals, plants, and natural communities. A set of maps referred to as "regional biodiversity hot spots" were created which included the following information:

* areas where large numbers of 52 selected species co-occur,

* areas supporting rare plant and wildlife communities,

* over 25,000 known locations of rare plants, animals and natural communities,

* county boundaries and conservation land boundaries, and

* coastal areas that support key components of biological diversity.

The hot spots resulted from investigation of species richness which located habitat for seven or more focal species (Class 3), five or six focal species (Class 2), and three or four focal species (Class 1) (McGrail et al. 1994). Class 1 lands were generally of lower natural resource quality than Class 2 or 3, including large tracts in silviculture and agriculture that are used by wide-ranging habitat generalists such as turkey and bobcat. The FGFWFC data served as a starting point for the resource assessment. In order to ensure that the identification of potential greenways included the most environmentally sensitive or significant lands, the District's GIS was used to modify the FGFWFC habitat data. The FGFWFC habitat areas are shown in Figure 10 - Natural Resource Assessment Map .

The FGFWFC strategic habitat conservation areas and biodiversity hot spots (Classes 2 and 3) were combined and overlain with the land use and land cover data. In instances where habitat data coincided with non-natural land cover (such as silviculture, agriculture or urban uses), it was omitted from the lands identified as potential greenways. The remaining habitat areas which coincide with natural land cover types, are shown on Figure 10 . This was noted in the map legend since the most obvious difference between the entire and modified habitat data is the presence or absence of silviculture lands. Wetland areas identified in the land use and land cover assessment but not identified by FGFWFC as strategic habitat or Class 2 or 3 hot spots were also considered as environmentally significant lands for potential greenways (see Figure 10).

The FGFWFC data shows that there are extensive areas of critical habitat throughout the watershed. The modified FGFWFC habitat which coincides which natural land cover includes primarily riverine corridors and wetland areas. Additional areas of modified habitat which coincide with natural uplands forest were also identified. Although these upland areas are environmentally significant, they occupy more isolated or scattered areas limiting their function as greenway linkages. The wetlands identified by the District may also contain focal species habitat (less than 5 focal species). These areas identify additional potential greenway "spurs". The proposed greenway corridor is the unifying linkages between the largest and highest quality habitat areas.

The process undertaken in this effort served to identify those areas within the St. Marks and Wakulla riverine corridors and associated wetland and habitat corridors that may be worthy of consideration as greenway linkages. The FGFWFC report could be used in a companion fashion to enhance the protection of additional strategic habitat conservation areas proximate to the proposed greenway.

The greenway corridor of hardwood swamps and bottomland forest along the St. Marks and Wakulla rivers provide wildlife habitat while functioning as conduits for many species of birds, the Florida Black Bear, and other animals. The water quality of the rivers can be maintained through the natural filtering capabilities of the hardwood swamps and bottomland forest, if a sufficiently wide greenway corridor is maintained and if Best Management Practices are followed in silviculture operations. The greenway can also function as a filter for residential stormwater runoff and septic tank nutrient rich leachates. By protecting the bottomland hardwood swamps and limiting the intensity of development in these wetlands, the impacts on the St. Marks river can be reduced. Also, by guiding development away from the river, the hazards related to flooding on property and lives is also reduced.

The Town of St. Marks is the only incorporated municipality adjacent to the greenway and is the primary hub for recreation and commerce along the two rivers. The Town of St. Marks is a commercial port with the St. Marks River supporting an electric power generation facility, barge transportation and commercial fishing operations. The conservation of the St. Marks and Wakulla Rivers Greenway may provide the local Chambers of Commerce with a marketing tool for ecotourist-related businesses. The Governor-appointed Florida Greenways Commission is working to establish a statewide network of greenways linking communities and natural areas. Wakulla County is perfectly positioned for creating greenways linking the Apalachicola National Forest, the St. Marks National Wildlife Refuge, Wakulla Springs State Park and the Tallahassee to St. Marks State Historic Rail Trail. There is a tremendous potential for marketing this watershed and the surrounding region as an ecotourism destination because of the variety of opportunities available. The resource areas of the region and watershed combine to provide the critical mass of opportunities necessary to entice visitors to the communities in the watershed and in particular Wakulla County. The greenway can provide the framework to tie the watershed's resource areas together and provide a unifying theme for future partnerships.

The St. Marks and Wakulla rivers abound in history. Visitors along the Tallahassee -St. Marks Historic State Rail Trail often know very little about the history of the lands which they are riding through. Through the development of historical trails on the rivers and along the rail trail, the St. Marks and Wakulla Rivers Greenway could provide visitors another recreation outlet based on the history of past cultures and events. A significant historical interpretation site currently exist at Fort San Marcos de Apalachee and the Natural Bridge Battlefield site on the St. Marks River.

Analysis of the land ownership data collect from the property appraisers offices of Jefferson, Leon and Wakulla counties indicates that much of the land within one mile of the rivers are in large, single ownerships . This information is important for determining which greenway development strategies may be appropriate for particular river segments. The following discussion on the proposed St. Marks and Wakulla Rivers Greenway provides a description of each river by river segments.

The River Swamp Section

Much of the upper portion of the St. Marks River north of Natural Bridge is owned and managed for silviculture by the St. Joseph Land and Development Corporation. A few areas in the extreme northern reaches of the watershed near Interstate 10 and around Natural Bridge have multiple owners and are used for agriculture, silviculture and residences. Much of the surrounding land is classified as hydric swamps or wetlands, and is considered important habitat by the Florida Game and Freshwater Fish Commission (see Figure 10 - Resource Assessment). This section of the greenway also filters stormwater run-off, serves as a buffer area for natural flooding, provides a sediment sink from erosion of adjacent agricultural lands, and the wetlands here provide nutrients to the river ecosystem. The upper reach does not provide good opportunities for canoeing because much of the river is not navigable due to dense wetland vegetation and the fact that are few public access points along the upper reach.

Although all the previous mentioned attributes of the St. Marks and Wakulla rivers will benefit from greenways, the greatest benefit of creating a greenway along this portion of the river may be protection of the water quality of the entire watershed. Land development of all kinds has a disproportionate influence on downstream areas. In this area the river has less flow and is narrower, the upland disturbances tend to occur closer to the St. Marks River's smaller tributaries. Consequently, nutrient and sediment loads tend to be higher per acre along these smaller streams than downstream where the river becomes larger (Binford and Buchenau 1993). Proper stormwater management is therefore critical for this section. The ditches and swales that drain into the river function as conduits for sediments and nutrients. An effective stormwater management system can make the difference in river water quality.

The Natural Bridge Section

Between Natural Bridge to the Town of St. Marks, the river's ownership patterns become more fragmented. The riverfront is lined with homes along the west bank for about 2.5 miles below Natural Bridge. There are few scattered homes on the west side of the river south of Newport. Much of the land in between on the west bank appears to be in two ownerships and is managed for silviculture. The entire east bank of the river from Natural Bridge to St. Marks National Wildlife Refuge has only a few ownerships and is also managed for silviculture.

The Natural Bridge Section of the greenway functions as a filter and a conduit. Based on the land use and land cover and critical areas maps, the middle section of the greenway along the St. Marks River has the greatest potential for filtering or buffering the adjacent silviculture operations as well as the residential development located between Natural Bridge and Newport. There are few areas in this section with excellent habitat. The river swamps are relatively narrow and much of the adjacent uplands are pine plantations. This portion of the greenway provides opportunities for canoeing and boating. It also provides a natural corridor for animals to move between the Refuge and the swamps and uplands of the upper portion of the watershed.

Newport to St. Marks Section

South from Newport, the greenway is influenced by increasing urban development along the west bank in juxtaposition with the St. Marks National Wildlife Refuge on the east bank (see Figure 6). This section of the St. Marks River is deeper and wider due to channel dredging by the US Army Corps of Engineers for oil carrying barges. The barges serve the oil tank farms and the City of Tallahassee Power plant located along the rivers western bank in the town of St. Marks.

Much of the ecological benefits afforded by the greenway will accrue on the east side of the river which is bordered by the Aucilla Wildlife Management Area and the St. Marks National Wildlife Refuge. Much of the greenway corridor is intact along the west bank between Newport and the industrial complex at St. Marks, future residential development in the area could ,however, degrade the greenway's ability to function as a natural filter, if stormwater runoff, noise, extensive land clearing, and visual intrusions are not managed properly (see Figures 6,and 10).

The land along the Wakulla River is more fragmented by roads and residential development than it is along the St. Marks River (refer to Figure 5). The following discussion describes the three Wakulla River sections of the greenway - Wakulla Springs, Between the Bridges, and Lower Bridge to Apalachee Bay. Silviculture is the predominate use of the western bank. South of the US 98 Bridge the land is managed for silviculture and as a safety zone for Olin Corporation. The river flows through the St. Marks National Wildlife Refuge to the west and south of the port Town of St. Marks where it joins with the St. Marks River.

Wakulla Springs Section

The Wakulla Springs section of the greenway is delineated by the Wakulla Springs State Park above State Road 365 (see Figure 5 and Figure 7). The Wakulla Springs section provides habitat for animals, sources of native seeds for the river system, filters upland stormwater runoff and the surrounding swamps and functions as a sediment and nutrient sinks. The Wakulla Springs section provides visitors a place to swim, hike, tour on the spring fed river and view wildlife.

Between the Bridges Section - State Road 365 To U.S. 98

There are many homes on both banks of this section of the river. Homeowners have generally done a good job protecting vegetation on their properties and along the banks, but habitat along this portion has never the less been degraded by development. Canoeing, kayaking, and fishing are frequent activities in this section of the greenway, with many users accessing the river at the State Road 365 and U.S. Highway 98 bridges. The "Between the Bridges"section of the greenway functions primarily as a filter, but the corridor also likely provides a conduit for animals moving between the Wildlife Refuge, Wakulla Springs State Park, and the Apalachicola National Forest. Occasionally, visitors can see manatees feeding in the river's shallows.

Lower Bridge to Apalachee Bay Section

This section of the greenway starts below the US Highway 98 bridge and extends to Apalachee Bay. The west bank of the Wakulla River below the US 98 bridge is within the St. Marks National Wildlife Refuge. Much of the greenway on the west bank functions as habitat and a conduit where animals can move from the surrounding uplands to the river and to the Gulf of Mexico. Olin Manufacturing has maintained a forested buffer for their industrial plant operations along the east bank of the Wakulla River. This buffer follows the east bank from just south of the US 98 Bridge to the Shell Island Fish Camp in St. Marks. Olin's property along the river functions as habitat, a filter for stormwater and noise, and a conduit for animal movement. Olin has developed a small park on the water for the use of its employees.