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https://hdl.handle.net/11681/45901| Title: | Environmental Assessment and Finding of No Significant Impact : Additional Offshore Borrow Areas - St. Johns County, Florida, Shore Protection Project and St. Johns County, Florida, Coastal Storm Risk Management Project (South Ponte Vedra Beach and Vilano Beach Reaches) |
| Authors: | United States. Army. Corps of Engineers. Jacksonville District. |
| Keywords: | Shore protection Flood control Environmental management Beach erosion Beach nourishment Saint Johns County (Fla.) |
| Publisher: | United States. Army. Corps of Engineers. Jacksonville District. |
| Abstract: | The St. Johns County Shore Protection Project (SJC SPP) and St. Johns County Coastal Storm Risk Management (SJC CSRM) authorized projects provide coastal storm risk management to shoreline development, environmental habitat, and infrastructure at risk from beach erosion along SJC (Table 1 and Table 2). Historical storm damages and ongoing erosion have contributed to shoreline storm barrier loss and destabilization. Over the past decade the SJC beaches have been severely impacted by coastal storms (most notably Hurricanes Matthew, Irma, and Dorian). The recent storm damages resulted in 2019 Federal Emergency Management Agency (FEMA) EA for emergency beach berm and dune restoration activities along the SJC coastline (SJC 2020). The existing sand borrow source for the SJC SPP and SJC CSRM has historically been the St. Augustine Inlet and Ebb Shoal Complex. After the recent (2021) completion of the initial construction of the SJC CSRM project, post construction surveys indicate that there is currently a total volume of between 200,000 and 400,000 cy available sand within the St. Augustine Inlet Complex borrow areas. However, it is not expected that this quantity of sand could be efficiently removed given that it exists as a very thin layer of beach compatible material. The St. Augustine Inlet Ebb Shoal is currently estimated to contain approximately 1.6 to 1.8 mcy of beach compatible sand. More material is required for future nourishment of the SJC CSRM (Vilano Beach), SJC SPP (St. Augustine Beach), potential emergency projects, and conceivable future authorized projects in SJC. Both the SJC CSRM and SJC SPP are subject to placement regulations set out by the Inlet Management Plan (IMP) which establishes strategies to best manage sediment in the inlet and sand bypassing activities for placement of beach quality sand on adjacent eroding beaches of inlets or passes. The St. Augustine IMP calls for one third of the sediment removed from the inlet to be placed on the shoreline to the north and the remaining two thirds to be placed on the shoreline to the south. The IMP limits the available quantity of sand that could be dredged for either project at any given time, which may limit the ability of the Corps to build the construction template. The continued use of the St. Augustine Inlet as the primary/only sand source in SJC for the SJC SPP and SJC CSRM projects is unsustainable. Therefore, new borrow sources for beach quality sand are needed for the SJC CSRM and the SJC SPP projects. |
| Description: | Environmental Assessment and Finding of No Significant Impact |
| Rights: | Approved for Public Release; Distribution is Unlimited |
| URI: | https://hdl.handle.net/11681/45901 |
| Size: | 337 pages / 53.1 MB |
| Types of Materials: | PDF/A |
| Appears in Collections: | Environmental Documents |
Files in This Item:
| File | Description | Size | Format | |
|---|---|---|---|---|
| EA and FONSI - Additional Offshore Borrow Areas – St Johns County, FL 2022.pdf | 53.1 MB | Adobe PDF |  View/Open |