Public Notice
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DEPARTMENT OF THE ARMY JACKSONVILLE DISTRICT CORPS OF ENGINEERS 4400 PGA BOULEVARD, SUITE 500 PALM BEACH GARDENS, FL 33410 REPLY TO ATTENTION OF August 1, 2018 Regulatory Division South Permits Branch Palm Beach Gardens Permits Section PUBLIC NOTICE Permit Application Number SAJ-1993-01955(MOD-PWB) TO WHOM IT MAY CONCERN: The Jacksonville District of the U.S. Army Corps of Engineers (Corps) has received an application for a Department of the Army permit pursuant to Section 404 of the Clean Water Act (33 U.S.C. §1344) and Section 10 of the Rivers and Harbors Act of 1899 (33 U.S.C. §403) as described below: APPLICANT: Hillsboro Inlet Improvement & Maintenance District Attention: Mr. Jack Holland 2861 NE 22nd Court Pompano Beach, Florida 33062 WATERWAY AND LOCATION: The maintenance dredging is located within Hillsboro Inlet, the entrance channel to the inlet, and the beach fill sites which are located south of the inlet along the north section of Pompano Beach approximately 100 feet north of Department of Environmental Protection monument R-25 to approximately 500 feet south of R-25, and along the U.S. Coast Guard’s shoreline on the north side of the Inlet along the south section of Hillsboro Beach in Broward County (Section 29, Township 48 South, Range 43 East), Atlantic Ocean. Directions to the site are as follows: From Southbound I-95 take exit 38A East Copans Road; continue east to U.S. 1, turn South onto U.S.1 and continue to NE14th Street, turn east onto NE 14th Street and continue to State Road A1A (North Ocean Drive), turn north onto A1A and continue to the Hillsboro Inlet Bridge, cross the bridge and take the right and follow the road to the lighthouse. The project is in open water within the inlet. APPROXIMATE CENTRAL COORDINATES: Latitude: 26.25826° Longitude: -80.08128° PROJECT PURPOSE: Basic: The basic project purpose is to perform maintenance dredging and sand by passing activities that include placement of material for shoreline stabilization. Overall: The overall project purpose is to conduct maintenance dredging, sand bypassing activities at the Hillsboro Inlet on the north side of the Inlet along the south section of Hillsboro Beach, and south of the Inlet along the north section of Pompano Beach. EXISTING CONDITIONS: The project site is at the Hillsboro Inlet which connects the Intracoastal Waterway to the Atlantic Ocean. The existing area surrounding the project consists of beach sand, sea oats, sea grapes, residential and commercial buildings, and State Road A1A. A detailed aquatic resource analysis was conducted in August of 2004 indicated seagrass was not present within the proposed dredge/fill areas. Seagrasses were observed in Hillsboro Bay, west of the navigational channel (i.e. secondary interior dredge area). The seagrass bed in this area is dominated by Halophila decipiens intermixed with areas of Halophila johnsonii, Halodule wrightii and Thalassia testudinum. The bed edges were identified approximately 145 to 190 feet from the center of the channel. Currently the inlet is dredged to a depth of -20 feet National Geodetic Vertical Datum (NGVD). The dredged beach-compatible sand is by passed through the existing Hillsboro Inlet dredge (HID) discharge pipeline and placed along the shoreline of the Inlet. The submerged pipeline is constructed of non-floating rubber and is stationary along a trench at the bottom of the inlet. The line is partially buried with sand and is not subject to movement. Offshore of Hillsboro along the southern shoreline the benthic habitat consist mostly of unconsolidated sandy sediment Coral reef and colonized hard-bottom is located over 600 linear feet offshore. PROJECT HISTORY: The Army Corps of Engineers re-authorized an existing Department of the Army permit on May 22, 2012. A modification was issued on July 31, 2015, which included additional work activities and removed specific requirements of the existing special conditions in the permit. Another modification was issued on September 22, 2015, to increase the area and depths for maintenance dredging of the Hillsboro Inlet and to bypass the dredged beach-compatible sand along the shoreline of the Inlet. In order to remain consistent with the expiration of the U.S. Fish and Wildlife Service (FWS) incidental take statement and to coincide with the Florida Department of Environmental Protection’s (FDEP) permit expiration date, this permit will expire September 1, 2018. PROPOSED WORK: The applicant is requesting a 10-year time extension to the existing permit (SAJ-1993-01995 issued on May 22, 2012) with the modifications to expire on September 1, 2028. The project is to maintenance dredge 18.58 acres of the Hillsboro Inlet to design depths and bypass the dredged, beach-compatible sand (125,000 cubic yards) along the shoreline (1.46 acres) of the Inlet. The exterior entrance channel to Hillsboro Inlet will be dredged to the design depth of -20 feet NGVD. The interior, sand impounding area immediately adjacent to the weir section of the north jetty will be dredged to -12 feet NGVD. The primary interior dredge area dredged to a depth of -12 feet NGVD. The maintenance dredging of the area adjacent to the secondary interior dredge area and north of the primary interior dredge area dredged to a depth of -12 feet NGVD. Additional dredging within the inlet will occur as needed to a depth of -12 feet NGVD. 2 The sand by-passing element of the project will be accomplished through the annual placement of approximately 125,000 cubic yards of sand (2.87 acres) along the shoreline from approximately 100 feet north of FDEP monument R-25 to approximately 150 linear feet south of R-26 and along the shoreline adjacent to the Coast Guard beach (1.46 acres) approximately three times per year. The existing Hillsboro Inlet dredge (HID) discharge pipeline will be used for sand placement. The pipeline will remain in place during all dredging operations, and the dredging operator will add floating line as needed to connect to the submerged line that crosses the inlet. The HID dredge is an 8-inch, hydraulic, cutter-head dredge. The cutter-head serves to loosen the material and mix it with water to create the slurry that is pumped through the discharge line. Based on equipment restrictions, it is necessary for the HID to dredge on a continuous basis, as needed, throughout the year. Dredge capacity is approximately 300 cubic yards per hour. The HID dredge does not have the capacity to reach the -20 feet NGVD design depth of the fan-shaped entrance to the Inlet (exterior dredge area). The HID may hire a contractor or purchase a new dredge with a larger capacity to dredge the entrance to design depth at a future date. Until this time, the area will be maintained to a depth of approximately -12 feet NGVD. AVOIDANCE AND MINIMIZATION INFORMATION: The applicant has provided the following information in support of efforts to avoid and/or minimize impacts to the aquatic environment: Maintenance dredging activities have been ongoing continuously since 1957, when the District was created, and are a very successful component of the overall beach management strategy in Broward County and no adverse effects to the ecosystem have occurred as a result of the bypassing operation to date. Coastal Systems conducted a pre-construction survey of the hard-bottom adjacent to the entire Exterior Dredge Area on May 9 and May 10, 2012 and a post construction survey of the area where dredging occurred in July 2012. The corresponding report documents that no hard-bottom impacts occurred as a result of dredging activities. Dredging operators are careful to ensure the equipment does not come into contact with hard-bottom to protect the environment and avoid costly down time and repairs, no hard-bottom impacts have occurred or are likely to occur in the future. Turbidity monitoring indicates that turbidity readings immediately adjacent to the dredging area range from 0.01 to 2.94 NTU’s and adjacent to the discharge area are 0.01 to 11.14 NTUs. COMPENSATORY MITIGATION: The applicant has offered the following compensatory mitigation plan to offset unavoidable functional loss to the aquatic environment: The applicant states that impacts to hard-bottom of submerged aquatic vegetation is not proposed or anticipated therefore no compensatory mitigation is required. CULTURAL RESOURCES: The Corps is aware of historic property/properties within or in close proximity of the permit area. The Corps has previously initiated and completed 3 consultation (DHR Project File No. 2013-00785), with the State Historic Preservation Office and those federally recognized tribes with concerns in Florida and the Permit Area, and the Advisory Council on Historic Preservation as applicable pursuant to 33 CFR 325, Appendix C and Section 106 of the National Historic Preservation Act. ENDANGERED SPECIES: The U.S. Army Corps of Engineers (Corps) has determined the proposed project may affect but is not likely to adversely affect the threatened and endangered swimming sea turtles; loggerhead (Caretta caretta), green (Chelonia mydas), leatherback (Dermochelys coriacea), hawksbill (Eretmochelys imbricata), Kemp's Ridley (Lepidochelys kempii), and the Loggerhead breeding critical habitat (Unit LOGG-N-19), the threatened Smalltooth sawfish (Pristis pectinata), and Johnson’s seagrass (Halophila johnsonii) and would not adversely modify any of the above listed species designated critical habitat. The Corps consulted with National Marine Fisheries Service for the project including all modifications and received concurrence with this determination pursuant to Section 7 of the Endangered Species Act by a separate letter dated December 11, 2014. The Corps will not conduct further consultation with NMFS for the project. The Corps has determined the project may affect, but is not likely to adversely affect the threatened West Indian manatee (Trichechus manatus), or its designated critical habitat.