Jacksonville Harbor (Mile Point) Navigation Study, Duval County, Florida
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Jacksonville Harbor (Mile Point) Navigation Study, Duval County, Florida FINAL INTEGRATED FEASIBILITY REPORT AND ENVIRONMENTAL ASSESSMENT March 2012 INTRACOASTAL WATERWAY JACKSONVILLE HARBOR St. JOHNS RIVER Navigation Study for Jacksonville Harbor (Mile Point), Final Report, Integrated Feasibility Report and Environmental Assessment, Duval County, Florida DEPARTMENT OF THE ARMY JACKSONVILLE DISTRICT CORPS OF ENGINEERS P.O. BOX 4970 JACKSONVILLE, FLORIDA 32232-0019 REPLY TO ATTENTION OF JACKSONVILLE HARBOR (MILE POINT) NAVIGATION STUDY DUVAL COUNTY, FLORIDA FINDING OF NO SIGNIFICANT IMPACT I have reviewed the Environmental Assessment (EA) for the proposed action. This Finding incorporates by reference all discussions and conclusions contained in the Environmental Assessment enclosed hereto. Based on information analyzed in the EA, reflecting pertinent information obtained from agencies having jurisdiction by law and/or special expertise, I conclude that the proposed action will not significantly impact the quality of the human environment and does not require an Environmental Impact Statement. Reasons for this conclusion are in summary: a. Per the Recommended Plan, the existing Mile Point training wall would be reconfigured in order to redirect difficult crosscurrents. This should reduce or eliminate navigation restrictions impeding the movement of deep draft vessels. Dredged material resulting from the project would be used to restore salt marsh at nearby Great Marsh Island. This beneficial use of dredged material is also the least cost disposal option. A Flow Improvement Channel is being proposed in order to restore the historical connection between Chicopit Bay and the Intracoastal Waterway and St. Johns River. Reconfiguration of the training wall would result in the loss of approximately 8.15 acres of salt marsh and approximately 0. 75 acres ofoyster habitat; however, this loss would be more than offset by the restoration of up to 53 acres of salt marsh at Great Marsh Island and approximately 2.77 acres ofoyster habitat at the island and along the reconfigured wall. b. Coordination with the US Fish and Wildlife Service and the National Marine Fisheries Service has been completed per Section 7 ofthe Endangered Species Act. c. An Environmental Resource Permit (Water Quality Certification) shall be obtained from the State of Florida, and the proposed work would be performed in compliance with Water Quality Certification conditions. A final determination of whether the project is consistent with the Florida Coastal Management Program shall be made by the State with issuance of the permit. d. A significant cultural resource is located within the project area; however, there should be no adverse effects to this resource with the current project design. Coordination with the State Historic Preservation Officer and appropriate Federally recognized tribes has been completed with no adverse effect. e. Measures to eliminate, reduce, or avoid potential impacts to environmental and cultural resources shall be implemented. ~If~( ,---;--~ b1Z.., 6./ /.JU"Lir( ~~ ,JR. Date , Corps ofEngineers Commanding 2 FINAL INTEGRATED FEASIBILITY REPORT AND ENVIRONMENTAL ASSESSMENT JACKSONVILLE MILEPOINT JACKSONVILLE, DUVAL COUNTY, FLORIDA LEAD AGENCY: Jacksonville District, U.S. Army Corps of Engineers Mile Point is located in Duval County, Florida. It consists of about 5000 feet of shoreline located along the north shore of the St. Johns River and east of the Intracoastal Waterway (IWW). The study will determine plans to evaluate the Mile Point erosion problem and to provide recommendations for reducing or relocating the difficult crosscurrents during the ebb flow at the confluence of the St. Johns River with the IWW that are interfering with safe navigation in the channel. The St. Johns Bar Pilots and the Captain of the Port, United States Coast Guard (USCG), have enacted a restriction which requires inbound vessels with a draft greater than 33 feet inbound and 36 feet outbound to be restricted to transiting close to or on a flood tide before entering the harbor to avoid the difficult ebb flow currents. The Federal objective of water and related land resources planning is to contribute to National Economic Development (NED) consistent with protecting the nation’s environment, in accordance with national environmental statutes, applicable executive orders, and other Federal planning requirements. For more information, contact Samantha Borer, U.S. Army Corps of Engineers, Planning Division, P.O. Box 4970, Jacksonville, Florida 32232-0019, phone (904) 232-1066 or facsimile (904) 232-3442. SUMMARY FINAL INTEGRATED FEASIBILITY REPORT AND ENVIRONMENTAL ASSESSMENT ON JACKSONVILLE HARBOR (MILE POINT) NAVIGATION STUDY DUVAL COUNTY, FLORIDA The Mile Point Shoreline of Jacksonville Harbor (Jax Mile Point) is located between river miles four and five west of the Atlantic Ocean along the St. Johns River. This area on the north bank of the St. Johns River has been experiencing shoreline erosion. The confluence of the St. Johns River and the Intracoastal Waterway (IWW) is within the Mile Point study area. The IWW enters the main channel of the St. Johns River at an angle of approximately 45° from the north, out of Sisters Creek (Figure 1). From the south, the IWW enters out of Pablo Creek at an angle almost parallel to the main channel flow out of Pablo Creek, with flow usually running in the opposite direction of the flow of the river. On the south bank of the St. Johns River is the Mile Point training wall, also known as the Little Jetties. The non-federal sponsor is the Jacksonville Port Authority. The purpose of the Jacksonville Mile Point study is to assess Federal interest in navigation improvements and related purposes, with particular reference to erosion of the Mile Point shoreline. An evaluation of benefits, costs, and environmental impacts determines Federal interest. The feasibility study was authorized by a resolution of the House Committee on Transportation and Infrastructure adopted March 24, 1998 for Mile Point, Florida. Need or Opportunity: The U.S. Army Corps of Engineers (USACE) has been studying the continued erosion of the Mile Point shoreline and the effects of the navigation restrictions. The following erosion and navigation problems related to the existing Mile Point area necessitated this feasibility study. There have been catastrophic failures on the north Mile Point shoreline due to erosion. Figure 2 highlights a failure event at parcel no.8856 on the Mile Point shoreline. In this particular case, the head scarp appears to have eroded 75 to 100 feet back from the seawall. Other erosion events are documented in Figure 3 and date from 1986 to 1997. Due to difficult crosscurrents at the confluence of the IWW and the St. Johns River during the ebb tide (Figure 1), the St. Johns Bar Pilots have enacted navigation restrictions for inbound vessels with a transit draft greater than 33 feet to avoid transiting during the ebb tide. Due to the angle of entry of the flow at the confluence, there is a danger that large vessels could turn in response to the current and leave the channel resulting in groundings or collisions. i FIGURE 1: CROSSCURRENTS PRODUCED BY PERPENDICULAR INTERSECTION OF THE IWW WITH THE ST. JOHNS RIVER AT PABLO CREEK FIGURE 2: POST-EROSION EVENT ON THE NORTH SHORELINE DEC 1990 ii FIGURE 3: EROSION EVENTS DOCUMENTED ON MILE POINT NORTH SHORELINE. 1997 1992 1986 1994 1990 Major Findings and Conclusions: The proposed actions of this report are in the national interest and can be constructed while protecting the environment from unacceptable impacts. Benefits of the proposed action would minimize the impacts of the flows out of the IWW during the ebb tide, slow or redirect the velocities away from the north bank, and slow the progression of erosion. Reducing or redirecting the difficult crosscurrents in the harbor would allow the pilots to reduce or eliminate navigation restrictions impeding the free movement of vessels. As is detailed in the Engineering Appendix (Appendix A) on page A-4, numerical modeling results indicate that the potentially dangerous crosscurrents exiting the IWW southern channel under ebb tide can be redirected to more closely parallel the alignment of the Federal navigation channel instead of being focused toward the erosion prone areas along the northern shoreline of Mile Point. Adverse impacts from the project, that would be mitigated, would include loss of salt marsh adjacent to the existing Mile Point training wall. Measures were taken to avoid, minimize, and compensate for adverse impacts. The restoration of Great Marsh Island is the least cost dredging alternative. It provides beneficial use of dredged material through the creation of habitat beyond the required mitigation. The creation of a flow improvement measure is proposed to prevent any adverse impacts on water quality within Chicopit Bay from restoring Great Marsh Island. iii Alternatives: Alternatives that were evaluated include a number of non-structural and structural alternatives. Non-structural alternatives include: x Operational measures such as light-loading, use of tide, additional tugs x No action alternative Structural alternatives include: x North shoreline groin field x San Pablo Creek IWW submerged weir x Rebuilding of Mile Point Training Wall to original dimensions x 150-foot training wall reach channel widening of the channel x Eastern Chicopit Bay diversion channel x Relocating (Reconfiguration) Mile Point Training Wall x