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HomeMy WebLinkAbout20110023_Meeting Minutes_20081113Merger Team Packet 10/27/08 North Carolina Department of Transportation NEPA/Section 404 Merger Meeting Concurrence Point 2A: Bridging Decisions and Alignment Review and Concurrence Point 4A: Avoidance and Minimization November 13, 2008 NC 12 Replacement of Herbert C. Bonner Bridge (Bridge No. 11) over Oregon Inlet Federal-Aid Project No. BRS-2358(15) WBS No 32635 TIP Project No. B-2500 Dare County Merger Team Packet 10/27/08 NEPA/Section 404 Merger Meeting - November 13, 2008 NC 12 Replacement of Herbert C Bonner Bridge (Bridge No 11) over Oregon Inlet AGENDA I Introduction II Bridging Decisions and Alignment III Impacts of Phased Approach/Rodanthe Bridge Alternative (Phase I) IV Avoidance and Minimization A Phase I Construction B Bonner Bridge Demolition V Project Schedule Merger Team Packet 10/27/08 NEPA/Section 404 Merger Meeting Concurrence Point 2A Bridging Decisions and Alignment Review and Concurrence Point 4A Avoidance and Minimization November 13, 2008 NC 12 Replacement of Herbert C Bonner Bridge (Bridge No 11) over Oregon Inlet Federal-Aid Project No BRS-2358(15) WBS No 32635 TIP Project No B-2500 1. Introduction The NCDOT proposes to replace the Herbert C Bonner Bridge across Oregon Inlet in Dare County Bonner Bridge, built across Oregon Inlet in 1962, is approaching the end of its reasonable service life Bonner Bridge is part of NC 12 and provides the only highway connection between Hatteras Island and Bodie Island The replacement structure would serve the same function The Parallel Bridge Corridor with Phased Approach/Rodanthe Bridge Alternative (Figure 1) has been identified as the Least Environmentally Damaging Practicable Alternative (LEDPA) This project is identified in the 2009 to 2015 State Transportation Improvement Program (TIP) as TIP Project No B-2500 The purpose of this meeting is to review the proposed Bridging Decisions and Alignment (Concurrence Point 2A) and the proposed Avoidance and Minimization efforts (Concurrence Point 4A) for Phase I (Oregon Inlet bridge) of the LEDPA II. Bridging Decisions and Alignment The representative alignment of the Oregon Inlet bridge is contained within a 1000-foot study corridor, for the majority of its length, the bridge is centered within the study corridor The alignment of the bridge on Bodie Island was selected in order to avoid impacts to the Oregon Inlet Marina and Fishing Center parking lot, as well as the minimize disturbance to the entrances of both the Marina and the Oregon Inlet Campground The alignment was also selected to nummize impacts to wetlands and submerged aquatic vegetation (SAV) on the western side of the island The bndge alignment on Bodie Island and within much of Oregon Inlet could be altered by the design-build contractor, if the contractor can establish that its proposed alignment further mmmmmzes impacts The alignment of the bridge on Hatteras Island, however, is restricted to the current 100-foot easement that NCDOT has for maintaining NC 12 All bridge construction and traffic maintenance must remain within this easement Therefore, any shifts made during the final design of the bridge will still remain within the easement During the Constructabmlmty Workshop in 2006, the expert panel on Geotechnmcal, Hydraulics, and Coastal Engineering identified a potential threat from sound side erosion along Davis Slough NCDOT has since monitored the area of potential vulnerability and deems it prudent to extend the south terminus of Phase I an additional 2,000 feet, contingent on the availability of funds This extension is shown in Figure 2 As with the rest of the LEDPA, the bridge would remain within the existing 100-foot easement Extending the length of Phase I does not reflect a change Merger Team Packet 10/27/08 in the overall design of the LEDPA, only that a portion of Phase II is going to be incorporated into Phase I III. Impacts of Phased Approach/Rodanthe Bridge Alternative (Phase I construction) Tables 1 and 2 show the construction impacts to Oregon Inlet and to SAV and wetlands in the Phase I project area, respectively The locations of the wetland and SAV impacts are shown in Figure 2 The SAV is located just west of Bodie Island The impacts shown in Tables 1 and 2 reflect those of the representative alignment that was used for analysis in the Final Environmental Impact Assessment (FEIS) The final impacts to Oregon Inlet, wetlands, and SAV, both temporary and permanent, will be determined during final design and included in the permit applications behind Bodie Island) Table 2. Phase I Wetland and SAV Impacts (Permanent and Temporary) Wetland and S Vi ? acts ac Wetland ype ? WQ 've a Isolate or Hatte as Bodie Cowa atin or on- Co hguous ill and lan lan Classification Riverine emp haling orar em l p y ffic oot rint P aul Road rea aintenance A a Road Area Wetland N/A Non Contiguous 0 47 1 50 0 03 4 23 (E2EM1) Rivenne SAV (EIAB3) N/A Non- Contiguous 0 20 FAIR, 0 00 1 01 Riverine 4 Indicates area of SAV based on unpublished NOAA/DMF mapping and limited ground truthmg of imagery taken during 1985-1990 A survey conducted in September 2007 indicated that the current area of SAV coverage is similar to that reported when previous mapping was conducted (NCDOT 2007) The impact totals account for the additional 2000-foot bridge extension on Hatteras Island The impacts do not include those due to the demolition of the existing Bonner Bridge 2 Table 1. Phase I Stream (Inlet) Impacts Merger Team Packet 10/27/08 IV. Avoidance and Minimization Avoidance Avoidance was taken into account during the development of the entire LEDPA, including the alignment of Phase I, however, wetlands are so pervasive in the project area that it is impossible to completely avoid some impact Phase I of the LEDPA would avoid construction fill in emergent intertidal wetlands and the productive aquatic bottom of the Walter Slough area to the northwest Minimization A. Phase I Construction The following is a summary of measures to be incorporated into the design-build contract for Phase I that will further minimize impacts to wetlands and streams Oregon Inlet Dredging Dredging would likely be required in areas where the water depth is less than six feet in order to provide sufficient water depth to float and move loaded construction barges Dredging would be done to a depth of eight feet, which is deeper than absolutely necessary to float and move construction barges, but is needed due to the dynarmc coastal conditions that exist in the project area Dredging deeper than absolutely necessary would alleviate the need to frequently re-dredge the channel The contractor would coordinate with NCDOT, USACE, USFWS, NMFS, and NCDENR in developing its dredging technique and disposal plan that would minirruze harm to natural resources General guidelines for developing a detailed dredging plan would be prepared by the contractor and submitted to NCDOT for review and approval The following are dredged channel dimensions and locations • Maximum channel width = 120 feet, • Maximum channel depth = 8 feet, • Channel length shall be kept to the mimmum dimension deemed practicable, and • Dredging is prohibited in areas of SAV Dredge Spoil Disposal The nondiscretionary measures outlined in the Biological and Conference Opinions (submitted by / the USFWS in 2008, included in Appendix E of the FEIS) for the LEDPA related to piping V plovers specify that "all dredge spoil material excavated for construction barge access must be used to augment either existing dredge-material islands or to create new dredge-material islands for use by foraging plovers This must be accomplished as per the specifications of the North Carolina Wildlife Resources Commission " The appropriate location for disposal would be determined based on the character of the materials dredged, the availability of disposal sites, and coastal conditions near the time of construction Coordination on disposal locations will occur at Concurrence Points 4B and 4C The disposal of any excess material would be the responsibility of the contractor, who would be required contractually to handle and dispose of the material in accordance with NCDOT's Standard Specifications for Roads and Structures, permit Merger Team Packet 10/27/08 requirements, and local, state, and federal laws If needed, dredged materials could also be used in the nutigation of temporary wetland impacts to return the wetland areas to their pre-construction elevation Use of Work Bridges/ Haul Roads The contractor could use haul roads and work bridges for access to facilitate construction of the replacement bridge corridor alternatives Delivery trucks and crawler cranes would use the haul roads and/or work bridges to deliver and erect mayor bridge components such as piles, formwork, and girder segments The potential use of a haul road is anticipated only west of Bodie Island with the LEDPA The contractor would coordinate with the NCDOT, the USACE, the USFWS, ,? the NMFS, and the NCDENR in its development of a site access plan that would mminuze harm to natural resources For example, haul roads would be protubited in SAV areas Although a final approach would be developed by the contractor, it is anticipated that haul roads would consist of a main road a maximum of 65 feet (19 8 meters) wide that is aligned parallel to the new Oregon Inlet bridge alignment with pier access roads, or fingers, that are aligned perpendicular to the main road The pier access roads would be a maximum of 40 feet (12 2 meters) wide and could be at each proposed pier location within the length of the haul road The following are requirements would be used for construction and removal of haul roads • Haul road material would be approved by the permitting agencies and NCDOT and could consist of fill obtained from the inlet or sound, • Turbidity curtains or other means would be implemented to minimize disturbance of the sound bottom during placement of fill, • Haul roads would be constructed with geotextile fabric or other available mechanisms to nummize erosion, • Haul roads would be constructed to prevent leakage or seepage of liquid materials associated with construction equipment from entering adjoining waters or wetlands, • Haul roads would be removed and disposed of in accordance with NCDOT and permitting agency requirements, and • After a haul road is removed, the entire area covered by the haul road would be re-vegetated as directed by the NCDOT As a result of haul roads or dredging not being used in areas of SAV, work bridges would be needed at some locations along the construction of the new bridges in the inlet or sound Structural and geotechmcal design of the work bridge components would be in accordance with the latest edition of the NCDOT Structure Design Manual The contractor would design the work bridges for actual construction equipment live loads and would coordinate the work bridge design with the proposed bridge erection sequence A work bridge design also would comply with OSHA requirements The following are requirements for construction and removal of work bridges • Work bridges would be constructed to numnuze or prevent leakage or seepage of liquid materials associated with construction equipment from entering adjoining waters or wetlands, and , 4 Merger Team Packet 10/27/08 • Work bridges, including their foundations, would be removed and disposed of in accordance with NCDOT and permitting agency requirements Protected Species Commitments Conservation measures and reasonable and prudent measures specified for the LEDPA in the USFWS' Biological and Conference Opinions document (Appendix E of the FEIS) as well as measures included in the August 4, 2008 concurrence letter from the National Marine Fisheries Service (page A-63 of Appendix A of the FEIS) would be implemented Retention of Portion of Existing Structure/ Construction of Fishing Pier In a letter to NCDOT dated September 18, 2008, the US Army Corps of Engineers asked the NCDOT to explore the option of leaving approximately 1,200 feet of the existing Bonner Bridge adjacent to Hatteras Island in place This action would be designed to prevent Davis Slough from becoming the prevailing interior channel The USACE also proposed that if the existing bridge is not left in place, that a similar submerged sub-structure be implemented If no submerged structure was included within Davis Slough, then the USACE is concerned that the planned navigation zone would be rendered useless to vessel traffic The USACE would then require a longer navigation zone that would extend to the south end of the bridge As was mentioned in Chapter 8 of the FEIS, NCDOT received comments during the public hearings regarding the retention of fishing access on the north end of Hatteras Island NCDOT is exploring options for retaining fishing access at the southern end of the bridge Current options include using a portion of any traffic maintenance or work bridge needed by the contractor for construction, constructing a boardwalk under and around the new bridge, or leaving a portion of the existing bridge in place B. Bonner Bridge Demolition Use of Work Bridges/ Haul Roads For access to Bonner Bridge for demolition equipment, a work bridge likely would be used over wetlands on Bodie Island Use of a temporary haul road could be requested if it is demonstrated that such access would not result in permanent impacts to marsh communities because these communities do not have an underlying organic subsoil, or if the cost of constructing and dismantling a temporary work bridge is so high that it would not be practicable to employ that methodology As part of the demolition plan, the contractor would identify limits and dimensions of proposed haul roads, work bridges, and/or work barges required for bridge demolition work Wetland and SAV areas would be identified in the demolition plan Temporary work bridges could be required to span over the SAV and wetland areas, or a "top down' or overhead work method could be considered to protect SAV and wetland area V. Protect Schedule The following is the current schedule for the mayor project milestones as of October, 2008 Final Environmental Impact Statement September 2008 Record of Decision December 2008 Design/Build Let June 2009 0 12 b ?J i r O 0 111 \;rrrnnal64'ilcl/il? ? ? ? Reltr?'? 0 q iJ O 4 12 LEGEND O Pea Island National Wildlife Refuge i Ponds Approx. Potential Future Breach Location Phase I Phase II Phase III Phase IV 0 1 2KM ?RODANTHE 2 Miles I Sudie Payne Road 1 PARALLEL BRIDGE CORRIDOR WITH Figure PHASED APPROACH/RODANTHE BRIDGE ALTERNATIVE v Proposed Bridge Proposed Bridge within Wetland or Submerged Aquatic Vegetation Community JURISDICTIONAL COMMUNITY LEGEND NC Division of Marine Fisheries Submerged Aquatic Vegetation Data National Marine Fisheries Submerged Aquatic Vegetation Data ?.. Black Needlerush Brackish Marsh Man-Dominated Maritime Grassland Maritime Shrub Thicket Open Water Overwash Reed Stand Salt flat r Salt Shrub/Grasslands Smooth Cordgrass 0 0.25 0.5 0.75 KM 0 0.25 0.5 Mile I> J .p. rT. i lye O .J- ell <1 r1_1 m Yi 1 'ice- Note: Weiland communities within the project area were delineated through interpretation of July 12, 2002 color aerial photographs and field verification during May and June 2003. Data from the NMFS and the DMF were combined to create a map of submerged aquatic vegetation in the project area. Data supplied by the NMFS was pholc4terpreted from 1988 and 1990 aerial photography. The DMF data was generated from boat surveys conducted between 1995 and 2001. Figure WETLAND COMMUNITIES - PHASE I 2a 0 0.25 0.5 0.75 KM ' ,;' 0 0.25 0.5 Mile i, Rr e l I. O O ?O f1 Proposed Bridge Proposed Bridge within Wetland or Submerged Aquatic Vegetation Community JURISDICTIONAL COMMUNITY LEGEND NC Division of Marine Fisheries Submerged Aquatic Vegetation Data National Marine Fisheries Submerged Aquatic Vegetation Data Black Needlerush -'' Brackish Marsh Man-Dominated Maritime Grassland Maritime Shrub Thicket Open Water Overwash Reed Stand Salt Flat Salt Shrub/Grasslands Smooth Cordgrass 'tl t . f. t= T? S1 ? 1 j '. i Moth. i' ¦ ?.J 'v r IT Ilk .r: fir` 3i t- y k Nm: Wetland communities within the project area were delineated through interpretation of July 12, 2002 color aerial photographs and field verification during May and June 2003. Data from the NMFS and the DMF were combined to create a map of submerged aquatic vegetation in the project area. Data supplied by the NMFS was photo-interpreted from 1986 and 1990 aerial photography. The DMF data was generated from boat surveys conducted between 1995 and 2001, WETLAND COMMUNITIES - PHASE I Figure: 2b i . eLa iN v a a .,A LL ?r ?? ?j