SOW_Cape_Ferry_Dock_8_pages_.pdf

STATEMENT OF WORK

FOR

CAPE LOOKOUT NATIONAL SEASHORE

HARKERS ISLAND, NC

Project Title

Repair of Main Ferry Dock at Cape Lookout, South Core Banks

Prepared by

Cape Lookout National Seashore

Jeff West

PMIS: 201696F

1.0 – BACKGROUND

A new dock was built in 2020 and since construction, NPS has identified multiple issues including extensive concrete cracking, damages to the aluminum landing/ramp structure, and several locations of damage to the steel pipe guide piles coating system. By November of 2021, the park had documented separation of pods and additional cracking of the modular pods. By February of 2022, the pods were visibly flexing, and large chunks of concrete were cracked.

In October of 2022, an inspection was conducted. The objective is to provide an independent structural evaluation of the floating dock. They made numerous observations and did an in-depth investigation of the structure. In short, they concluded:

• This wave loading is significantly below the design requirement indicated in the floating dock specification and based on the observed float actions, it is plausible that wave actions are a major contributor to the structural failures observed.

• Construction phase photos show the floats being assembled on land and there is observable sagging and misalignment of the assembled floats.

• Based on the approximate ¼” wide gap observed at the broken longitudinal aluminum angles inside the troughs, thermal stresses may have partially contributed to the failure of these angles. The assembly of the sections on land in direct sunlight followed by the transfer of the assembly into the cooler waters present during April could have caused the angles to significantly contract relative to the concrete and thereby incur locked-in stress due to anchor restraints.

• The intended splice at the waler joints has failed at each splice location and the longitudinal angles are broken in multiple locations due to tension failure. With no continuous longitudinal tension members in the top of the floating dock, the tension stresses in the top of the dock are transferred to the 2” thick concrete slab at the locations where the walers and angles are discontinuous. These locations are the locations where the majority of the concrete cracking has occurred, which would be expected due to the low tensile strength of concrete.

• The structural damage observed in the floating dock is widespread and is likely progressing. There were no observed indicators that the damages resulted from berthing actions. In our opinion, based on observations, it is more likely the observed discontinuities in lateral and longitudinal ties, in combination with wave action, and potential locked-in stresses from assembly are more prevalently

• The winter storm of December 24, 2023 that hit CALO with 50+ MPH winds, caused such severe damage that the dock is currently unusable. It was closed due to safety concerns. Currently, the ferry dock remains closed to all uses due to significant safety concerns.

2.0 – SCOPE

Contractor will remove the modular floating dock and will be responsible for its disposal. To facilitate the removal, the 70’ gangway pilings will be extended to support a cross piece capable of lifting the gangway clear of the floating dock; height should be sufficient to insure it is not struck by the dock or railings at High tide plus

3’. The floating modular dock will be replaced by painted steel barges that will be connected and serve as a floating dock and facilitate the ADA ramp and ferry passenger’s egress. All barges will be connected so they float as one unit (see Concept Drawing). The contractor will provide all materials, equipment, personnel, and vessels.

3.0 - OBJECTIVES - GENERAL REQUIREMENTS

-Barges should function as a floating dock.

-ADA ramp shall be modified to the barges and present a consistent height for ferry boat access.

-The 70’ aluminum gangway lift will be left in place and painted to match the existing pilings it is built on.

-At least 8 dock cleats will be installed, 4 sound side, and 4 shore side.

-NPS owned Black poly foam pods and safety equipment will be reinstalled in a configuration that best supports the ferry boat operation.

-Clean and dispose of all debris.

4.0 - TASK AND DESIGN PERFORMANCE REQUIREMENTS:

• The aluminum ADA ramps will be removed by the contractor to the NPS Harkers Island Marina for repair and rebuilding to fit the new barge heights relative to the ferry boats for proper egress from and to ferry boats.

• The NPS owned Black poly foam pods and chain will be removed by the contractor and stored for reuse at the conclusion of the project.

• NPS rescue ladders and life rings will be removed and reinstalled on the barges.

• The Landing section Pilings will have 4’ of steel tubing added to them, and a cross piece welded into place that will support the weight of the 70’ Aluminum Gangway. This structure will be painted with epoxy paint that approximates the same color as the existing steel pilings and left in place for future repairs and operations.

• The 70’ aluminum gangway extending from the fixed portion of the dock to the ramp landing will be raised utilizing the new structure and a chain hoist to facilitate the removal and replacement of the floating sections.

• The approximately 60’x20’ main modular floating section, and the 20’x14’ ramp landing modular floating dock will be removed/demolished.

• One new 10’x40’ new steel barge will be placed in center line with the fixed dock and ramp.

• Four new 10’x20’ steel barges will be placed symmetrically on either side of the larger bard (2 to each side) providing a 20’x50’ floating dock and extension for the aluminum gang way (see concept drawing).

• The gangway will be adjusted to center upon the extended landing portion of the barge.

• Contractor may utilize spud barges, and/or utilize existing pilings for stabilization, but the dock should function as a floating dock, rising and falling with the tide.

• Contractor will provide all required equipment, materials, and personnel.

5.0 DELIVERY:

-Contractor can deliver materials prior to start of job to the harbor area at Cape Lookout National Seashore.

131 Charles Street, Harkers Island, NC, 28531.

-Contractor can also load vessels and operate out of this harbor for the duration of the project. Contractor’s vessels cannot impede the current operations of the harbor for park or concession vessels.

-Contractor must be present for all deliveries. CALO is not responsible for any materials or equipment delivered.

6.0 USE OF GOVERNMENT FURNISHED PROPERTY:

Contractor is expected to reuse the 70’ gangway, the modified ADA ramp, NPS ladders and rescue ring, and

NPS owned Black poly foam pods and chain.

Contractor will provide all other necessary tools, equipment and materials.

7.0 REMOVAL AND RECYING OF BUILDING MATERIALS:

A. Contractor will provide a secured/lockable on-site dumpster for removal of trash and other rubbish that can be located at the NPS Harkers Island Marina.

8.0 SECURITY/ SAFETY:

Contractor will provide a safety plan to the contracting officer before the start of work any on-site work. A safety plan will include job standards and requirements providing a complete analysis of job procedures and the requirement of the work activity. A Job hazard analysis will be reviewed daily.

Include in your safety plan phone numbers and directions to local emergency medical facilities including local emergency medical technicians.

All accidents must be reported immediately to the Contracting Officer.

9.0 PLACE OF PERFORMANCE:

-Work will be performed at the ferry dock on South Core Banks. Red Dot on attached map. Latitude

34°37'21.81"N, Longitude 76°31'31.60"W .This area is only accessible by boat or barge, there is no vehicle access and no bridge.

10.0 PERIOD OF PERFORMANCE:

30 days.

11.0 SUBMITTALS REQUIRED:

a. Barge layout engineered drawing

CONCEPT DRAWING

Current Dock Layout

END OF SECTION