Project Summary - Woodside Ferry Terminal Pontoon Replacement

Project Name: Woodside Ferry Terminal Pontoon Replacement, Dartmouth, Nova Scotia
Project Owner: Halifax Regional municipality
Completion Date: December 2014
Contract Value: $3,298,600.00 CAD

 

Project Description:

Waterworks Construction was awarded a contract to design-build  the Woodside Ferry Terminal pontoon replacement.  Waterworks engaged local consultants PINTO Engineering help to develop the best value design for project. The approach was second to none; every aspect of the requirements was analyzed and scrutinized to ensure the most innovative strategy with respect to construction methodologies available, installation procedure, lifespan of the pontoon, schedule, project cost, maintenance requirements, and overall buoyancy including draft & freeboard.

The pontoon was constructed using high performance concrete (HPC) based on the latest bridge code requirements for durability.  KIM® is an innovative admixture product that was included in the concrete mix design.  The product generates millions of microscopic crystals as cracks develop in the concrete to create a self-healing, impermeable structure.  Furthermore, the product is used in potable water structures and does not impose any environmental challenges to fish habitat.  High stress areas of the pontoon were post-tensioned concrete to further enhance durability.

The hull was completely filled with expanded polystyrene foam, which virtually eliminates water ingress and provides ultimate flotation reliability.

Hot dipped galvanized reinforcing steel was used throughout the concrete structure.  Additionally, the structural steel components with marine exposure (fender connection system, dolphin guide arms, berthing wing ends) were hot dipped galvanized.  Marine coatings have limited service life and were not considered for use on any steel elements.

Serviceability and longevity were primary considerations during the design process; the structural steel elements and other features inherent to the design were developed with this in mind.  The pontoon will never need to be dry-docked, and when steel components reach their design life they can be replaced or serviced with absolutely no disruption to regular ferry operation.

 

Firm’s Responsibility on the Project:

Once the final design was approved, pontoon construction began.  A brief description of Waterworks’ scope is itemized in the following list:

  • Construct a massive temporary slipway at Waterworks’ marine terminal.
  • Form and pour concrete pontoon barge on the slipway.
  • Fabricate, galvanize, and install all steel components.
  • Extrude and install rubber fender system.
  • Fabricate electrical systems including weatherproof wall packs, lighting, and power outlets.
  • Fabricate and install a new pontoon deckhouse, complete with metal membrane roof, windows, and garage doors.
  • Launch the complete pontoon on pneumatic ship-launching airbags, then temporarily support the existing ramp and swap the existing pontoon with the replacement (without disrupting transit operations).

While the construction process was underway Waterworks hosted regularly scheduled meetings with HRM & Transit authorities, as well as all relevant stakeholders to ensure every aspect of the construction process complied with the specifications and the best interests of HRM.

Launching the 1,000 Tonne pontoon with airbag technology was the most exciting part of the project.  This unique blend of archaic and modern methodology is uncommon in North America.  A short video of the pontoon launch is embedded below:

 

Relevance of the Project:

  • The effort to propose, design, build, and install the replacement pontoon cells highlights Waterworks’ ability to work with a team of designers to develop the best-value solution for a challenging project.
  • This project exemplifies Waterworks' years of experience in the heavy civil construction industry.  This experience has been gained from numerous unique and challenging projects like the Woodside Ferry terminal Pontoon Replacement.
  • The project utilized a large labour force, with many construction operations occurring simultaneously.  In order to mitigate hazards a safety plan was developed for the project and hazard assessments were completed.