Waterfront and Coastal Structures Knowledge Area  

Updated: 03-20-2017

 

INTRODUCTION

Waterfront structures serve as the transition point between seagoing vessels and the infrastructure that supports them while they are in port. Once attached to power, waste collection and other utilities support the waterfront becomes a vibrant and dynamic city extension to the existing installation. Coastal structures include navigation, dry docks, fleet moorings, seawalls, groins, jetties, and breakwaters that are all designed to ensure the safe and efficient operation of the land ocean interface. Components include bulkheads, pilings, structural framing, decks, utility trenches, dolphins, and fender systems. Similar CPC challenges exist for large civil works structures such as dams, spillways, and other flood protection structures, especially if they are close to the coastal environment. Because the waterfront interface is at the extreme level for corrosion, a thorough understanding of that environment and the associated stresses placed on waterfront and coastal structures is vitally important to ensure mission support, safety, readiness and prevention of environmental contamination.

DESCRIPTION

Awareness of the issues that are associated with CPC for waterfront and coastal facilities and structures such as piers and wharves and the supporting components that comprise the structures require many engineering disciplines such as structural, electrical, environmental, mechanical, civil, and specialty engineering areas such as cathodic protection and paints and coatings expertise. Each discipline has an essential role to play in ensuring that the waterfront infrastructure is designed, constructed and sustained.

Photo of waterfront facilities and docks

Photo credit: MC 1st Class Christopher B. Stoltz / U.S. Navy via Reuters file

The Waterfront Environment

Understanding the waterfront environment and its risks and stresses on facilities is an absolute must for engineers, architects and sustainment engineers. Salt water is an excellent electrolyte contributing to an aggressive corrosive environment. Hydrostatic forces, wind, salt spray, currents, tides, waves, and ice all contribute to corrosion and erosion of waterfront systems and structures. Waterfront operations and industrial activities (pollution, fuels, hazardous materials, deicing salts, and stray currents) often add to the corrosion severity.

Photo of waterfront facilities and docks

 

Waterfront Zones

An atmospheric zone is any portion of the waterfront structure above the splash zone Splash Zone is the portion of the structure just above the tidal zone. This portion of the structure is predominantly dry, but is likely to intermittently wet by wave action and wind driven spray. In UFGS 03 31 29 Marine Concrete the splash zone is defined as:

  • 2 meters above the tidal zone for locations protected by seawalls or sheltered from open-ocean waves;
  • 6 meters above the tidal zone for unprotected locations; tidal Zone is defined as the portion of the structure that is located between Mean Lower Low Water (MLLW) and Mean Higher High Water (MHHW);
  • In areas with minimal tides, this would be defined as the area located between Mean Sea Level (MSL) and Mean High Water (MHW);
  • Submerged Zone the submerged portion of the structure that is located below Mean Lower Low Water (MLLW); and
  • In areas with minimal tides, it would be defined as that portion of the element below Mean Sea Level (MSL).
Graphic of the waterfront zones

Waterfront and Coastal Zone Protective Techniques

Methods of Corrosion Control in the Waterfront and Coastal Zone include:

Through understanding the severity and stresses associated with the waterfront environment and the associated waterfront zones, the design, construction and sustainment of new and existing facilities will have a greater possibility of meeting mission requirements over the life cycle. It is essential that the right materials are selected, installed and maintained. The waterfront is a high stress area for utility systems, pipelines, steel structures, concrete and reinforcing steel, and timber. New materials that are corrosion resistant such as fiber reinforced plastics (FRP), UHMW and HDPE are now in use. In short, where and when to use this enormous combination of materials to create a viable and productive fabric of facilities in the waterfront and coastal zone requires skill, coordination and knowledge. The engineer, architect and sustainment professional should seek assistance of SMEs in this area to ensure that their projects will survive in this dynamic zone. (See also the: Waterfront and Coastal Zone Training Vignette).

Consulting Technical Discipline Subject Matter Experts (SME) associated with the Waterfront Environment

The Waterfront and Coastal Discipline Area SMEs provide invaluable consultation skills developed from years of experience assessing corrosion prevention requirements and many environments. The SMEs can translate local conditions into the interdisciplinary solutions that provide immediate and long-term benefits to the installation and its SRM bottom line costs. Typical consulting services provided by the SMEs include:

  • Multi-discipline coordination and understanding
  • Materials analysis and selection
  • Problem assessment
  • Failure analysis
  • Environmental Severity impacts
  • System and material selection
  • Review and assessment of contractor deliverables
  • Quality assurance
  • System design
  • SRM analysis and recommendations (system inspection and testing assistance)
  • Hazards analysis
  • Assessment of new technologies
  • Process analysis
  • Anti-terrorism threat analysis and protection technologies

Relevant Codes and Standards

Department of Defense

Unified Facilities Criteria (UFC)

Unified Facilities Guide Specifications (UFGS)

U.S. Army Corps of Engineers - Public Works Technical Bulletin (PWTB)

National Association of Corrosion Engineers (NACE) and Society for Protective Coatings (SSPC)

  • SP0169, Corrosion Control of External Corrosion on Underground or Submerged Metallic Piping Systems
  • SP0285, Corrosion Control of Underground Storage Tanks By Cathodic Protection
  • SP0388, Impressed Current Cathodic Protection of Internal Submerged Surfaces of Steel Water Storage Tanks
  • RP0193, External Cathodic Protection of On-Grade Metallic Storage Tank Bottoms
  • SP0196, Galvanic Anode Cathodic Protection of Internal Submerged Surfaces of Steel Water Storage Tanks
  • Steel Structures Painting Council (SSPC) Paint No. 16

National Electrical Manufacturers Association (NEMA)

  • ANSI /NEMA C57.12.29

ASTM International

  • ASTM A242
  • ASTM A588
  • ASTM A606 (Thin sheets)
  • ASTM A690 (H-Piles and Sheet Piling)
  • ASTM A709 (Bridges)

ADDITIONAL RESOURCES

Organizations