Oshawa Wharf Condition Assessment
LOCATION: Oshawa, Ontario
CLIENT: Hamilton-Oshawa Port Authority (HOPA)
TIMELINE: 2023
KEY PERSONNEL: Nick MacEachern
Project Description
Harbourside Engineering Consultants was retained by the Hamilton-Oshawa Port Authority (HOPA) to complete a visual inspection program to aid their board in assessing several wharf structures within the Port of Oshawa. The Port of Oshawa, located in the City of Oshawa on the north shore of Lake Ontario, consists of east and west wharves, both of which regularly accept cargo ships. A standalone pier is located on the west side of the turning basin, which is open to the public from the adjacent Lakeview Park and is currently used to support light loadings, and not intended for commercial purposes.
Harbourside’s Scope of Work
As per the client’s requirements, Harbourside Engineering was required to undertake inspections, structural assessments, determine the residual life of the existing structures and generate proposed recommended repairs / rehabilitation of several wharf structures.
The visual component of the inspection included topside visual and diving inspections. In general, the condition of the underwater portions of structures were observed as fair to good, with some typical corrosion on all observable steel surfaces. This was deemed reasonable for the age of the steel structures in a freshwater environment. In general, indications of substantial deterioration and deformations was not observed by Harbourside Engineering or their sub-consultants during inspections. It was however, observed at the north end of the west wharf, that the sheet pile was leaning out significantly at the top compared to the rest of the structure. This lean indicated that some movement of the tie anchorage had likely occurred at those locations. Harbourside Engineering Consultants recommended limiting loading within those areas until more significant upgrades were possible.
Structural elements exposed above the waterline, such as concrete caps and curtain walls, were generally observed to be in fair condition, though more severe deterioration. Broken concrete (likely due to suspected impact loadings), spalls, and exposed deterioration of reinforcing steel were observed in several locations.
The analysis yielded limited surcharge ratings, with Harbourside Engineering recommending that existing usage and operations should only continue as their current level as established in recent years. Increasing operations was not advised. This is notable for older structures for which the design parameters were not fully understood in the absence of necessary documentation and more advanced field studies. Harbourside Engineering provided an inspection scope and frequency recommendation for continued monitoring beyond the current scope of work.
Unique Elements
Given that the analysis was completed with limited information regarding the design, construction, and maintenance of the majority of existing structures, Harbourside also recommended that additional investigations could be completed to further assess existing structural properties and geotechnical conditions. These investigations would help minimize potentially conservative assumptions. Cost estimates for proposed minor maintenance and durability rehabilitation work for each structure were developed and provided to the client.
At a later date, Harbourside was awarded the contract to complete detailed design and drawings for the proposed minor repairs for the existing wharf structures.
Noteworthy Project Experience
Project management, planning and inspection of a marine facility consisting of multiple construction types.
Inspection included NDT and structural analysis.
Development of comprehensive report outlining existing conditions for the facility.
Analysis of existing ties sheet pile, timber crib and suspended reinforcing concrete slab wharf structures using inspection results, available information and inferred geotechnical parameters.
Development of recommendations proposed for minor rehabilitation of existing structures to prolong useful service life – later awarded to HEC in a separate contract