The original Provincial Trunk Highway 59 and Provincial Trunk Highway 101 (PTH 59N/PTH 101) interchange was designed in the mid-1990s. With the increase in traffic volume, operational and safety issues arose over time. In 2014, Manitoba Infrastructure initiated design-build construction of the full interchange, which included an active transportation crossing of PTH 101 and upgrades to the intersection of PTH 59/PR 202. WSP Canada was awarded the role of Owner’s Engineer by Manitoba Infrastructure in May 2014, and completed the functional design, prepared procurement documents, and provided oversight during construction.
The project was divided into two phases - phase 1: functional design and development of procurement documents for a design-build contract and phase 2: engineering construction oversight.
Phase 1: Functional design
WSP provided engineering services for the functional design of a full interchange at the junction of PTH 59N and PTH 101, as well as other related works. This included the following engineering components:
- A “system” interchange at PTH 59N and PTH 101 (i.e., there will be no traffic signal controlled intersections);
- Realignment of PTH 101 near the interchange;
- An active transportation grade separation along the Raleigh/Gateway corridor across PTH 101;
- An upgraded intersection at PTH 59N and PR 202 with signalization and channelization;
- Preparation of conceptual plans for a future diamond interchange at PTH 59N and PR 202;
- Potential realignment of Wenzel Road with a new east-west component tying into PTH 59N at the intersection with PR 202;
- Provision for future six lanes on PTH 101 and for six lanes on PTH 59N;
- Paving of certain service roads leading to the PTH 59N and PR 202 intersection;
- Closure of seven service road connections to PTH 101 and PTH 59N; and
- Closure of Knowles Avenue at Lagimodiere Boulevard, with construction of an easterly extension of Headmaster Row connecting to a new north-south road providing access to Knowles Avenue.
WSP’s role during this phase was to develop a functional design report and assist with the development of specifications and tender documents to procure a design-build Contractor.
Phase 2: Construction oversight
Once the contract was awarded, WSP needed to provide the following construction oversight:
- Providing resident services as a third level of quality oversight to ensure the design-build contractor conformed to project specifications; and
- Primary point of contact between the design-build contractor and Manitoba Infrastructure.
WSP managed the review of several thousand submittals from the design-build contractor.
Overseeing the design and construction of the largest interchange the province has ever constructed, without interrupting the highest volume of traffic on a seasonal basis was a highly complex assignment. WSP, along with Manitoba Infrastructure, created an 850-page specification document with the technical requirements for the project. The project specifications dealt only with the known conditions at the time of tendering. Unknown conditions led to contract change orders, which added complexity to the work.
The project team numbered well over 80 personnel in 15 different disciplines.
WSP had to address many challenges throughout the development of the functional design and procurement documents. Key challenges included:
- Completing the functional design and request for pre-qualifications on a tight deadline ahead of the construction date;
- Proposing five alternative interchange configurations that met current and future traffic capacities, and updating traffic forecasts and analysis;
- Minimizing the amount of land that needed to be acquired outside of the Manitoba Infrastructure right-of-way;
- Determining what properties needed to be expropriated;
- Geotechnical investigation and soil testing, and environmental assessment of privately owned properties could not occur until after property acquisition was completed; and
- Developing a public engagement program to provide information and obtain public feedback. This required an extensive stakeholder management plan.
During phase 2, construction oversight of the project, WSP faced additional challenges:
- Ensuring that the proper lines of communication were followed;
- Managing an electronic document control system of over 31,000 documents;
- Staffing the site with WSP personnel to ensure that quality was not compromised during off hours;
- Conducting an environmental assessment when contaminated material was discovered on one of the expropriated properties.
Opportunities to innovate
The PTH 59/101 project utilized 15 disciplines or departments within WSP and/or sub-consultants. The scope of application of the engineering disciplines is very broad. For instance, during the functional design, WSP considered a total of five alternative designs for the Interchange and recommended one alternative to Manitoba Infrastructure, which formed the basis of the design for the design-build contractor.
There were multiple opportunities to innovate during the design and construction of the interchange. These innovations include: the use of wick drains, the creation of haul roads for embankment fill to alleviate congestion on PTH 101 and PTH 59 during construction, the use of specialized machinery such as rock trucks and silt fence installation attachments to expedite the construction schedule, and the use of shear keys in sensitive geotechnical areas.
An architect was included on the WSP team to design architectural relief on the bridge piers, abutments and barriers throughout the project. This aesthetic treatment added a unique layer of interest.
As the largest interchange project undertaken by Manitoba Infrastructure and WSP in Manitoba, WSP staff had the opportunity to work on not only a signature project, but also the frost active transportation/emergency vehicle “throughpass”, built in Manitoba. Challenges included: the geometric design, addressing current drainage areas in the study area, and developing a traffic plan that needed to change on a regular basis to meet the needs of the contractor and the travelling public.
Social / Economic / Environmental impact
The Functional Design Report had to consider and develop mitigation strategies for the social, economic and environmental impacts of the project.
To mitigate social impacts, Manitoba Infrastructure and WSP held stakeholder engagements within the neighboring communities and agencies.
In terms of economic impact, the removal of the signals at the PTH 59/101 intersections alleviates the need to stop at the intersection and allows traffic to travel smoothly through the interchange, resulting in time and fuel savings, as well as the added advantage of reducing greenhouse gas emissions.
Identification and mitigation of environmental impacts was accomplished by completing Environmental Site Assessments (ESA) on all properties affected by the interchange footprint during the functional design phase and completing phase 2 ESAs on any potentially contaminated properties.
Management and meeting owner’s needs
For phase 1, the budget was developed through the proposal and sub-consultant agreement process. For phase 2, the budget was developed on a time and materials basis with an estimated budget to completion. This approach proved to be economical and cost-effective for Manitoba Infrastructure.
WSP created a project management plan to ensure all aspects of project management were adhered to throughout the project. This included a quality management plan, a risk management plan and a communications plan.
Quality and risk management principles were applied in a meaningful way by working together with the many levels of Manitoba Infrastructure and FCCL to ensure quality standards were followed and any unknown risks were dealt with in a timely manner. This allowed for rapid resolution of issues.