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How a unique procurement process got Ottawa's Combined Sewage Storage Tunnel underground

October 13, 2016

By Gerald Bauer

The unique procurement process for Ottawa’s Combined Sewage Storage Tunnel

It can be tough to make procurement sexy. But Gerald Bauer and his team came about as close as you can get in assisting the City of Ottawa with their unique procurement process for the City’s Combined Sewage Storage Tunnel (CSST). As the City of Ottawa celebrates the official groundbreaking for the CSST, Gerald reflects on the holistic approach taken by his team.

The City of Ottawa’s Combined Sewage Storage Tunnel is part of Canada’s Capital City’s Ottawa River Action Plan (ORAP), a collection of 17 projects to improve the overall health of the Ottawa River. The CSST is ORAP’s hallmark project and it will drastically reduce combined sewer overflows (CSOs) into the river. The project will consist of two interconnected tunnels totaling 6.2 km with a diameter of 3m, including access shaft and hydraulic structures which connect to the City’s most critical sewers.

There are many risks involved with a large tunnel project like this one. So the City and the project design team embarked on a unique procurement process and tender to address those risks and to provide the best value to the city and their contractors.

How was the process unique? While it employed a systematic review of project risks, it also solicited input from industry, stakeholders, and provincial and federal partners to develop the request for tender for this traditional design-bid-build project. The City was concerned about schedule control, cost certainty, and overall project risk mitigation. Those became our key drivers. Our design team embraced a risk management philosophy founded on allocating risk where it could best be addressed and carried it through each phase of the project.

Our intent? To produce a Procurement Process and Tender that adopted and integrated risk sharing tools that would attract quality-based contractors and allow for a fair and transparent process in selecting the best qualified contractor, within the City’s cost and schedule needs.

Based on this philosophy, we developed several goals for the process, including: 

  • Attract top-tier contractors to bid
  • Select the best contractor to complete the work
  • Emphasize continuous risk assessment and adaptation of mitigation measures
  • Make stakeholders a part of the process

A project of this scope and size presented many challenges and constraints, including complex subsurface conditions, stakeholder coordination, property and land use agreements, site constraints, and operational considerations. We took various steps to manage these challenges:

  1. Risk Register
    At the beginning of the project, we developed a detailed Risk Register and considered the numerous project components through input from tunnel industry experts, third-party reviewers, various City of Ottawa departments, and the project design team. Developing mitigation measures to best allocate and manage those risks allowed our team to continuously assess and address project risks on an ongoing basis.
  2. Risk Workshops
    At key points in the design cycle, we held risk workshops to solicit input from tunnel industry experts and others. These workshops served as value engineering or third-party reviews, as they allowed for scrutiny and an unbiased assessment of the project structure by groups not intimately familiar with the design.
  3. Subsurface Investigation
    A thorough and clearly articulated subsurface investigation program was critical to protecting both the project owner and contractor. During the preparation for the proposal, our design team partnered with a local geotechnical consultant that had extensive background knowledge of the project limits.

Our design team took many additional steps to manage the challenges of the Ottawa CSST project. You can read about these in greater detail in my complete paper, originally published by the World Tunneling Congress 2016:  Employing a Unique procurement Process for the City of Ottawa combined Sewage Storage Tunnel.

While each component of the process has been used before, what was different is how our team combined them. This holistic approach to risk mitigation is unique – in particular, obtaining contractor input during the open market period in a traditional design-bid-build process – and it’s a process that other municipalities can learn from and adapt as they embark on similar, large-scale tunneling projects.

The positive results have been clear. This procurement process has been well received in our industry – the city received 10 prequalification submissions by world class contractors, all of which included great feedback about the specific risk sharing approach to the contract. At the time of writing, the contractor prequalification process is complete. The top 5 scoring contractors/joint ventures were shortlisted and received request for tender package in December 2015. Construction of the Ottawa CSST kicked off at a ground breaking ceremony on October 11, 2016. The project is scheduled for completion in 2020.

  • Gerald Bauer

    Gerald specializes in municipal infrastructure, from planning through to the end of construction

    Contact Gerald
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