In part two of this series, we look at the evolving concept of transit-oriented development.

Transit-oriented development (TOD) is not a new concept. The movement has inspired community builders to create more densely populated, mixed-use communities that are connected to transit while providing people with the ability to live, work, and play all within a walkable proximity.

In a recent article, I explored how the structures within TODs can be adapted and modified to better manage future pandemics. Today, I want to look at the concept of TOD and its evolution, as well as what it means to build one.

TOD: An Evolving Concept

Let us start at the beginning and explore why TODs matter and why the terminology we use to talk about them may not matter. By definition, transit-oriented developments are mixed-use, walkable communities centered on high-quality transit. The goal is to build complete and sustainable communities where citizens can connect to the services they need by walking, cycling, or using transit.

Although the adoption and implementation of TODs is still in its early days, there is already a debate about what part of the community, transit or development, should be built first, which is resulting in an evolution of terminology. Other recent terms that have arisen from the debate include density-oriented transit, equitable transit-oriented development, and transit-oriented communities.

Development-oriented transit (DOT), where the development leads and transit follows, along with TOD are the most heavily debated concepts and, are the two terms I’ll be focusing on today.

Over the last few decades, we have seen the “if you build it, they will come” predictions realized with developments that have sprouted around existing transit. We have seen, too, the redevelopment of existing sites to include new transit, as well as brand new sites plan the integration of transit and development from the onset.

Regardless of the order and contrary to the often held expectation, a TODs success is not contingent on one piece of infrastructure coming before the other, but rather the transit and development pieces integrating properly while ensuring each piece can successfully operate on its own. Therefore, when the two pieces come together, properly acknowledging their dependency on one another, the result is a better outcome.

Unfortunately, we have also seen plenty of examples where TOD’s are not properly integrated or where either transit or the development expect the other to be the sole reason for success resulting in development that has shied away from transit, leaving a buffer between the two, or where transit has completely steered away from the heart of a development, and even situations where transit is surrounded by parking lots without an established vision for future redevelopment.

These are not failures in TOD, but rather a learning opportunity for this industry to figure out how we can better attract developers, how to integrate with transit stations taking full advantage of those assets, and how to develop or redevelop a site, bringing together transit and development in a purposeful way.

TOD or DOT? Either Way, It Takes a Community

There are many stakeholders involved in building a TOD community and each has a unique role to play. But there is no doubt that collaboration amongst players drives better solutions. At Entuitive, our role as structural engineers is to help the planner, developer, transit agency, and architect behind a given community achieve a beautiful, seamlessly integrated, and structurally sound version of their vision.

TOD collaborators, including governments at all levels, and representing all types of transit, from bus rapid transit to light rail and heavy rail passenger lines, have recognized the importance of TODs as a way to realize their community transformation goals. For governments and transit agencies, TODs often help meet the needs of age-in-place goals and address other key demographic criteria.

Developers recognize that while transit is certainly an essential piece of any TOD, the success of TODs does not depend on transit alone. Transit naturally has peaks and valleys in ridership, so the success of the development cannot be solely contingent on transit access. TODs also depend on access to shops and services in the community via walkability and bike-ability. Developers are our experts in the attributes that make these projects successful.

Whether a developer is reimagining a brownfield site, creating a brand-new development built around existing transit lines or, even better, envisioning a community in partnership with the transit agency on a greenfield site, linking the infrastructure is paramount. This is where the role of the urban planner comes in. They design open spaces that are vibrant, pedestrian- and cycling-friendly, and ensure that the built form is at an appropriate pedestrian scale.

The complexity of integrating all the pieces of a TODs infrastructure seamlessly and without compromising the resulting community did not occur to me until I joined Entuitive. I met one leader after another who shared their sector expertise and project experience, such as residential towers, commercial buildings, institutional and cultural centres, affordable housing, special projects and renovations, and I realized the one thing many of these projects had in common was that they were adjacent to, directly above, or within a short walk from transit.

Having a unique vantage point within community TOD projects, Entuitive is a firm that can bring all the TOD pieces together in a truly integrated manner. We can help concepts be visualized, model pedestrian flows to show space functionality, model interfaces between the transit infrastructure and the adjoining tower or commercial centre, and we can develop constructible solutions to what might seem like insurmountable challenges, all while meeting the goals of design excellence.

We can do this because we know transit, we know development, and we know structures. We can connect the dots between the developer, the transit organization, and any other trades and elements to create functional, efficient TODs.

Using some real-life Entuitive examples, I want to help parse out the difference between TOD and DOT in the approach and share why I think the terminology is irrelevant and the end outcome is what matters.

TOD: Build Transit First and Development Will Come

It was not that long ago that East Village in Calgary’s Rivers District was an underdeveloped, parking lot-intensive, tired community. The revitalization of the Rivers District set out an ambitious plan to create a vibrant, mixed-use neighbourhood with character.

The Rivers District prior to revitalization shows an empty parking lot. Image c/o Calgary Herald found here

The proposed site, chosen as the prime location for the New Central Library, purposefully positioned east of City Hall, where it serves as a link to attract Calgarians to the East Village, may have been seen by many as challenging.

The challenge was due to the existing and busy LRT line that bisects the proposed site and occupies approximately 40% of the site area. At this location, the LRT enters a portal into a tunnel and on a radius. Constructing over a live rail line was no small undertaking. Added to this complexity was the design challenge to promote pedestrian connectivity from Stephen Avenue, that was blocked by City Hall, and that would invite pedestrians through to East Village. This permeability was key to the pedestrian experience and was a major design consideration.

Our team endeavored to build a new landmark civic building with an anticipated high level of community engagement over the existing LRT line, with minimal disruption to its operation, while meeting the design excellence this facility deserved.

This project is an example of a transit-led development because the library had to accommodate the LRT line and use the transit site as its guide to shape the building design. The placement of the library was intentional to create a destination that drew in pedestrians and that acted as an anchor to the surrounding development. The existing transit line could not be seen as a hinderance, but rather needed to be embraced by the team and physically by the building. It existed long before the revitalization plans for East Village and could have deterred the development but instead was an opportunity for integration.

Entuitive began with a site feasibility study to confirm whether it was possible to encapsulate the LRT line. We also considered how to create an artificial hill that would elevate pedestrians to the main entrance while allowing the desired pedestrian flow through to East Village. We developed concepts and preliminary models of what it might look like with an LRT line bisecting the site on a radius and accessibility from grade to the second level entrance.

Entuitive developed a typical framing grid that eliminated the need for transfers and which created the opportunity for a contiguous floor plate above the LRT line with a regular grid system that maximizes future flexibility. This formed the basis for the encapsulation – a new concrete structure that has a clear span approximately 12 meters across the pre-existing Calgary Transit Red Line tracks just north of the pre-existing CP Rail tunnel.

“It would have been easy to build a structure adjacent to the transit corridor, avoiding the existing LRT, but we overcame the site challenges through collaboration with the transit agency,” says Ian Washbrook, Lead Structural Engineer for the library. “We were also continually challenged to be creative in our solutions by the developer and guided by the architects’ vision.”

Ian also noted how our team applied the same creative thinking to subsequent projects.

“We learned a lot from this project and have been able to apply those lessons to the 9^th Avenue Platform Parkade across the street from the library. The 9^th Avenue Parkade is another structure built over top of an existing LRT tunnel,” he says. “We are working closely with the transit agency and are learning the importance of accommodating maintenance envelopes and protection zones for future-proofing repair/maintenance work. This will ensure the integrity of the existing structure is protected. We’re always open to evolving our designs to accommodate the best interest of all parties while working towards an integrated infrastructure that is seamless and seen as one.”

The New Central Library represents the first time in Calgary’s history that an active LRT line had been encased to enable an above-grade development project – an achievement that the Calgary Municipal Land Corporation refers to as “a real feat of engineering.”

East Village today is vibrant, and the addition of the New Central Library has given Calgary one of its most important and distinctive cultural institutions. Entuitive provided full structural engineering services, including the design of the new LRT tunnel structure and structural modifications to the vent shafts. We also completed a structural analysis of the existing LRT track supporting structure, including serviceability and structural integrity checks to ensure the existing structure and transit operations were not impacted by the new structure.

Now that the existing transit line has been built over and the community has been better connected to the city, we continue to build out. Entuitive continues to build this rich TOD vision for East Village in Calgary with recent work including the 9^th Avenue Parkade and the highly anticipated New Calgary Event Centre.

DOT: Development Necessitates Transit

Our work in densely populated communities in areas like Scarborough and York Region in Ontario are examples of development leading transit. Here, the communities are well-established and densely populated. The road network is congested, and the employment hubs, destinations, and urban fabric are set. In communities like this, transit is no longer a “nice to have”, it is a must-have to efficiently connect citizens to the places they need to be and to each other. The addition of transit also helps support the infilling of the community and further build out in a transit-oriented manner.

The Scarborough Subway Extension and Yonge North Subway Extension are extensions of the Toronto Transit Commission’s (TTC) existing lines to northern Scarborough and through York Region, respectively. Entuitive is part of a multi-discipline team acting on behalf of the Metrolinx/Infrastructure Ontario as the technical advisor for both these projects, preparing the reference concept designs, project specific output specifications (PSOS), and leading the early works contracts. These projects aim to extend existing transit lines further into pre-established communities, providing much needed service. The improved transit service is also initiating many new mixed-use developments immediately adjacent to the new lines where proximity to transit is a key attraction.

There is no shortage of challenges with projects where transit comes after development, including:

• Avoiding interruption to ongoing operations of the current transit system,
• Introducing major construction within existing communities,
• Integrating transit-supportive infrastructure, such as emergency exit buildings and stations within the community fabric
• Disruption to the mobility network, both temporary and permanent,
• Impacts to existing structures, including those that may be historical or of community importance,
• Protection of businesses and community operations during construction,
• Integration with pre-existing transit systems e.g. adjoining station concourse.

TOD is a key objective for both projects to achieve and catalyze new and vibrant mixed-use communities around transit. As a result, locating the stations, giving careful consideration for constructability, and taking a larger view of the project and the community the transit lines are connecting are critical.

As part of a larger team, Entuitive is helping locate stations in areas where the community masterplan would like to increase population and employment growth. These communities will benefit from the added transit and their public realm will be improved through architectural and urban design excellence.

We are taking a holistic view, considering how the above factors integrate within the structure. We’re drawing on the wide-ranging expertise of our team members and project collaborators, as well as through advanced building modeling, to create better solutions that work together.

Michael Meschino, Entuitive’s Transportation Principal and project lead for the Scarborough and North Yonge extensions, shares his thoughts on TOD with us.

“It doesn’t matter if the transit project is an entirely new line, an extension of an existing line adding brand new stations, or if just involves the modification and upgrade of an existing station within an existing development. We still must consider the surrounding built form. The solution is determined by the context-specific conditions.”

He goes on to give us an example of this thinking in action.

“For example, we are leading the modernization and upgrades on TTC’s College Station located below a major street in Toronto’s downtown core and locked in between two towers. Here, Entuitive is designing the addition of a new concourse, connections to the towers, new elevators, and new stairs. The project objectives remain the same for College Station, the Scarborough Subway Extension, and the Yonge North Subway Extension: to understand the existing surrounding structures, to protect them, to surgically weave in the new and/or expanded stations, and to minimize disruption to operations, whether that is transit operations or surrounding business and community operations.”

TOD or DOT: Integration Is What Matters

Transit-oriented developments require early assessment of a site’s potential, identifying all the opportunities and solutions that overcome challenges. Early conceptualization of the built form will help all partners to imagine the possibilities and to overcome any real or perceived challenges.

This requires us to reorient our thinking to accept that we need both transit AND development, because it doesn’t matter whether the transit or the development comes first. The end outcome of a thriving, sustainable community is what matters.

At Entuitive, we have built our portfolio of work supporting owner aspirations and helping developers and architect’s visions come to life.

We are not focused on recommending a single solution, rather, our approach is to expand on a problem and provide several solutions varying in cost, materials, and framing systems but ultimately delivering on our promise of uncompromising performance so that the full potential of TODs can be realized.

Our goal is to ensure that design and construction teams find the best solution as quickly as possible with sensitivity to the local market, project schedule, programming requirements, or architectural considerations.

Whether it’s a design challenge, a cost challenge, scheduling challenge, or an integration challenge between all the pieces of the TODs infrastructure, we are problem solvers. Our aim is to build a better world, starting with the communities in which we live and work. We can’t do this work alone, so working with our industry partners we collaborate to deliver transit-oriented development communities purposefully, integrating all pieces of the infrastructure within the urban fabric.

Fabiola MacIntyre is a Senior Associate, Transportation at Entuitive. To discuss this article or Entuitive’s transportation services, reach out to Fabiola here.