Canadian Architect


1st Street SW Underpass Enhancement

December 1, 2012
by Canadian Architect

ARCHITECT The Marc Boutin Architectural Collaborative Inc. + el dorado inc (associated architectural firm)
LOCATION Calgary, Alberta

Calgary’s growth has always been linked to the Canadian Pacific Railway. Since 1883, the CPR corridor has been the heart of the city–symbolically, physically and economically. Today, the track corridor is embedded in the core of the city and although it continues to be a vital economic factor, the corridor also poses challenges for the ongoing development of communities which border the rail lines.

Unfortunately, the current physical state of deterioration of the 1st Street SW Underpass is in contradiction to its critical mobility and gateway functions. Accordingly, it was identified as a priority project for improvement by the City of Calgary. Connective, pedestrian-centred and multi-sensory, the redesigned underpass has the capacity to honour Calgarians’ collective history and poetically project into their future. At the same time, complexities of the context required the design be an inclusive, robust and serviceable part of the urban infrastructure. 

The realm of the underpass engages a very particular and poetic moment within the city. Users moving beneath the underpass leave one particular urban realm to re-emerge within a new and different condition; thus, the underpass represents a transition, a gateway between the downtown core to the north and the historic Beltline district to the south. Simultaneously, the bridge supports a complex network of railcar movement which geographically connects disparate eastern and western territories. As such, the centre of the bridge is a critical juncture where the simultaneity of local transition and geographical connection situate the city of Calgary as a liminal territory.

 The initial gesture, a layering of two folded skins, forms a composite wall assembly interdigitizing the mitigation of prevailing safety and comfort issues with the creation of a meaningful experience for the user. The outer skin serves to control the widespread water ingress issue; at the same time, large-scale imagescapes of rolling prairie and soaring mountains form the east-west thematic basis of a supergraphic film, applied to the front face of this layer. 

The inner skin, an anodized aluminum screen, is encrypted with large-scale wayfinding information which announces the upcoming urban district as users move north-south through the underpass. Perforations within the screen are choreographed to control legibility of the supergraphic behind; thus, connections to both geographical and urban conditions create a sense of anticipation beyond the confines of the underpass.

Three eras of construction throughout the life of the bridge create distinct zones within the pedestrian and vehicular realms, distinguishable both in terms of their structural logic and their impact on the visual connectivity between users. Coordinating the inner skin’s role (as lens or text) with the inherent structure of the underpass allows each bay to retain its unique character, while creating a new dialogue with the site.

Through notions of infrastructure as facilitator, and movement as catalyst, the viewer is empowered to create his or her own picture of “place” and is left to define a personal understanding of the underpass’s historic and contemporary meaning to the city at large. 

DC: The project operates with the necessarily infrastructural gesture of multiple (but unique) instances with a commitment to a delicacy of detail–by catering to dynamically oblique view angles, directions and speeds of experience in contrast to the industrial-strength civil monumentality above. This confluence of the various modes of city transport, complete with the inventive recapturing of the pedestrian realm, is a progressive game plan for delaminating disparate conditions into consolidated new urban spaces.

MCC: The strength of this project is revealed in its capacity to integrate a large-scale problem in the city with small-scale artistic materiality. Pedestrians will enjoy a lively experience while moving securely through the underpass, and the perforated screen will provide a constantly shifting perception dependent on changing viewpoints, resulting in a richly textured promenade.

BH: This intervention displayed a robust tectonic inventiveness harnessed to address the extraordinarily difficult design challenge of underpasses. Integration of light, graphics, and sophisticated material pixellation to create directionally distinct views point to a possibility of not just making an unpleasant urban touch point palatable, but actually invigorating.

Client City of Calgary, Land Use Planning + Policy
Architect Team The Marc Boutin Architectural Collaborative: Marc Boutin, Richard Cotter, Mike DeBoer, Nate Dekens, Jerry Hacker, Jonny Hehr, Jodi James, Jenny Kim, Sean Knight, Kat Kovalcik, Matt Lamers, Tony Leong, Alison MacLachlan, Michael McGie, Mauricio Rosa, Kristin St. Arnault, Liam Woofter. El Dorado: Josh Shelton, David Dowell, Brandon Froelich.
Structural Entuitive
Electrical Mulvey + Banani
Civil Delcan
Lighting Design Lighting Design Innovations (LDI)
Budget $1.5 M
Completion Fall 2013

Canadian Architect

Canadian Architect

Canadian Architect is a magazine for architects and related professionals practicing in Canada. Canada's only monthly design publication, Canadian Architect has been in continuous publication since 1955.
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