Duluth Harbor Baths

The Duluth Bayfront is a mile-long stretch of vacant postindustrial harborfront which acts as a no-mans land at the center of the linear hillside city. Wedged between the expansive harbor to the south and a protruding granite hillside to the north, the flat treeless site is a man-made landscape consisting of concrete sea walls, wooden piles, and in-filled dredge material from the shipping channels. 

This project aims to address how programmatic and architectural interventions considered within a broader strategic framework can act as a catalyst for reframing this materially harsh, physically exposed, and monumentally scaled landscape as a place for rich human activities and experiences.

Project Inquiry

The Duluth Bayfront is a mile-long stretch of post-industrial harborfront located centrally along the linear city. The vast and largely vacant landscape acts as a no-man’s land between the steep granite hillside to the north and the endless expanse of water to the south.

This project aims to address how strategic programming and a single architectural intervention, considered within a broader urban vision, can act as a catalyst for reframing a post-industrial landscape as a place for rich human activity and experience. The project attempts to negotiate via architecture the gap between the scale of the human and the abstract scalelessness of the constructed harbor landscape, simultaneously celebrating its dramatic qualities while making spaces for social and reflective activities.
Urban Context

The city of Duluth exists due to its geographically strategic location and its geologically dramatic character. Located on the western-most tip of Lake Superior and near the geographical center of North America, the city was founded as a major shipping center for the trade of raw natural resources. Yet the city would not exist if it were not also for the steep hillside upon which it is built, which provides dramatic views over an endless expanse of freshwater. The exceedingly flat city of Superior, Wisconsin, located along the southern shore of the Lake, would have been the far more pragmatic site for the establishment of the major shipping and railroad center, but it was Duluth that was chosen due to the romantic drama of it’s unique perch above the Lake.

While the hillside and waterfront were the impetus for the city’s establishment, they were also the key determinants of its extremely long, narrow urban form. The railroads, which made the development of the city possible, were constructed along the relatively flat floodplain of the St. Louis river.  With the rise in the shipping trade, the marshy riparian landscape was dramatically transformed into an artificial landscape of long linear shipping slips and flat featureless railyards. This constructed landscape was defined by massive concrete seawalls built upon densely spaced wooden piles driven deep into the river bed and in-filled with dredge material from the adjacent shipping channel. Built upon this abstract landscape were massive, discrete industrial structures for storing and moving immense amounts of ore, coal, grain, powder cement, and other raw natural resources.

Concurrent with the development of the industrial harborfront, early city leaders made the visionary decision to set aside large sections of the hill’s ridgeline as a parkway network for recreational use.  The city’s commercial districts and residential neighborhoods subsequently developed within the one-mile wide gap between this scenic ridgline parkway and the economically pragmatic industrial harborfront.
Site Context

The site for this design inquiry is located at the point where the scenic hillside juts out to meet the industrial waterfront.  The exceedingly steep geological feature known as “Point-of-the Rocks” protrudes out toward the water, acting as a pinch-point that separates the historically blue-collar industrial neighborhoods along the St. Louis River from the more affluent business and residential neighborhoods along the lakefront.

With the slow decline of shipping and industry following WWII, the site underwent a graduat shift from industrial harbor use to civic, cultural, and recreational use.  In the 1960s, The Duluth Entertainment and Convention Center was built on the northeastern most sections of the Bayfront, followed in subsequent decades by a large outdoor performance space and a freshwater Aquarium.

With several new projects currently being proposed to city leaders, along with the recent closing of one of the two remaining industries along the Bayfront, there is an opportunity to address the historical and strategic significance of this stretch of land and how to best orient future development over the short and long term. While the site may appear to be something of a blank-slate for private development, it is a very consequential landscape due of its historical significance and access to the shoreline.

However, unlike other harborfront redevelopment projects in cities like Seattle or Toronto, Duluth’s lack of significant economic or population growth over the past three decades makes a wholesale urban redevelopment unlikely at present. Furthermore, the site’s physical disconnection from the hillside due to the rail and highway transportation corridor makes a truly seamless urban integration of the site physically and economically difficult.
Urban Strategy

The urban masterplan proposal aims to provide a framework for immediate and future development based on the concept of a programmed park organized around axis of movement with strategic program nodes located at key intersections. The Civic Axis connects the Daniel Burnham designed city government complex on the hillside to the Convention Center and Aquarium along the harborfront via a new landscaped bridge that completes Daniel Burnham’s unfinished urban plan.  The  Transportation Axis connects the new highspeed train station located along the rail corridor with a new marina and boat terminal in the adjacent harbor slip.  Finally, a new Park Axis allows for a more deliberate and considered transition between the ridgeline trail system and a new pedestrian Harborfront Axis which connects to the exising lakewalk trail to the north and the proposed riverfront trail to the south.  Along each axis, individual program nodes are proposed to activate the vast landscape with human activity.

Formally, the scale of the urban site has been broken down through a re-excavation of the historic shipping slips. Bringing back these water slips either in their entirety, as fragmented water feature, or as remanent outlines within a landscape, allows for a breaking down of the scale of the urban site, while creating strips of land and water that are simultaneously understood as relating to the historic logic of the site while providing much needed spatial definition within an otherwise unarticulated landscape.

Programmatically, the existing outdoor performance space, which currently encompasses an area double the size of the Millennium Park Pavilion in Chicago, has been re-scaled and moved to site adjacent to the Aquarium in order to bring a critical mass of cultural program to the more developed northern end of the Bayfront.  The remaining space to the south has been designated as a new centrally located farmers market (which the city currently lacks) and an open greenspace with a terraced landscape down to a newly designated water recreation slip. Located across the recreational slip from the park is a proposed harbor swimming and bathing facility consisting of an expansive outdoor “slip pool”,  locker and changing facilities, an indoor lap pool,  children’ play pools, and a bathing facility housed within four vacant silo structures at the opposite corner of the site.

Of the proposed programmatic interventions, the harbor swimming and bathing facility was identified as a project with  not only short-term viability but also long-term potential to act as a catalyst for future development on the site, as well as a powerful symbol for the city’s shifting identity. Furthermore, the kinetic qualities of swimming and haptic qualities of bathing offer rich opportunities for negotiating the scalar, material, and thermal qualities of the site.
Building Strategy

Architecturally, the design of the harbor swimming and bathing facility takes its cues from the logic of the landscape itself, specifically the use of concrete seawalls and retaining walls to define space. However, rather than being used to contain dredge material, grain, or powdered cement, the simple linear walls are used to define spaces for human habitation. Initially appearing as low landscape element which define pathways and spatial edges, the walls gradually shift in height to become architectural walls which define interior programmed spaces.

Considered as a field condition rather than a discrete building, the careful arrangement of seemingly parallel walls provide a variety of pathway through or over the swimming complex.  Access to the slip pool is made as open as possible, with the long, wide wooden boardwalk and kayak launch tapering to become a sun-deck and pool’s edge. Running parallel to the slip pool is the long, linear slip building containing an information office, public lockers, and individual changing stalls. The glazed east-facing facade of the building allows for visual continuity between the public exterior and semi-public interior while maximizing sunlight for early morning swimmers and providing shade on hot summer afternoons. The seemingly parallel concrete retaining wall that defines the interior space of the building is actually shifted in plan three degrees in order to both accommodate increased activity toward the water’s edge and create a sense of visual expanion as one moves in that direction.

On the exterior, this wall defines the eastern edge of the primary entrance.  The taller wall of the indoor pool building defines the opposite edge of the protected plaza space which in this case compresses rather than expands as one moves toward the water, creating a transitional zone from the vastness of the exposed landscape to the shelter of the building. Starting at twenty-four feet apart, the walls eventually tapper to a distance of only 8 feet at the water’s edge which contains small exterior heated pool with a vertically framed view out onto the harbor.

The indoor pool facility is defined by parallel walls spanned by four-foot deep and eight-inch thick concrete beams. The vertical surfaces of the beams reflect a rhythmic pattern of natural light onto the lap pool below through thin linear skylights. While the walls are in fact parallel, the ceiling angles upward toward the water’s edge to a frame a monumental view of the harbor and bring in ample natural light during the winter for passive heating. Bisecting the space is an exterior ramp which bridges over the slip and pool facilities as part of the larger harborfront trail. This ramp creates a visual connection between the recreational swimming activities of the pools and the land-based recreational activities of the city’s trail system. Furthermore, the ramp acts as a buffer between the indoor lap pool along the water’s edge and the more protected children’s play pools.

The floor of the exterior harbor promenade becomes the ceiling of a submerged trench that connects the swimming facilities to the bathing facility housed within the retaining walls of the existing cement silos at the opposite corner of the site. One silo remains untouched as part of a ruins park with the three remaining silos cut at various heights to respond to particular lighting qualities desired for each of the three bathing programs. The shortest silo, cut to a height of twenty-four feet contains a light-filled circular lobby space surrounded by men’s and women’s changing rooms along the perimeter. The changing rooms open out into the diamond shaped interstitial space between the four silos with openings to the steam silo to the right and sauna silo to the left. The steam silo is the formal inverse of the lobby silo, with an enclosed cylindrical steamroom structure located in the center surrounded by a curved circulation space along the perimeter. The ceiling of the steamroom contains a radially grided pattern of glass block openings which speak to both a pragmatic industrial perforation and the more romantic tradition of the Turkish baths.  A long curved stairway brings bathers to the roof which functions as a cooling deck.

Finally, the sauna silo retains a similar positive-negative relationship as the steam silo but in this case a square sauna structure sits within a circular terraced landscape. Rather than light streaming in from above, the sauna looks out on the dramatic harbor landscape through a rectangular opening in the silo shell. A square plunge pool mirrors the footprint of the sauna structure and bridges the threshold between interior and exterior environments.

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