Borden Park Natural Swimming Experience

The City of Edmonton’s Natural Swimming Experience (NSE) will be the first chemical free public outdoor pool to be built in North America. A 1,640m² programmed site supporting an 800m² building, the NSE will be a signature landmark element within the on-going transformation of the historic landscape of Borden Park. The NSE replaces an existing pool built in the 1950s with a pavilion and landscaped pool precinct for 400 swimmers during the fair-weather seasons and, during the colder months of the year, for the activities associated with outdoor ice-skating.

The compositional organization of the NSE’s combined built and landscaped elements follows the axial relationships established within the larger park setting. The low rectilinear building profile reinforces the sensation of open-sky spaciousness and the horizontal character of the existing park landscape. In contrast the architecture, at the discrete level of user experience, employs a minimal yet materially rich palette to achieve a distinct layering of elements. The aim is to create ease of movement through various functional aspects of the building and to enhance the narrative experience of moving through the programmed landscape internal to the NSE precinct. The building’s gabion walls, the puncture-like openings, and the thin-line demarcating the roof parapet contrast dramatically with the broad gestures of the sand and pebbles of the beach and the flush-to-surface planes of the pool precinct. This juxtaposition of the granular with the elemental invokes comparisons with the geology of the North Saskatchewan River and the flat topography of the prairie lands edge.

The rigor brought to the architecture that houses family change rooms, showers, washrooms, staff areas and the mechanisms associated with the filtration system takes its cue from the two mid-century modernist style pool buildings that remain on site. Built in the 1950s, during an earlier episode in the Borden Park transformation, these extant buildings now connect the new to a century old cultural heritage while also anchoring the northeast quadrant of the pool precinct. The swimming program includes a children’s pool, a deep pool, on-deck outdoor showers, a beach, picnic areas, and spaces for other pool related recreational activities.

A Natural Swimming Experience (NSE) is a balanced ecosystem where plant materials, microorganisms, and nutrients come together within a filtering process to create living water. This is an unsterilized, chemical and disinfectant free filtering system in which isolating membranes contain water as it is cleansed by means of a natural process. The water circulates via a feedback loop comprised of various components, from the deck side gravel filtered submersive pond to the planted hydrobotanic pond before passing through a PO4 adsorption unit within the building. There is no soil involved in this process. Filtration is achieved in two ways: by means of a biological-mechanical system or the constructed wetland and gravel filter, and in situ, with Zooplankton.