Reuniting Chicago with the River that Runs Through It

Stretching along the south edge of Chicago River, the Riverwalk is a pedestrian-only open waterfront located a level below the adjacent streetscape. The famed redevelopment initiative to reclaim the Chicago River for the ecological, recreational, and economic benefit of the city was finally completed toward the end of 2016, after over a decade of planning.

Now known as the city’s “second lakefront”, the Riverwalk spans 1¼ miles through the heart of Chicago and provides a magnificent setting for walking, jogging, or simply sitting and enjoying the impressive view of the surrounding buildings that loom over the river.

The plan to create the riverside promenade was first envisioned by urban designer Daniel Burnham in the early 1900’s. The task at hand was a challenging one, with the design team required to work within a tight permit-mandated 25ft build-out space to expand the pedestrian area. Sasaki, Ross Barney Architects, Alfred Benesch Engineers, Jacobs/Ryan Associates, and a wider consulting team including GreenBlue Urban, were tasked with creating the eight-block continuous walkway along the river.

The first two block section completed was an immediate success, drawing office workers and nearby contractors down to the riverside to enjoy their lunch. It provided a much-needed getaway from the street-level commotion, and proposed an enticing tease of what the continuous waterside walkway would offer the dense downtown area.

Perhaps the most exciting element of the Riverwalk redevelopment is what the designers called the River Theater. This block-wide sculptural stairway features an amphitheater style staircase linking Upper Wacker Drive to the river.

The River Theater was conceived as a space where the streetscape folds down to the river in a smooth and polished manner. It offers pedestrian connectivity to the water’s edge, while trees provide greenery and shade. The area has the capacity to seat more than 750 people in the occurrence of riverside events or other happenings.

With the staircase developed in a repetitive, modular manner, it represented a good opportunity for precast concrete, which can be produced quickly and with consistent finish – all without the cost of paving stones. Stone steps are usually constructed by doweling tread-shaped blocks into a sloped concrete slab that supports them. The River Theater staircase was created in the same manner – a cast-in-place sloped slab which supports modular precast blocks that make up the terraces, stair treads, and path pavers.

Between the sloped slab and the marine structure below (the landfill and concrete enabling construction out onto the river), is a wedge-shaped void. Within it are three continuous, linear ArborSystem planting areas that support the 17 honey locust trees that punctuate the staircase. A water-harvesting system collects the River Theater’s drained stormwater in a structure under the sloped slab, which is stored and supplied as irrigation to the trees.