By Linda Harris, Center City District Philadelphia

As construction continues on the renovation of Dilworth Plaza, people who observe only the street level sometimes remark that it doesn’t seem as if much is happening. But that’s because the bulk of the work underway right now is beneath the surface, creating the foundation and the systems that will support the spectacular surface-level plaza that will be completed in 2014.

Artist’s rendering of Janet Echelman’s sculpture Pulse

The underground preparations include working around three operating transit lines while carrying out the installation of water lines, air lines, pumps, valves, lighting and controls that will be needed to propel the colorful steam mists of Janet Echelman’s original public sculpture, Pulse, which will be showcased in the new Dilworth Plaza.

Using five-foot-tall, moving columns of atomized water, Pulse will reflect in real time the movements of the transportation systems below, using the designated colors of SEPTA’s transit lines that carry workers, residents and visitors throughout the city via the City Hall hub.

Echelman’s sculpture is inspired not only by the transit lines, but also by the history of Center Square, where City Hall now stands, which previously was the site of the city’s first steam-powered waterworks. Pulse also pays tribute to the giant headhouse that stood across the street and, until 1950, was the downtown terminus for the steam-powered Pennsylvania Rail Road locomotives.

A reservoir for the water to be used by the 11,600-square-foot fountain that will be home to Pulse is under construction as well as a giant trough in which the sculpture will sit. Six pumps will distribute the water in the reservoir to create colored mists signifying the Broad Street subway line (orange), the Market-Frankford Line (blue) and the Subway-Surface Trolley to West Philadelphia (green). Valves that open and close a mister will create the movement signifying the arrival or departure of the trains below.

A prototype of Pulse is due to arrive in Philadelphia in late December.

Commissioned by the Center City District, Echelman’s work will create both a playful and animated embellishment on the fountain for this transportation hub at the center of a system that brings 300,000 passengers into Center City each day. The installation of Pulse will ensure that the $50 million transformation of Dilworth Plaza will become a memorable public space, thanks to support from the John S. and James L. Knight Foundation.

The $400,000 grant to the Center City District, which will enable the installation of Echelman’s sculpture, is part of the John S. and James L. Knight Foundation’s Knight Arts Challenge, a $9 million initiative funding innovative projects that engage and enrich Philadelphia’s communities.

Construction on Dilworth Plaza began in January 2012, and will be completed in spring 2014. The plaza will be transformed from an inaccessible, multi-level, unattractive, hard-surface plaza into a sustainable, well-maintained, green public space with no stairs or barriers from the street. The new plaza will have a large lawn, tree groves, a programmable fountain showcasing Echelman’s artwork, and a café with outdoor seating.

The Center City District, a private-sector organization dedicated to making Center City Philadelphia clean, safe and attractive, is committed to maintaining Center City’s competitive edge as a regional employment center, a quality place to live, and a premier regional destination for dining, shopping and cultural attractions.

Find us at www.centercityphila.org, Facebook, and Twitter @ccdphila. For photos, videos, and more information about Dilworth Plaza and Janet Echelman’s artwork, please click here.