Thomas Jefferson University Lubert Plaza

The design for the site had to respond to multiple program demands and users, including students, faculty, hospital staff, and neighborhood residents/office workers. The program for the site called for passive recreation (eating, sitting, studying) and lawn space for active recreation (informal play, ball tossing, etc.) The university’s desire to include lawn areas would mean that the site would require irrigation. Because the plaza site is located 3 feet above a parking structure, it had all of the structural and planting constraints associated with rooftops.

Solution

The plaza is designed to accommodate academic events and ceremonies, as well as be inviting to the urban community with its public art and diverse, sunny and shaded seating areas. The plaza landscape demonstrates TJU’s commitment to sustainability by being irrigated in part by rainwater and air conditioner condensate, which are collected in an underground cistern. The elliptical forms radiating from the center make this space feel expansive despite being confined by tall buildings, and the openness of the design makes the plaza feel welcoming and secure.

• 1.6 acres of new park space overlay an underground parking structure. The new space accommodates multiple activities from studying to eating to play, whereas the former space was primarily dedicated to parking.
• The new plaza and lawn area increase pervious surfaces from 7% of the total site area to 40%.
• Organic materials and light-weight aggregates augment the engineered soil of the green roof to increase water-holding capacity.
• A 17,000 gallon cistern adjacent to Locust Street provides irrigation for trees and lawn. The cistern is approximately 12 ft x 159 ft and runs parallel to the sidewalk avoiding utilities and trees, with several ‘cut outs’ to avoid root conflicts.
• 53 new shade trees line the streets and embrace both the oval plaza at the center and the large event lawn.
• The new plaza adds valuable green space to this dense urban neighborhood and has become a social and environmental asset valued by both the University and the surrounding community.

• Post construction monitoring of plant performance and irrigation demands indicate that light weight soils require more water than most other soils.
• An organic management program was instituted post-occupancy to address plant health. Irrigation refinements continue. These are just two of the factors pointing toward the importance of involving the landscape architect post-occupancy for a project’s health and sustainability.
• Survey respondents indicate that they would like more water in the plaza, and site furnishing, such as tables. Water and comfort are highly appreciated in the urban setting and landscape architects should be cognizant of this. As the plaza evolves it may be possible to include these elements.
• Most survey respondents were unaware of the site’s benefit to the urban stormwater infrastructure. The performative function of landscape is of interest to the public and helps support the role of landscape architects in environmental design. Future design could make the stormwater performance aspect of the plaza more visible and readily grasped by the public.

Project Team

Landscape Architect: Andropogon Associates, Ltd.
Architect: Burt Hill Architects
Irrigation Design: Irrigation Consulting, Inc.
Cost Estimator: P. Agnes, Inc.
Civil Engineer: Barton and Martin Engineers (Stantec)

Role of the Landscape Architect

The landscape architect performed landscape design including planting, circulation, lighting, and grading, soils design, comprehensive stormwater management coordination, coordination and design of stormwater cisterns and irrigation systems, and soil and plant landscape maintenance assistance.