Virtua Voorhees Hospital

Challenge

According to township standards, the removal of trees with a DBH of 5 in or greater requires one-to-one replacement, which amounted to 5,700 replacement trees for phase 1 and phase 2 . Planting this many trees in the area surrounding the building, parking lots, existing wetlands, and detention basins was not feasible given the limited area available for planting. Additionally, local standards required regular planting forms, cultivated lawn, maintained landscape areas, and dense plant buffers to obscure views and buffer noise beyond the lot. These regulations were better-suited for small-scale suburban planting aesthetics and did not reflect the history, scale, or function of the site as a pine barren and wetland. Additionally, during site construction, installing an 11,000-ft sewer force main and 6,000 ft of gravity lines across the wetlands became a significant challenge.

Solution

The design team worked with local officials to adapt their landscape standards in order to create an aesthetic approach more consistent with site context. To do this, the landscape architects wrote responses to each applicable section of the standards and created section drawings to show how a native aesthetic would better serve this site and its scale. Existing ecological systems were preserved in significant portions of the property, which was far more valuable than merely replacing trees without concern for wildlife habitat. The design team considered the future health of the natural systems on-site and proposed a variety of plant species and sizes in other areas. More than 3,000 trees were ultimately planted on the site, and another 2,000 were planted elsewhere in the township. In the buffer zones where visual screening and noise control was important, the design fully met the requirement of “opaqueness.” In places where a degree of transparency was desirable, the design laid out partially-screened views to allow glimpses of the hospital in the distance or of the beautiful gardens on campus. To solve the sewer installation challenge during site construction, a portable diesel engine pump and a holding tank was temporarily used. The pump was transferred onto the sewer force main once the installation was complete.

• 127 new plant species were installed on site, and existing tree groves and wetland habitats were preserved.
• 500 pines and over 100 junipers that were preserved as part of the existing Pine Barrens on site. Dominant species include shortleaf pine (Pinus echinata), pitch pine (Pinus rigida), Eastern white pine (Pinus strobus), and Virginian juniper (Juniperus virginiana). A large portion of existing Eastern white pines were preserved, forming an alley when entering the site from the east that leads to the Pediatric Therapy Garden.
• 40 acres of wetlands make up about 17% of the site’s total area. Constructed wetlands were built to connect the existing wetlands on the north and east perimeters of the site with the aim of repairing the existing wetland ecosystem. 
• A series of courtyards, green roofs, newly-constructed wetlands, preserved wetlands, and preserved plant buffers compose a network of green infrastructure that efficiently controls stormwater runoff on the site. The newly-constructed wetlands serve as buffer zones, receive stormwater runoff from building rooftops, hardscapes and parking lots, and process and filter the water to minimize pollution before entering the preserved wetlands. 
• 3 primary green roofs bring calming views to the upper levels of the hospital. These elevated gardens mask the building’s considerable height and the resulting sense of removal from the ground below. The green spaces on rooftops and at-grade break the large footprint of the hospital into multiple masses, allowing the surrounding nature to become an integral part of the healing environment.
• Specific therapeutic design elements are incorporated on site. Movable furniture offers choice and enhances feelings of control, a balance of available quiet and active spaces caters to emotional and restorative needs, and designed microclimates promote patient comfort.
• Large common areas are used for gathering and dining. Due to the high-volume use of these outdoor spaces, the hospital has doubled the amount of outdoor furniture provided in order to accommodate the unanticipated level of activity.
• The pediatric garden features soft, rubberized paving, animal sculptures that double as play equipment, and low tables that serve as activity spaces for children. Ornamental grasses and trees activate senses of sound, touch, and sight.
• Natural, local materials are used throughout the hospital grounds to create an inviting and sustainable healing environment. Materials like stone and wood were selected to imbue the garden spaces with texture and warmth.
• 68% of the site is pervious, and 52% of pervious area is made up of green space. In total, about 32% of the site is covered by impervious materials.

• Understanding the site’s pre-development context and ecosystem services were crucial to the ultimate success of the landscape. This would not have been possible without the week-long site inventory conducted by the landscape architect before the design process began. Without this documentation, it would have been difficult to select areas for preservation and replant the site as successfully as was ultimately achieved.
• Multiple communication pathways with officials in the form of meetings, writing, and drawings allowed for the adaptation of design goals to fulfill city standards. 
• Oak, pine, and maple trees represented a majority of the species to be planted, but delays in the construction schedule caused it to not appropriately align with oak planting season in spring. The oak trees were eventually planted at the correct time in the spring after discussion with the client. Scheduling and effective communication played major roles in the project’s outcome.
• Green roofs require consistent seasonal maintenance to ensure their health. In this project, the green roofs were designed to be 4-in deep with no irrigation. A 6-in, irrigated green roof design may have achieved a higher standard of performance.

Paving: Stone Sources, Inc.; Hanover Pavers
Plants: LiveRoof, represented locally by Creek Hill Nursery;
Ernst Conservation Seeds, LLP
Structural Materials: Trinity, Chaplain Stone
Lighting: Bega; Kim Lighting, Inc.; Winona; Exceline
Site Furniture: Wausau Tile

Project Team

Landscape Architect, Architect, Structural Engineer, Electrical Engineer, Lighting Designer, Horticulture: HGA Architects and Engineers
Civil Engineer: Dewberry – Goodkind
Contractor: Turner Construction
Environmental assessment: Eidahl Environmental Design, Inc.

Role of the Landscape Architect

The landscape architects conducted a native plant inventory and provided guidance on choosing which existing site vegetation to preserve. They provided construction documents, construction administration and punchlists, and held team meetings to discuss design. The multidisciplinary firm was the lead on the project and also served as the architect, structural engineer, electrical engineer, lighting designer, and horticulturist.