Regional Project Profile
Johnson & Johnson Pharmaceutical Research & Development LLC

Category: Implemented Design
Type of BMP: Porous pavement and underground infiltration gallery, bioretention swales, constructed stormwater wetlands

| Description | Location | Partners | Cost | Contact |
 

Integrated into Johnson & Johnson’s site expansion are the following stormwater Best Management Practices (BMPs): 1) Porous pavement and underground infiltration gallery; 2) Bioretention swales; 3) Constructed stormwater wetlands.

1) Porous Pavement and Underground Infiltration Gallery
Testing was conducted concluding that the site was suitable for the installation of both porous pavement and an underground infiltration gallery. Percolation testing determined that the infiltration rate would be 1.04 inches per hour and that the two elements would capture about 42% of stormwater volumes. For a diagram of a typical porous pavement section with underground infiltration gallery, please click here. The subsequent project phases to incorporate other BMPs like bioretention swales, wetlands, and other non-structural methods are meant to retain or filter the remaining run-off.

The construction of the porous pavement included the digging of divided subsurface water storage cells, measuring 60 feet by 60 feet by an average of 3 feet deep. These cells were lined with geotextile fabric. Before AASHTO No. 1 gravel was put in place, perforated pipes connected to the main storm sewer pipes were set at different grades to provide conveyance and diffusion of stormwater into the storage cells. Only one building under construction is presently hooked up to the system; per the master plan, the storage capacity of this reservoir anticipates all future run-off volume from buildings at subsequent stages of site development.

2) Bioretention Swales
When the underground infiltration gallery reaches its maximum storage capacity excess stormwater flows through a custom “upwell” pipe relieve system. The stormwater is filtered through graded vegetated swales before flowing into stormwater drains. Native shrubs, trees and ornamental grasses, all salt and moisture tolerant, were planted in the parking lot islands to both absorb stormwater volume and dissolve common pollutants from vehicular traffic. The swales were covered with decorative gravel (river stone) for maintenance purposes. The porous asphalt works so well that these swales do not encounter much run-off. For a list of native plants used on the islands in between the parking lot bays, please click here.

3) Constructed Stormwater Wetlands
This is a future project. Details will be added as they become available.
 

County:         Spring House, Montgomery County
Watershed:   Neshaminy Creek

The 101 acre Johnson & Johnson Spring House corporate campus is located at Welsh and Mckean Roads in Spring House and is the hub of East Coast clinical research development. Johnson & Johnson’s objective for the property was to mitigate the stormwater impacts in connection with the construction of future facilities. A 150,000 sq. feet clinical development, laboratory, and office space addition was announced in May 2007 and will finish construction in 2009. The incorporation of Best Management Practices (BMPs) reduces non-point site pollution and flash flooding in this prone area. These sustainable development practices will reduce the expansion project’s run-off levels by 15% compared to pre-development run-off rates. The porous pavement has been completed, but the bioretention swales and wetlands are currently under construction.