Corporate Campus Design

New Jersey Manufacturer's Insurance Group Campus

NJM Stormwater SystemsPrinceton Hydro was contracted by the NJM Insurance Group (NJM) to provide environmental, geotechnical and stormwater management design services for the construction of their new 55-acre corporate campus. Princeton Hydro worked with the project team to develop a concept plan that could be built within the context of proper stormwater management and meet the stringent requirements of the NJ Pinelands Comprehensive Management Plan.

Due to a number of site physical constraints, the site was designed to contain nearly all stormwater runoff on site, up to and including the 100-year frequency, 24-hour duration storm event. To accomplish this ambitious goal, the project infiltrates stormwater in a number of bioinfiltration basins, parking lot islands, a wetland basin, and a bioretention island. All infiltration areas were designed using a soil amendment process where the underlying soils were excavated and amended with organic material to improve the underlying recharge capabilities of the soils. Additionally, a 120,000 gallon below-grade rainwater capture and reuse system was designed which captures roof runoff for on-site irrigation.

During construction, Princeton Hydro provided monitoring services for all earthwork activities. Princeton Hydro staff was on site full time during critical activities of site work to ensure that the project was built in accordance with the intent of the original design and ensure the maintenance of the project schedule. Princeton Hydro geotechnical engineers reviewed shop drawings of subsurface structures and provided field engineering and consultation to the general contractor when field conditions differed from those anticipated.

The project is one of the first projects in NJ built to infiltrate nearly 100% of the on-site runoff and using site design based stormwater capacity to determine allowable impervious cover.