Green infrastructure isn’t rocket science, but proper design, construction, and maintenance – all essential to long-term success – require a different approach.
View new development and retrofit demonstration project examples.
A number of innovative green infrastructure installations can be found in new development and redevelopment in New Jersey. Here are some examples.
Sustainable Jersey awards points for a pilot green infrastructure project and, separately, for implementing green infrastructure projects that satisfy the short-term and, later, long-term goals identified in the companion planning action. Find Out More
The American Society of Landscape Architects features 40 case studies illustrating the transformative effects of sustainable landscape design and the use of green infrastructure practices across the country.
Green infrastructure best management practices (GI BMPs) are exceptionally adaptable and can be used in a variety of environmental and land development settings, whether urban, suburban or rural. They also work to control, treat and manage runoff generated from new development and can be integrated easily into existing conventional stormwater collection systems to take pressure off of undersized and aging gray infrastructure, and improve management of stormwater generated from existing development.
Many GI BMPs are designed to work with relatively small catchment areas (drainage areas) to manage the water quality event (1.25 inches of rainfall in two hours) completely, as well as the first flush of larger storms. This is why utilizing GI BMPs in a decentralized stormwater management setting is desirable. This means utilizing a number of small GI BMPs to collect and manage runoff as close to the point of generation as possible. Routing too much runoff through certain types of GI BMPs can compromise the performance of the system and result in scour and erosion impacts to the BMP. This does not mean that GI BMPs can’t be used for large developments. It only means that they need to be sized and sited properly in order to be effective. The more commonly utilized GI BMPs are highly scalable, meaning that they can be utilized to control, treat and manage runoff generated from both small and large catchment areas. This applies to bioretention basins, infiltration basins, constructed wetlands, and bioswales. The New Jersey Department of Environmental Protection’s Stormwater Best Management Practices Manual provides detailed guidance on the design and construction of green infrastructure BMPs. Design and construction guidance is also available through Rutgers Cooperative Extension Service. In fact, there are numerous excellent resources detailing how to design, construct, and maintain GI BMPs. This bears repeating: As is the case with conventional gray infrastructure, it is possible to design, size and construct GI BMPs for a wide variety of applications: big or small catchment areas, new development or redevelopment. In every application, it is imperative that correct site data be collected in advance of implementing a particular GI BMP. This includes but is not limited to:
In every case, all of a site’s characteristics must be accounted for and sound hydrologic and hydraulic data must be developed before selecting a specific GI BMP.
The following image (click to enlarge) provides general guidance when analyzing an existing suburban site for potential green infrastructure retrofit opportunities.
The following should be considered a general guideline to the selection and application of GI BMPs.
Redevelopment or Retrofit
Need To Reduce Nutrients
High Contaminant Area (e.g., gasoline filling station)
Need To Maximize Recharge
Green infrastructure features should become integral to your capital project designs (roads, parks, schools, libraries), and should be reflected in contract specifications and the capital budget. GI doesn’t always cost more, but sources of grants and low-interest loans abound.Find Grants & Loans
Resources & Strategies:Grant Writing Module
One of the best ways to fund green infrastructure is through stormwater utilities, programs that charge a fee based on the impervious cover on a given property. Not only do the fees raise money for state green infrastructure projects, they also provide a mechanism to incentivize green infrastructure projects on individual properties. Stormwater utilities are an option for municipalities in 40 states, including New Jersey since March of 2019. To learn more about stormwater utilities in New Jersey, please visit New Jersey Future’s Stormwater Utility Resource Center..
The New Jersey Stormwater Best Management Practices Manual (BMP Manual) is developed to provide guidance to address the standards in the state’s Stormwater Management Rules, N.J.A.C. 7:8. Revised or new chapters of the BMP Manual (Chapters 5, 12 and 13) available on NJDEP’s website.
This document provides guidance to combined sewer overflow (CSO) permittees within the State of New Jersey – that is, the 21 cities that have combined stormwater and wastewater systems – to evaluate green infrastructure as part of their required Long Term Control Plans (LTCPs).
The manual, created by the Rutgers Cooperative Extension (RCE) Water Resources Program, provides a wealth of information for planning and design professionals, municipal engineers and officials, community groups, and inspired residents who are interested in installing green infrastructure practices to reduce the negative effects of stormwater runoff.
The Urban Street Stormwater Guide provides cities with national best practices for sustainable stormwater management in the public right-of-way, including core principles about the purpose of streets, strategies for building inter-departmental partnerships around sustainable infrastructure, technical design details for siting and building bioretention facilities, and a visual language for communicating the benefits of such projects.
New Jersey Future organized a panel on June 5, 2019 at the NJ Society of Municipal Engineers quarterly meeting where Clay Emerson presented on “Green Infrastructure: “Coming to a Plan Set Near You.”
New Jersey Future organized a panel on March 14, 2017 at the NJ Society of Municipal Engineers quarterly meeting where James Purcell presented on “Porous Asphalt Pavement for Storm Water Management.”
There are a number of quantitative tools that engineers and other design professionals can use to document the pollutant load reduction benefits of green infrastructure BMPs. The choice of which tool to use is largely a function of a project’s goals.
There are a variety of hydrologic/hydraulic computer programs commonly used by engineers, environmental scientists and hydrologists to design and size green infrastructure BMPs correctly. Most of these programs are based on modeling methodologies developed by the NRCS and USDA; specifically, Technical Release 20 (TR-20, 1965) and Technical Release 55 (TR-55, 1975). Public-domain software such as the NRCS WinTR-20 or NRCS WinTR-55 provides basic modeling functionality and can be downloaded for free. Commercially available software including HydroCAD from HydroCAD Software Solutions or Pondpack from Bentley Systems include NRCS unit hydrograph methodology along with robust design and analysis features. When necessary or desirable, there are also more sophisticated approaches readily available, including:
Each of these techniques can be used to quantify the pollutant reduction, expressed either as a load (lbs/yr) or concentration (mg/L) expected as a result of the implementation of one or multiple green infrastructure BMPs used independently, in combination or in series at a specific site or over an entire watershed. Of the six identified techniques, MapShed and SWMM are the most robust. These modeling techniques enable one to compute a pre-development load and a post-development load with and without BMPs. They are also capable of computing pathogen (fecal coliform) levels and include parameters that account for loading from waterfowl, farm animals, domestic pets, and eroding stream banks, which often are a major contributor to suspended solids and nutrient levels in urban and suburban settings.