A wet pond is a permanent pool where stormwater is captured and regulated by an elevated outlet structure. Native vegetation should be used to provide a permanent buffer around the pool. Water from the pond should be used for irrigation or some other beneficial use. Wet ponds are used to accommodate runoff and provide stability… Read More »
A vegetative filter strip is a gently sloping landscaped area that provides pretreatment to an adjacent stormwater management facility. The BMP slows the upstream runoff rate, reducing the risk of erosion and allows for quicker infiltration before the water leaves the site. Vegetative filter strips add visual buffer from impervious areas such as parking lots.… Read More »
A subsurface gravel wetland is a system containing both a subsurface gravel bed and a surface marsh. Stormwater runoff is infiltrated through the marsh into the gravel bed. The gravel bed filters pollutants and conveys water to an outlet structure. Considerations: The NJDEP recommends allowing wetlands plants to establish prior to system operation. Liners may… Read More »
A constructed wetland is an engineered wetland system that can be used to reduce peak flows and meet water quantity regulations. Constructed wetlands have the added benefit of removing a wide variety of pollutants through settling and vegetative filtering, providing wildlife habitat, and adding aesthetic value to a site. Considerations: The vegetation and biological processes of… Read More »
A sand filter is a depression in the ground used to capture, infiltrate, and filter pollutants before discharging. Sand filters are similar to infiltration basins in design. The primary difference is that sand filters can have vegetative cover and are less aesthetically obtrusive. Sand filters can be constructed with or without underdrains. Like bioretention systems… Read More »
Pervious pavement is a surface that allows water to infiltrate into the ground below. Pervious pavement materials can include asphalt, concrete, interlocking concrete pavers, gravel, and resin-bonded materials such as recycled rubber, mulch, and glass. These surface courses are installed over a supporting base of crushed stone that helps to store and infiltrate stormwater. Pervious… Read More »
A manufactured treatment device (MTD) is a structural alternative to treating water quality on a site. This approach to treatment can be used when space is limited. MTDs are designed to remove chemical contaminants and sediment from runoff through filtration, vortex separation, and/or other technologies. Considerations: MTDs are most effective for small drainage areas. Separation… Read More »
An infiltration basin captures stormwater and infiltrates it into the ground through highly permeable soil media designed to remove pollutants and promote groundwater recharge. The soils in these systems treat pollutants via settling, filtration, and biochemical activity. Like bioretention systems and sand filters, infiltration basins are more effective at providing water quality treatment and groundwater… Read More »
A grass swale is a long, narrow grassy channel used to convey stormwater to a downstream green infrastructure practice or storm drain. Grass is typically kept to a height of about three to six inches to slow down the runoff and allow any debris or sediment to settle out without interfering with the direction of… Read More »
Extended detention basins are surface depressions that temporarily store stormwater runoff. The slower drain time allows sediment to settle to the basin bottom before water discharges. The amount of water quality treatment is dependent upon the detention time. Considerations: Sediment will accumulate at the basin bottom. Designing systems to accommodate more volume than required can… Read More »
A dry well is a subsurface stormwater facility consisting of either a structural chamber or stone filled excavation that is used to collect and temporarily store stormwater runoff from rooftops. The dry well inflow is connected by roof leaders. The sides and top of the dry well are completely lined with filter fabric to avoid… Read More »
Cisterns are storage tanks designed to capture and store stormwater for non-potable uses such as irrigation, toilet flushing, or industrial processes. Stormwater runoff is typically carried from roof areas to cisterns through roof gutters, downspouts, drains, and/or pipes. Screens on gutters and downspouts filter large sediment and debris from stormwater runoff before it enters the… Read More »
Blue roofs are non-vegetated systems that hold stormwater. They can be designed as modular trays with loose stones, specialized permeable pavers, or just a waterproof membrane. Benefits include: Better temperature regulation on the roof surface Lower building heating and cooling costs Minimizes land used for stormwater management, allowing for more recreational and public space area… Read More »
Bioretention systems are vegetated depressions in the landscape designed to infiltrate stormwater into the subsoil, and/or hold it for a period of time to settle out pollutants and allow some uptake by plants. Bioretention basins can be sited in a wide range of different locations and settings. The terms “rain gardens” and “stormwater bumpouts” are… Read More »
The Developers Green Infrastructure Guide 2.0 breaks down New Jersey’s Stormwater Rule amendments and helps developers and decision-makers understand more clearly green infrastructure options and advantages, compare alternatives, evaluate costs and benefits.
The Developers Green Infrastructure Guide 2.0 is brought to you by the Developers Green Infrastructure Task Force, a partnership between New Jersey Future and the New Jersey Builders Association.
The Task Force gratefully acknowledges the financial support of the William Penn Foundation, which made this project possible.
