| Process | BMP | Comments |
|---|---|---|
| Infiltration | Low impact development/better site design/sustainable development | Includes such things as reduced street and sidewalk width, less curb and gutter drainage, scattered bioretention, shared pavement. |
| Trench or basin | Must be properly engineered in adequate soils; proper maintenance essential | |
| Perforated sub-surface pipes, tanks and storage systems | Expensive but effective and space-saving. | |
| Disconnected imperviousness | Includes primarily rooftop drains and roadway/parking surfaces | |
| Pervious (porous pavement) | Includes a number of paving and block methods, or simple parking on reinforced grassed surfaces. | |
| Bioretention (if contains infiltration element) | Some bioretention facilities are designed to infiltrate. | |
| Evapotranspiration | Bioretention (rain gardens) | Exposes runoff water to plant roots for uptake;can be under-drained and still effective. |
| Vegetated swales | Provides water a chance to soak into the ground and be filtered as it flows. | |
| Wetland/pond storage | Combination of standing water surface and vegetative root exposure yields volume reductions. | |
| Vegetated drainage corridor | Connecting numerous features increases opportunities. | |
| Recessed road/parking drainage | Routing paved surface runoff to vegetated sump areas keeps it out of receiving waters. | |
| Storage | Rain barrel/cistern | Small-scale runoff collectors keep water around for later re-use or slow release. |
| Rooftop (green roof) | Storage on a roof prevents water from leaving the site; combining with vegetation (engineered green roof) makes it even better. | |
| Wetland/pond storage | Combination of standing water surface and vegetative root exposure yields dramatic volume reductions. | |
| Conveyance | Vegetated swale | Provides water a chance to soak into the ground and be filtered as it flows. |
| Filter strips/buffers | Variation of vegetated swale with side slope protection. | |
| Landscaping | Low Impact Development/Better Site Design | Includes such things as scattered bioretention, shared pavement, native or prairie plantings. |
| Bioretention (rain gardens) | Exposes runoff water to plant roots for uptake, can be under-drained and still effective. |