| Stormwater BMP | Illustration | Pollutant Removal Mechanism | Location in Treatment Train | Pollutant Removal 1 | Potential Application | Cost | Maintenance Requirements 3 | Space needed | Pretreatment 4 | Habitat Quality 5 |
|---|---|---|---|---|---|---|---|---|---|---|
| Dry swale or step pool | 
|
Sedimentation / Infiltration | Throughout |
TSS: Medium TN: Low TP: Medium Chloride: Low Metals: Medium Oils and Grease: Low Pathogens: Low |
Residential Commercial Industrial Highway/Road Recreational |
Low to medium (depends on components) | Simple‐Intensive | Small | Oil/Water Separator Sediment Basin (depending on watershed soil types, contributing drainage area, and potential for system fouling/plugging) | Low |
| Wet swale |  |
Sedimentation / Transpiration | Throughout |
TSS: Medium TN: Low TP: Low Chloride: Low Metals: Low Oils and Grease: Low Pathogens: Low |
Residential Commercial Industrial Highway/Road Recreation |
Low | Simple | Small | Oil/Water Separator | Low |
| Biofiltration Basin |  |
Sedimentation / Filtration | Beginning |
TSS: High TN: Low/Medium TP: Medium/High2 Chloride: Low Metals: High Oils and Grease: High |
Residential Commercial Retrofit |
Low $0.5‐$1.3 CF | Simple‐Intensive | Small to medium | Needed Oil/Water Separator, Vegetated Filter, Sediment Basin, Water Quality Inlets | Medium‐High |
| Permeable pavement with underdrain |  |
Filtration | Beginning |
TSS: High TN: Medium/High TP: Medium/High Chloride: Low Metals: High Oils and Grease: High |
Residential Commercial Ultra Urban Retrofit |
Medium 3‐10 CF | Medium | Small to medium | No Pretreatment Required | None |
| Tree Trench/Tree Box (with underdrain) |  |
Filtration, Transpiration | Throughout |
TSS: High TN: Medium/High TP: Medium/High Chloride: Low Metals: High Oils and Grease: High Pathogens: High |
Commercial Ultra Urban Retrofit |
High $1.80 ‐ $12.70 CF based on recommended soil volume of 1,414 CF per tree |
Intensive | Small to large | Needed Oil/Water Separator, Water Quality Inlets | Medium |
| Media filter (sand filter) |
|
Filtration | Throughout |
TSS: High TN: Medium TP: Medium/High Chloride: Low Metals: Medium/High Oils and Grease: High Pathogens: High |
Residential Commercial Industrial Recreation |
Low | Simple-moderate | Small | Needed Oil/Water Separator, Vegetated Filter, Sediment Basin | Low |
| Green roof |  |
Filtration | Throughout |
TSS: High TN: Low TP: Low Chloride: Low Metals: High Oils and Grease: High Pathogens: High |
Residential Commercial Ultra Urban Industrial Retrofit |
High | Moderate-intensive | Small | Low | Medium |
| 12 Low = < 30%; Medium = 30‐65%; High = 65‐100% 2Some media mixes can leach phosphorus. |
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