{"metadata": {"source_document": "NJ BMP", "version_year": "2026", "chapter_subchapter": "Chapter 4", "citation": "BMP 2026, Ch 4, p. 2", "topic": "Table 4-1:"}, "programmatic_checks": {}, "content_markdown": "# Stormwater Pollutant Removal Criteria\n\n## Table 4-1:\n\n|  Scenario | Is this a motor vehicle surface?  |\n| --- | --- |\n|  An outdoor surface parking lot comprised of gravel, grass paver blocks and/or turf grass where motor vehicles will drive or park | Yes  |\n|  An outdoor parking lot comprised of pervious asphalt pavement | Yes  |\n|  Landscaped areas in an outdoor parking area where no motor vehicles will drive or travel upon | No  |\n|  An open grass lawn reserved for use as an overflow parking area | Yes  |\n|  An outdoor parking lot where parking spaces are covered by a shade structure, such as a cantilever shade or canopy | Yes  |\n|  Parking surface inside a three-level parking garage | No  |\n|  Parking surface on the roof of a three-level parking garage | Yes  |\n|  Underground garages that are enclosed by walls | No  |\n|  A building roof as a parking area for motor vehicles | Yes  |\n|  An access road that is gated and accessible to motor vehicles only in an emergency | No  |\n|  Grass areas in a golf course that are only intended to be used by golf carts, grass mowers and pedestrians | No  |\n|  Paved or gravel areas in a golf course that will be used by maintenance trucks | Yes  |\n|  Artificial turf fields that are not intended to be used by motor vehicles | No  |\n|  Tennis courts with synthetic surfaces that are not intended to be used by motor vehicles | No  |\n|  Walkways along the driveways in a proposed development | No  |\n\nSource context and notes:\n\n# Stormwater Pollutant Removal Criteria\n\nSource revision: January 2026.\n\nTable 4-1:\n\n\n|  Scenario | Is this a motor vehicle surface?  |\n| --- | --- |\n|  An outdoor surface parking lot comprised of gravel, grass paver blocks and/or turf grass where motor vehicles will drive or park | Yes  |\n|  An outdoor parking lot comprised of pervious asphalt pavement | Yes  |\n|  Landscaped areas in an outdoor parking area where no motor vehicles will drive or travel upon | No  |\n|  An open grass lawn reserved for use as an overflow parking area | Yes  |\n|  An outdoor parking lot where parking spaces are covered by a shade structure, such as a cantilever shade or canopy | Yes  |\n|  Parking surface inside a three-level parking garage | No  |\n|  Parking surface on the roof of a three-level parking garage | Yes  |\n|  Underground garages that are enclosed by walls | No  |\n|  A building roof as a parking area for motor vehicles | Yes  |\n|  An access road that is gated and accessible to motor vehicles only in an emergency | No  |\n|  Grass areas in a golf course that are only intended to be used by golf carts, grass mowers and pedestrians | No  |\n|  Paved or gravel areas in a golf course that will be used by maintenance trucks | Yes  |\n|  Artificial turf fields that are not intended to be used by motor vehicles | No  |\n|  Tennis courts with synthetic surfaces that are not intended to be used by motor vehicles | No  |\n|  Walkways along the driveways in a proposed development | No  |\n\n\n\"Reconstruction\" means the replacement, rebuilding, or restoration of a lawfully existing structure. In the context of other terms and conditions in the rules, reconstruction can be further clarified as follows:\n\n- The rules exclude milling, repaving, or resurfacing of existing pavement from the definition of disturbance. Accordingly, milling, repaving, or resurfacing existing pavement as maintenance for an existing development will not constitute reconstruction.\n- Any work that extends beyond milling, repaving or resurfacing is reconstruction of a motor vehicle surface.\n\n[Source PDF](SOURCE.pdf#page=2)"}
{"metadata": {"source_document": "NJ BMP", "version_year": "2026", "chapter_subchapter": "Chapter 4", "citation": "BMP 2026, Ch 4, p. 3", "topic": "Table 4-2:"}, "programmatic_checks": {}, "content_markdown": "# Stormwater Pollutant Removal Criteria\n\n## Table 4-2:\n\n|  Scenario | Whether the stormwater runoff quality standards are applicable  |\n| --- | --- |\n|  The proposed redevelopment will replace the existing buildings and sidewalk with a 2-acre warehouse, rebuild the 2-acre parking area at the same location and leave the wooded and grass area undisturbed. | The project will result in reconstruction of 2 acres of motor vehicle surface and is subject to the stormwater runoff quality standards.  |\n|  The proposed redevelopment will replace the buildings and sidewalk with a 1.5-acre warehouse, rebuild the 2-acre parking area and increase the wooded and grass area from 1 acre to 1.5 acres. | The project will result in reconstruction of 2 acres of motor vehicle surface and is subject to stormwater runoff quality standards.  |\n|  The proposed redevelopment will replace the buildings and sidewalk with a 2.5-acre warehouse, replace the existing 2-acre parking area with a 1.5-acre parking area and the wooded and grass area will remain at 1 acre. | The project will result in reconstruction of 1.5 acres of motor vehicle surface. As a result, the 1.5-acre motor vehicle surface is subject to stormwater runoff quality standards.  |\n|  The proposed redevelopment will replace the buildings and sidewalk with a 1-acre warehouse, replace the existing 2-acre parking area with a 2.5-acre parking area and increase the wooded and grass area from 1 acre to 1.5 acres. | The project will result in an increase of 0.5 acres of regulated motor vehicle surface and a reconstruction of 2 acres of motor vehicle surface. As a result, 2.5 acres of motor vehicle surface are subject to stormwater runoff quality standards.  |\n|  The proposed redevelopment will replace the buildings and sidewalk with a 2-acre warehouse, resurface the top asphalt of the existing 2-acre parking area and the wooded and grass area will remain at 1 acre. | Resurfacing the existing 2-acre parking area is not considered reconstruction of motor vehicle surface. Therefore, the 2-acre parking area is not subject to stormwater runoff quality standards.  |\n\nSource context and notes:\n\nSource revision: January 2026.\n\nBelow is a hypothetical redevelopment site to illustrate different scenarios of reconstruction of a motor vehicle surface.\n\nA 5-acre redevelopment site consists of 1 acre of woods and grass, 2 acres of non-motor vehicle impervious surface, including buildings and sidewalks, and 2 acres of parking area. Different redevelopment scenarios in Table 4-2 illustrate that different redevelopment proposals may result in different scopes of applicability of the stormwater runoff quality standards.\n\nTable 4-2:\n\n\n|  Scenario | Whether the stormwater runoff quality standards are applicable  |\n| --- | --- |\n|  The proposed redevelopment will replace the existing buildings and sidewalk with a 2-acre warehouse, rebuild the 2-acre parking area at the same location and leave the wooded and grass area undisturbed. | The project will result in reconstruction of 2 acres of motor vehicle surface and is subject to the stormwater runoff quality standards.  |\n|  The proposed redevelopment will replace the buildings and sidewalk with a 1.5-acre warehouse, rebuild the 2-acre parking area and increase the wooded and grass area from 1 acre to 1.5 acres. | The project will result in reconstruction of 2 acres of motor vehicle surface and is subject to stormwater runoff quality standards.  |\n|  The proposed redevelopment will replace the buildings and sidewalk with a 2.5-acre warehouse, replace the existing 2-acre parking area with a 1.5-acre parking area and the wooded and grass area will remain at 1 acre. | The project will result in reconstruction of 1.5 acres of motor vehicle surface. As a result, the 1.5-acre motor vehicle surface is subject to stormwater runoff quality standards.  |\n|  The proposed redevelopment will replace the buildings and sidewalk with a 1-acre warehouse, replace the existing 2-acre parking area with a 2.5-acre parking area and increase the wooded and grass area from 1 acre to 1.5 acres. | The project will result in an increase of 0.5 acres of regulated motor vehicle surface and a reconstruction of 2 acres of motor vehicle surface. As a result, 2.5 acres of motor vehicle surface are subject to stormwater runoff quality standards.  |\n|  The proposed redevelopment will replace the buildings and sidewalk with a 2-acre warehouse, resurface the top asphalt of the existing 2-acre parking area and the wooded and grass area will remain at 1 acre. | Resurfacing the existing 2-acre parking area is not considered reconstruction of motor vehicle surface. Therefore, the 2-acre parking area is not subject to stormwater runoff quality standards.  |\n\n\n\"Regulated motor vehicle surface\" means any of the following, alone or in combination:\n\n1. A net increase in motor vehicle surface; and/or\n2. The total area of motor vehicle surface that is currently receiving stormwater runoff quality treatment either by vegetation or soil, by an existing stormwater management measure or by\n\n[Source PDF](SOURCE.pdf#page=3)"}
{"metadata": {"source_document": "NJ BMP", "version_year": "2026", "chapter_subchapter": "Chapter 4", "citation": "BMP 2026, Ch 4, p. 11", "topic": "Table 4-3: Typical TSS, Phosphorous and Nitrogen Removal Rates for BMPs"}, "programmatic_checks": {}, "content_markdown": "# Stormwater Pollutant Removal Criteria\n\n## Table 4-3: Typical TSS, Phosphorous and Nitrogen Removal Rates for BMPs\n\n|  Best Management Practice (BMP) | Total Suspended Solid Removal Rate (%) | Total Phosphorus Removal Rate (%) | Total Nitrogen Removal Rate (%)  |\n| --- | --- | --- | --- |\n|  Cistern | 0 | 0 | 0  |\n|  Dry Well | 0 | 0 | 0  |\n|  Grass Swale | 50 or less | 0 | 0  |\n|  Green Roof | 0 | 0 | 0  |\n|  Manufactured Treatment Devices | 50 or 80 | Not Rated | Not Rated  |\n|  Pervious Paving System | 80 | 60 | 30  |\n|  Small-Scale Bioretention Basin/Bioretention Basin* | 80 or 90 | 70 | 30  |\n|  Small-Scale Infiltration Basin/Infiltration Basin* | 80 | 60 | 30  |\n|  Small-Scale Sand Filter/Sand Filter* | 80 | 50 | 30  |\n|  Vegetative Filter Strip | 60-80 | 15 | 0  |\n|  Standard Constructed Wetland* | 90 | 50 | 30  |\n|  Extended Detention Basin* | 40-60 | 20 | 20  |\n|  Subsurface Gravel Wetland* | 90 | 50 | 30  |\n|  GI Wet Pond * | 50-90 | 50 | 30  |\n\nSource context and notes:\n\n# Stormwater Pollutant Removal Criteria\n\nSource revision: January 2026.\n\nvarious forms of nitrogen must also be considered in this selection process. The chosen BMP must meet the TSS criteria and also must maximize nutrient removal from stormwater runoff from the site. To assist with the selection of BMPs for nutrient removal, information regarding typical nutrient removal rates is provided in Table 4-3 on the following page.\n\nTable 4-3: Typical TSS, Phosphorous and Nitrogen Removal Rates for BMPs\n\n\n|  Best Management Practice (BMP) | Total Suspended Solid Removal Rate (%) | Total Phosphorus Removal Rate (%) | Total Nitrogen Removal Rate (%)  |\n| --- | --- | --- | --- |\n|  Cistern | 0 | 0 | 0  |\n|  Dry Well | 0 | 0 | 0  |\n|  Grass Swale | 50 or less | 0 | 0  |\n|  Green Roof | 0 | 0 | 0  |\n|  Manufactured Treatment Devices | 50 or 80 | Not Rated | Not Rated  |\n|  Pervious Paving System | 80 | 60 | 30  |\n|  Small-Scale Bioretention Basin/Bioretention Basin* | 80 or 90 | 70 | 30  |\n|  Small-Scale Infiltration Basin/Infiltration Basin* | 80 | 60 | 30  |\n|  Small-Scale Sand Filter/Sand Filter* | 80 | 50 | 30  |\n|  Vegetative Filter Strip | 60-80 | 15 | 0  |\n|  Standard Constructed Wetland* | 90 | 50 | 30  |\n|  Extended Detention Basin* | 40-60 | 20 | 20  |\n|  Subsurface Gravel Wetland* | 90 | 50 | 30  |\n|  GI Wet Pond * | 50-90 | 50 | 30  |\n\n\nNote\n* The BMP can be used to meet the stormwater water quality standards only when a waiver or variance from N.J.A.C. 7:8-5.3 is obtained.\n\nThe nutrient removal rates presented in Table 4-3 should be considered typical values based upon data from a range of research studies. Due to the multiple forms and complex behavior of nutrients in stormwater runoff and the similarly complex processes by which nutrient loading is altered by BMPs, actual removal rates for specific BMPs and development sites may vary.\n\nThe nutrient removal data in Table 4-3 is intended to assist designers in the selection of appropriate BMPs to meet the maximum feasible nutrient removal requirement in the Stormwater Management rules. During this selection process, primary consideration should be given to achieving the TSS removal\n\n[Source PDF](SOURCE.pdf#page=11)"}