Page 453 - Fair, Geyer, and Okun's Water and wastewater engineering : water supply and wastewater removal

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Typical Pollutant Removals 1 Groundwater Desired Soil Drainage Relative Land Elevation Conditions Area 2 Requirements Metals Pathogens Phosphorus Below Permeable Medium- Large Low- Low Low- facility large medium medium Near Impermeable Medium- Large Medium- Low Medium surface large high Near Impermeable Large Large Medium- Low Low- surface high medium Below Permeable Small- Large Medium- High Medium- facility medium high high Below Permeable Small Small Medium- High Low- facility high medium Below Perm

Structural BMP Initial Screening Criteria

Nitrogen Low- medium Medium Low Medium- high Medium- high High Low- medium Medium- high Low Low- medium Low 65–100%. 10–40 acres; large 40 acres.

Suspended Solids Medium Medium- high Medium- high Medium- high Medium- high High Medium Medium- high Medium- high High Low- medium 30–65%; high 0.4046 ha.

Table 12.5 Structural BMPs Detention Facilities Extended detention dry ponds Wet ponds Constructed wetlands Infiltration Facilities Infiltration basins Infiltration trenches/dry wells Porous pavement Vegetative Practices Grassed swales Filter strips Filtration Practices Filtration basins Sand filters Other Water quality inlets 1 Low 30%; medium 2 Small 10 acres; medium Conversion factor: 1 acre

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