Page 454 - Fair, Geyer, and Okun's Water and wastewater engineering : water supply and wastewater removal

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Groundwater Elevation Below facility Near surface Near surface Below facility Below facility Below facility Below facility Depends on type Below facility Depends on type N/A

Desired Soil Conditions Permeable Impermeable Impermeable Permeable Permeable Permeable Permeable Depends on type Permeable Depends on type N/A

Drainage Area 2 Medium- large Medium- large Large Small- medium Small Small- medium Small Small Medium- large Low medium Small

Relative Land Requirements Large Large Large Large Small N/A Small Varies Large Varies N/A

Metals Pathogens Low- medium Medium- high Medium- high Medium- high Medium- high High Low- medium Medium Medium- high Medium- high Low

Typical Pollutant Removals 1 Phosphorus Low Low- medium Low Medium Low Low- medium High Medium- high High Low- medium High Medium Low Low- medium Low Medium- high Low Medium- high Low Low Low Low Source: U.S. Environmental Protection Agency Stormwater Best Management Practice Design Guide—Volume 1—General Considerations (2004).

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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