Information: This page was updated December 26, 2019. Read table caption below.
Event mean concentrations for total phosphorus. To see supporting information used to derive this table, link here.
Link to this table
| Land cover/land use |
Range (mg/L) |
Recommended value (mg/L)1 |
Notes |
| Commercial |
0.20 - 0.34 |
0.200 |
If applicable to models being used, adjust curve numbers/runoff coefficients when calculating loads |
| Industrial |
0.23 - 0.55 |
0.235 |
- If applicable to models being used, adjust curve numbers/runoff coefficients when calculating loads
- Adjust upward if specific phosphorus sources exist
|
| Residential |
0.26 - 0.38 |
0.325 |
Concentrations vary widely depending on local conditions |
| High-density/Multi-family residential |
0.28 - 0.40 |
Calculate |
- Insufficient information to recommend a specific emc
- Concentrations vary widely depending on local conditions
|
| Medium density residential |
0.18 - 0.40 |
Calculate |
*Insufficient information to recommend a specific emc
- Concentrations vary widely depending on local conditions
|
| Low density residential |
0.24 - 0.40 |
Calculate |
- Insufficient information to recommend a specific emc
- Concentrations vary widely depending on local conditions
|
| Freeways/transportation |
0.25 - 0.45 |
0.28 |
- Concentrations vary widely depending on inputs
- Adjust upward for areas receiving large inputs of road salt or sediment or having very heavy traffic loads
- Adjust downward for low traffic areas or areas with reduced inputs (e.g. little road salt application, limited truck traffic)
|
| Mixed |
0.16 - 0.84 |
0.29 |
Residential land use was the primary land use in most studies that cited values for mixed land use |
| Parks and recreation |
|
Use value for open space or calculate |
- emc will be a function of vegetative cover
- Adjust upward if street tree canopy cover is high or pervious areas are primarily grass on compacted soils
|
| Open space |
0.12 - 0.31 |
0.19 |
|
| Conventional roof |
0.01 - 0.20 |
0.030 |
|
| Institutional |
0.14 - 0.422 |
See note |
- Use low values in range (0.200 mg/L or less) for facilities such as campuses, where there is considerable pervious area
- Use high values in range (0.30 mg/L or greater) for areas with considerable impervious surface, such as sports facilities or facilities with large parking areas
|
| Forest/shrub/grassland |
0.03 - 0.25 |
0.07 |
Concentrations are likely to vary with season in areas with fall leaf drop |
| Open water and wetlands |
|
see note |
- If data exist, use the phosphorus concentration for the water body of interest
- If data for a specific lake do not exist, use data from similar lakes in the area
- emcs for wetlands will typically be higher than for lakes in an area. Consider using a value equal to 2 times the value for lakes in an area.
|
| Farmsteads |
|
|
|
| Cropland |
|
|
|
