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) |
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 |
Calculate1 |
- Insufficient information to recommend a specific emc
- Concentrations vary widely depending on local conditions
|
| Medium density residential |
0.18 - 0.40 |
Calculate1 |
- Insufficient information to recommend a specific emc
- Concentrations vary widely depending on local conditions
|
| Low density residential |
0.24 - 0.40 |
Calculate1 |
- Insufficient information to recommend a specific emc
- Concentrations vary widely depending on local conditions
|
| Freeways/transportation |
0.25 - 0.45 |
0.280 |
- 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 |
0.290 |
- Residential land use was the primary land use in most studies that cited values for mixed land use
- If the study area can be delineated into specific land uses and impervious area for each land use is know, we recommend calculating the emc
|
| 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 |
0.190 |
|
| 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 - 0.45 |
0.090 |
Concentrations are likely to vary with season in areas with fall leaf drop |
| Open water and wetlands |
|
see Notes (next column) |
- 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.
|
| Cropland (row crops) |
0.126-1.348 |
2 |
Median from our review = 0.533 |
| Pasture |
0.35-0.45 |
2 |
|
1The link takes you to information on calculating event mean concentrations for areas with multiple land uses.
2Our literature review was not extensive enough to warrant a specific recommend emc for this land use
