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Event mean concentrations for total phosphorus.
Link to this table

Land cover/land use Range (mg/L) Recommended value (mg/L) Notes
Commercial 42-164 75 If applicable to models being used, adjust curve numbers/runoff coefficients when calculating loads
Industrial 70-170 93
  • If applicable to models being used, adjust curve numbers/runoff coefficients when calculating loads
Residential 42-101 73
High-density/Multi-family residential Calculate1
  • Insufficient information to recommend a specific emc
Medium density residential Calculate1
  • Insufficient information to recommend a specific emc
Low density residential Calculate1
  • Insufficient information to recommend a specific emc
Freeways/transportation 50-90 87
Mixed 47-188 76 or calculate
  • 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
Open space 11-70 21
Conventional roof <10
Institutional See note
Forest/shrub/grassland
Open water and wetlands see Notes (next column)
  • If data exist, use the TSS concentration for the water body of interest
  • If data for a specific lake do not exist, use data from similar lakes in the area
Cropland (row crops)
Pasture