Crediting methods summary Crediting methods summary

Crediting methods summary. To access documents for each method, see the reference list at this link.
Link to this table

Location	Crediting method	Pollutants
Chesapeake Bay Watershed (entities subject to Bay TMDL requirements)	Reduction efficiency % reduction from existing load Qualifying lane miles -lb/acre reduction Mass load reduction	TN, TP, TSS
Florida	Mass load reduction	TN, TP
EPA Region 1 (New Hampshire and Massachusetts MS4 permittees)	Mass load reduction with efficiency factors	TN (NH only), TP
Massachusetts – stormwater requirements (not linked to MS4 permit)	Reduction efficiency - %	TSS
Wisconsin	Reduction efficiency progress towards % reduction target Reduction efficiency - %	TSS, with conversion to TP TP
Washington Ecology – MS4 permittees with TMDL	Mass load reduction, effective developed acres reduction	TP, sediment
County and City of San Diego and MS4 Co-permittees	Performance-based compliance	Cu, Zn, Pb, TKN, TP
Orange County and MS4 Co-permittees	Reduction efficiency - %	Bacteria, sediment
City of Santa Cruz, California	Modeled load reduction	Sediment
Vermont (Under development)	Interim – modeled load reduction Permanent – under development	TP
North Carolina (Under development)	Mass load reduction	TN, TP