Prescriptive TMDL Approach

•  Additional analysis to identify sources of pollution and estimate loading

•  Load allocations given to each DMA/ land owners

•  Assure that Ag WQ Management Area Plans or Rules and Forest Practices Act BMPs meet load allocations

A more prescriptive TMDL would evaluate loadings at the landowner scale and assigns load allocations to specific sources such as:

•  Land owners,

•  Crop type,

•  Land use.

TMDLs and Water Quality Management Plans (WQMP) would be developed to:

•  Identify loading capacity to meet a WQS (for example, DDT);

•  Use a surrogate for the load allocation (for example, suspended sediment) to meet the WQS;

•  Assign load allocations to specific public and private sources identified in the TMDL;

•  Identify “safe harbor” BMPs that could be used to meet the load allocation (for example, vegetation targets within a riparian management area);

•  Require TMDL Implementation Plans from all sources assigned a load allocation, sources would be required to identify in their plan how they will meet their load allocation;

•  The TMDL would be issued as an administrative order by DEQ.