December 11, 2001

The National Costs of the Total Maximum Daily Load Program

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The National Costs of the Total Maximum Daily Load Program (Draft Report) 

Stated Purpose:

"Congress directed the EPA to study the costs of implementing the Total Maximum Daily Load or ‘TMDL’ program."

Summary of RSP Comment:

The Draft Report attempts to estimate costs for the TMDL rule, but the rule is both prescriptive and open-ended, leaving states with little flexibility and substantial responsibility. The lack of knowledge about the extent of water quality problems and the very local nature of water quality issues has caused states to object to the broad federal authority asserted in the TMDL rule. The difficulties EPA has had in estimating the costs of the TMDL rule highlight this essential problem. While EPA has compiled detailed estimates of the costs of developing and implementing TMDLs, these estimates are not reliable measures of what the real costs of the program will be.

EPA should be commended for the detailed and technically sophisticated estimation of the costs of the "Least Flexible" implementation scenario. However, the data used to adjust these costs to form the "Moderately Cost-Effective" and "More Cost-Effective" scenarios is inadequate. EPA employs a sample of only 15 TMDLs to draw conclusions about costs in a population of 36,225 TMDLs. Given the variance in per unit TMDL types and costs, this sample is not statistically significant and any results arrived at through its employment are unreliable.

EPA also fails to include estimates for some important costs. The report did not consider some important pollutants and pollutant sources in determining the costs to implement TMDLs. More importantly, no attempt was made to estimate the costs of TMDLs that states will need to develop and implement based on future listings of impaired waters. EPA estimates that states will develop and implement 9000 future TMDLs, nearly 25 percent of the total number currently required, yet it included no implementation costs for these. Using a relatively straightforward approach to estimate some of the missing costs, we conclude that the costs of the "Least Flexible" scenario will be $2.45 billion to $5.26 billion per year.