It would be nice to be able to agree with Roy Hoagland's rather rosy view of the benefits of a Chesapeake Bay TMDL in his commentary, "While TMDLs won't cure the Bay, they will improve its health." But I have a hard time seeing how the promise of this rather ephemeral down-the-road, pseudo-regulatory solution can do anything but delay the actions we should be taking now to save the Bay.

Whoever wrote this ungainly term "TMDL" into the Clean Water Act, where it sat ignored for years, was not a communications major. I could take the rest of this commentary trying to explain what is meant by a Total Maximum Daily Load and how it should be devised and applied. And I would probably need a couple more articles to deal with nuances, corrections and disagreements. Let's just say that a TMDL in theory is a pollution budget in which each river or stream segment is supposed to have identified all of its pollutants and their sources, and then reductions are supposed to be allocated among the sources so the standards for water quality are met.

But as a practical matter, the reach of a TMDL would be greatly limited. The only easy way to carry out a TMDL is through limits set in permits authorized by the Clean Water Act. These are issued by the states for individual discharges from point sources; in the case of the pollutants of concern to the Chesapeake, these are essentially sewage treatment plants.

The ability of TMDLs to affect other permits is questionable, including stormwater permits issued under the Clean Water Act to urban counties and municipalities. Yet stormwater is a prime source of sediment overload to rivers and the Bay.

Finally, much of the pollution to the Bay comes from sources with no permits, such as agriculture. While there is some language in the Act that says the EPA should have "reasonable assurance" that the TMDL will be carried out for those sources, there is no further authority to back that up.

As far as the point sources are concerned, it is not clear what benefit we get from waiting until the long process of developing a TMDL is complete. We already know the state of the art for nutrient removal at sewage treatment plants; we know those technologies are cost-effective and that the cost is spread among a large number of users; and we know from studies that have already been done that all the major treatment plants will need to install those technologies to meet Bay goals. So why don't we just do it?

When we turn to stormwater controls, the rationale for waiting for a TMDL is even less convincing. Even though we have the potential authority to use the regional stormwater permits in urban areas, until now the actual language in these permits has been hortatory and vague, with a lot of public education and other "soft" requirements. The obvious change is to tie the TMDL-defined needs to flow and peak flow pollution reduction requirements in those stormwater permits.

While this makes sense in theory, in the real world look at what has happened with the Anacostia River, an example that Hoagland touts. A TMDL for sediments has been completed by the District of Columbia and Maryland. It calls for an 85 percent reduction in loadings, and notes that nearly all of the sources are land-based, primarily massive runoff from paved areas of Montgomery and Prince Georges counties and extensive resultant streambank erosion.

As Hoagland points out, there has been a strong effort by citizens to tie these reductions to the new county stormwater permit required for Montgomery, as well as revisions to the existing Prince Georges permit. What he doesn't say is that despite continual pressure, we have been waiting for years to get those permits reissued with flow reduction goals and limits. The EPA and the state clearly hope we will go away. We won't.

If 26 citizen-based groups can't seem to get action even on the Anacostia, where the TMDL is tied directly to the need for stormwater controls and all of the upstream areas are under the stormwater permitting authority, how can anyone expect a TMDL to have much impact at all on stormwater sources throughout the region?

As sad as the future of TMDLs looks for stormwater, it is even less promising with respect to largely unregulated agricultural activities, which are the source of nearly half of the nutrient loadings and more than 60 percent of the sediment loadings to the Bay.

While there are murmurs in recent court cases about the need for the EPA to take seriously the requirement that TMDLs provide "reasonable assurance" that reductions allocated to those sources can be met, exactly what that means in terms of EPA and state authority is far from resolved.

And there is little doubt that Congress is not interested in amending the Clean Water Act to allow the EPA or the states to expand the regulation of farmers, which is currently limited to large livestock operations. So it is not clear to me just what we gain by going through the lengthy process of developing TMDLs in the vast areas of the watershed where agricultural activities are the primary source of the pollution.

What is clear to me is what we lose. It will take time-technocrats are saying years-to put together the data and analysis necessary to develop these TMDLs, and they will have to identify sources other than sewage treatment plants where the authority to follow through is vague at best.

But we already know what needs to be done to clean up the Bay, what are the most cost-effective actions and what they cost. And we know what is lacking is the political leadership to establish and expand the revenue sources, the assistance programs for farmers and the regulations needed to get the job done.

The bottom line: TMDLs in the Bay will do little more than provide cover for years of data massaging and political inaction on things we know we should do now. My friend Hoagland's message is that there may be some signs of hope mixed in with the process. I would urge more skepticism. My view is that anyone who says that TMDLs will play a major role in cleaning up the Chesapeake is either misleading the public or engaged in self-deception.