Failure to meet the Bay Program’s 2010 cleanup goal will likely trigger exactly what the goal was intended to avoid.

In 1999, a judge set a timetable that would require a regulatory cleanup plan, known as a Total Maximum Daily Load, for the Bay by May 2011 at the latest.

At the time, many state and federal officials feared that writing such a plan for the entire 64,000-square-mile Bay watershed would inspire a spate of lawsuits that could bog down efforts to clean up the Chesapeake.

So rather than immediately develop a TMDL, in June 2000 the governors of Maryland, Virginia and Pennsylvania; the EPA administrator; the mayor of the District of Columbia and the chairman of the Chesapeake Bay Commission, representing state legislatures, signed the Chesapeake 2000 agreement, which included a commitment to resolve the Bay’s water quality problems by 2010.

The rationale was that if the Bay was cleaned up before the deadline, a TMDL would not be needed.

A TMDL is a calculation of the maximum amount of pollution, or “load,” that a given waterbody can receive, while achieving its water quality standards, with a margin a safety. A TMDL also allocates those loads to various sources that contribute to the impairment of water quality.

It is also a regulatory tool. Once loads are allocated to sources, they become enforceable if the source is regulated under the Clean Water Act.

Officials say the full impact of a TMDL would likely be more muted today than if one had been developed in 1999 because the Bay cleanup has become more “TMDL-like” in recent years.

In 2003, the Bay Program created nutrient allocations for all major tributaries and states in the watershed that set the maximum amount of nitrogen, phosphorus and sediment they could release into the Chesapeake and still meet Bay water quality standards—similar to what would be required under a TMDL. States—including the headwater jurisdictions of New York, West Virginia and Delaware—then wrote tributary strategies that identified the actions needed to meet those allocations.

Based on those allocations, the EPA and all jurisdictions in the watershed last year agreed on a permit system for major wastewater dischargers. The new permits will establish specific nitrogen and phosphorus discharge load limits for each of the 453 affected wastewater treatment plants and industrial facilities.

“It is my opinion that, if a TMDL is done, most of the facilities will be permitted before it is in place,” said Bob Koroncai, a permitting official with EPA Region III. “And from that basis alone, a TMDL is not going to have its normal significant impact on implementation.”

Still, a TMDL would bring some changes. The new permit system targets the largest wastewater treatment plants and industries, which cumulatively contribute about 90–95 percent of the nutrients discharged in the watershed. A TMDL will probably go further, officials say. It would likely require that all dischargers, even small ones not affected by the current permit program, have permit limits. Exactly how strict those limits would be and how the permit process would be handled remains to be resolved.

It’s also possible that other types of facilities that need Clean Water Act permits, including urban stormwater systems and large animal feedlots, could be affected. Right now, such permits typically require the use of certain runoff control technologies or techniques—but they don’t set specific limits on pollution discharges. It’s unclear how, or whether, that would change. “Writing water quality-based permit requirements for urban stormwater discharges is in its infancy,” Koroncai said.

Major sources of pollution, such as runoff from agricultural and suburban lands, would remain unregulated.

“The TMDL only puts more certainty toward the regulatory aspects of implementation,” Koroncai said. “A lot of the implementation that needs to be done out there is nonregulatory agriculture. The TMDL gives us no additional authority to regulate farmers. You still have that piece out there that needs to be implemented, and the TMDL does not further that ball.”

But under a TMDL, states would have to provide more detail about how they would achieve reductions from unregulated sources. It would require “reasonable assurance” that those actions would be taken. That could mean demonstrating adequate incentive programs are in place to ensure that needed actions will be implemented.

In addition to those changes, the nutrient and sediment allocations made for each river would likely be revisited to meet the requirements for a TMDL. “The bar is set higher for TMDLs,” said Rich Batiuk, associate director for science with the EPA’s Bay Program Office.

For instance, a TMDL requires that allocations include a “margin of safety” to protect water quality against uncertainties such as weather extremes, which could flush greater amounts of nutrients into the Bay. Typically, TMDLs require an additional 10 percent pollution reduction to provide that margin of safety, although how that would be handled for the Bay remains to be determined.

Right now, allocations are made to individual state portions of each major tributary, and to fairly broad sources of nutrients, such as urban areas, agriculture and point sources. It’s likely that when a TMDL is developed, allocations will be made on smaller scales, and to more specific sources, but those details also remain to be determined, Batiuk said.

In another change, the TMDL would almost certainly account for nutrient contributions originating from air pollution, which may be the source of up to a third of the nitrogen entering the Bay. In current allocations, air pollution is considered indirectly, as part of the runoff from other land uses, such as urban or agricultural areas. Under a TMDL, air contributions to specific areas would be more clearly identified, though it is unclear how they would be dealt with.

Although the Chesapeake 2000 agreement goal likely will not prevent a TMDL, Batiuk said it bought time to establish a more defensible regulatory program. The water quality standards in place for the Bay in 1999 were not attainable, and permits written to achieve those standards would have been challenged in court, he said.

Instead, new water quality standards were developed for the Bay in consultation with all seven jurisdictions in the watershed. The new standards are based on decades of research about the water quality needs of fish, shellfish, underwater grasses and other Bay resources.

Development of the standards took years, so the allocations to tributaries were not made until 2003. But the standards, and the nutrient and sediment reductions needed to meet them, have been accepted by all jurisdictions in the watershed.

“Folks who are way upstream had an equal say at the table on the standards, the load allocations—and all aspects of decision making—as folks who have tidal waters along their land,” Batiuk said.

As a result, fears about lawsuits challenging permits based on the standards have not materialized, and permits for more than 50 of the 453 affected dischargers are already in the works. Nor has the worst case scenario of states suing other states developed.

“That alone is a humungous victory,” Batiuk said. “We had the time to get our partners to accept it, to understand it, to know that they had to do it.”

He noted that a permit is in the works for a facility in Binghamton, NY, which will require a multimillion dollar upgrade. Part of the upgrade is needed to achieve nitrogen reductions that will help attain water quality standards hundreds of miles away in the Chesapeake.

“The majority of the nitrogen reduction benefits will be felt about three or four days later when they reach the Bay, after passing through two other jurisdictions,” Batiuk said. “Nowhere else in the country have we seen multiple states—upstream states—agreeing to such significant restrictions to benefit downstream states’ water quality, with very little to no local benefits. It’s pretty incredible.”

Total Maximum Daily Loads

The Clean Water Act requires states to survey waterways every two years and report those that fail to meet water quality standards to the EPA. This is known variously as the 303(d) list, the impaired waters list, or the dirty waters list.

The act then requires states to develop cleanup plans, known as Total Maximum Daily Loads, for those waterways. That part of the law often was not enforced until a spate of lawsuits in the late 1980s and 1990s. One of those suits was against the EPA for failing to require TMDLs for Virginia waters on the impaired waters list, including the Bay. As part of the settlement for that case, a TMDL was required for the Bay by May 2011.

Key parts of a TMDL include the establishment of the maximum amount of pollution that a body of water may receive and still meet its standards, with a margin of error. That “load” is then “allocated” to sources contributing to the problem, essentially setting a pollution limit for each source. When that source has a permit, the allocation is typically required to be part of the permit.

A TMDL also requires “reasonable assurance” that those allocations will be met, including identifying adequate programs and funding to help ensure needed pollution reductions will be achieved for unregulated sources. Nonetheless, a TMDL does not necessarily set a time frame for achieving water quality standards, and does not guarantee implementation by nonregulated sources.