The Bay Program’s approach to cleaning up the Chesapeake was implicitly endorsed in a recent National Research Council report on federal clean water programs.

The council, an arm of the National Academy of Sciences, issued a report in June that said the nation’s water quality programs should focus on the biological health of waterways rather than on setting effluent standards for dischargers, which has been the focus of the Clean Water Act for most of the last three decades.

Although the report never mentioned the Chesapeake Bay, it laid out a conceptual model similar to that undertaken by the Bay Program to set its cleanup goals.

“We were ahead of our time,” said Diana Esher, acting director of the EPA’s Bay Program Office. “It was good to see that academy report come out and support our conclusions.”

In their Chesapeake 2000 Agreement, the EPA and the Bay states agreed that the old water quality standards for the Chesapeake should be replaced with new ones that would “support the aquatic living resources of the Bay.”

A water quality standard consists of two parts, a designated use which describes the ultimate goal for a waterbody, and criteria that can be measured to determine whether the designated use is achieved.

Like most of the nation’s waterbodies, the Bay’s existing designated use is that it be “fishable and swimmable” — the Clean Water Act minimum. The main nutrient-related criteria for the Bay is that it have 5 milligrams of oxygen per liter of water.

Scientists say that some areas of the Chesapeake have naturally low oxygen levels and cannot meet that standard. At the same time, some areas, such as spawning habitats, need more oxygen.

The new water quality standards divide the Bay into a series of designated uses, such as spawning habitats, shallow water habitats for grasses, open water habitats for adult fish, and so on. New criteria will be applied to each designated use based on the needs of the species using those areas.

Instead of a one-size-fits-all dissolved oxygen criteria, three new criteria are being developed. New oxygen criteria are aimed at ensuring that adequate amounts of oxygen are available in the right place at the right time. In some places, that means oxygen levels will be higher than required today; in other places, it will be lower. Also, a new water clarity criteria will ensure that important underwater grasses get enough light to grow, while chlorophyll a criteria are aimed at regulating the amount and types of algae in the Bay.

Once the standards are set, the Bay Program will determine the amount of nutrient and sediment reductions needed to reach the criteria for each designated use. The Chesapeake would not be considered “cleaned up” until those water quality standards are attained.

That is essentially the direction that the scientific panel said the nation’s clean water programs should move.

The panel observed that the fishable and swimmable goals used for more waterways “are too broad to be operational as statements of designated uses.” Instead, the report said, designated uses should be more specific to the types of fish or biological community in a particular body of water. Further, it said new criteria should be established to ensure that the biological goals are for the waterbody are attained.

Historically, the report notes, states and the EPA have measured success based largely on the setting of effluent limits in permits for industries and other dischargers, and then measuring whether those limits are met. Such an approach was useful to start the clean water program when there was often not enough information available to set goals based on aquatic life needs, the report said.

But the report said the effluent limit approach has frequently failed to clean up waterways because it focused on individual facilities, rather than looking at the cumulative impact of all activities on a waterway, including pollution from runoff. As a result, many of the nation’s waterways remain polluted.

Instead, the report said “the data and science have progressed sufficiently over the past 35 years to support the nation’s return to ambient-based water quality management.” In such a program, the total amount of pollution must be reduced, and “success is achieved when the condition of a waterbody supports its designated use.”

For information about development of the Bay’s new designated uses and criteria, see “Bay Program unveils draft criteria for clean Bay,” (July-August 2001 Bay Journal). A reprint is available in PDF format on the Bay Journal web site, www.bayjournal.com