After a yearlong re-examination of regional nutrient reduction efforts, it is clear that progress has been made in reducing the amounts of phosphorus and nitrogen entering the Chesapeake-long the centerpiece of the Bay restoration effort.

At the same time, it appears the Bay states will fall short of their nitrogen reduction goal set for the year 2000. Just how short depends on the answer to a question: What is the goal? It can be interpreted two different ways.

Regardless of the answer to that question, many wonder whether either option will achieve the goal of the 1987 Bay Agreement, which is to "provide for the restoration and protection of the living resources, their habitats and ecological relationships."

"Ultimately, we need to reduce the input of the nutrients to optimize the health of the Bay," said Keith Gentzler, associate director for the Pennsylvania Department of Environmental Protection's Office for River Basin Cooperation.

"That's the bottom line," he said. "Who knows, with pfiesteria problems cropping up, what we thought was the right goal at one time may no longer be the right goal. We may have to be a lot more aggressive about reducing nutrients."

A clearer picture may emerge when the policy-making Chesapeake Executive Council meets Oct. 30 in the District of Columbia to review progress and set a course for the future.

The meeting will review efforts toward meeting the Bay Program's goal, set in 1987, of reducing the amount of nitrogen and phosphorus entering the Chesapeake 40 percent by the turn of the century.

The answer, in a nutshell, appears to be yes for phosphorus and no for nitrogen.

Exactly how much the nitrogen shortfall will be depends on what the goal is. And that is where the picture becomes murky.

The 40 percent reduction set in 1987 was based on a simple computer model that indicated such a reduction would eliminate "anoxic" conditions-the lack of oxygen-in the Bay. Excess nutrients trigger algae blooms which die, sink to the bottom and decompose in a process that depletes water of the oxygen critical to many species.

But many nutrients, which are essential to life, occur naturally, and cannot be controlled. So the 1987 goal became interpreted as a 40 percent reduction of controllable nutrients.

The amount of controllable nutrients was not determined until the goal was re-examined in 1991-92, with the aid of more sophisticated computer models. At that time, it was concluded that a substantial amount of nutrients were not "controllable," including those from portions of New York, West Virginia and Delaware within the drainage basin, as well as nutrients resulting from air pollution, septic systems and what is considered to be "natural" sources.

Using that controllable definition, a 40 percent reduction of the roughly 350 million pounds of nitrogen that enters the Bay in an average year worked out to 74 million pounds. Computer models showed that such a reduction would not end anoxic conditions in the Bay, but would still improve water quality.

The 74 million pound reduction was agreed upon and and used to set specific nutrient "caps"-limits not to be exceeded-for each major Bay tributary. Tributary strategies were then developed for those rivers to guide nutrient control efforts in a way that would achieve the overall Bay goal.

(The 40 percent reduction was only considered "interim" for rivers south of the Potomac, which in 1992 were thought to have less of an impact on the Bay. Final reduction goals for those rivers will be set over the next two years based on the needs of resources within those waterways. Nonetheless, the 74 million figure did include the "interim" reductions from lower Virginia rivers.)

Since 1992, the Watershed Model used to estimate the amount of nutrients entering the Bay-based of their movement through the landscape, down the rivers, and into the Chesapeake-was substantially refined. Using better information about land use, septic systems, the amount washing off forests and other variables, the model calculated that more than 15 million additional pounds of nitrogen were "controllable."

What, officials began to ask, did they agree t

  • A 40 percent reduction in the controllable load (equivalent to about a 90 million pound Baywide reduction for nitrogen)? or
  • Specific nutrient caps used as the basis for the tributary strategies (equivalent to a 74 million pound Baywide reduction in nitrogen)?

For now, the answer is the cap-which the tributary strategies were written to achieve-though it requires less reductions than the revised "controllable" figure would.

"We could argue for the next two years what the goal, and what the cap, should be," said Bill Matuszeski, director of the EPA's Bay Program Office. "The important thing is that we are moving very effectively in the right direction."

Using tributary caps set in 1992, the Bay will meet the phosphorus goal. But for the tributaries from the Potomac north, current efforts would result in a 9 million pound shortfall for nitrogen, which has proven to be the toughest nutrient to control.

Matuszeski said that control efforts already planned would probably achieve the cap goal by 2002 or 2003. But officials are continuing to explore options that could speed reductions to achieve the 2000 goal.

The bigger question is where to go from there, he and others acknowledge. Because of new modeling information, the "cap" is no longer 40 percent of anything, and sticking with the cap leaves the Bay cleanup effort open to criticism.

"I'd hate to see us get frozen into yesterday's thinking," said Mike Hirshfield, the Chesapeake Bay Foundation's vice president for resource protection, who knocked the Bay Program's failure to use the newer model information to reset its goals. "That is not a model of adaptive management, which is what the Bay Program has always prided itself on."

"We think that we've learned enough in the last few years to suggest that we can do more, and we think that we've also learned enough to say that the Bay needs more," Hirshfield said. "The modeled Bay may be doing fine, but the real Bay has pfiesteria and no SAV [submerged aquatic vegetation]."

Hirshfield said the initial 40 percent reduction should not be viewed as "the amount needed to save the Bay" but as an interim step in the cleanup. Nutrient reductions, he said, ultimately need to be based on the water quality needed by important resources, such as underwater grass beds that provide important food and habitat for waterfowl, crabs, juvenile fish and other species.

That is the approach that is planned for Virginia's tributaries south of the Potomac, which will soon embark on a process to set nutrient reduction goals based on the needs of resources in the rivers.

Many suggest that such an approach is needed for the rest of the Bay as well.

"Given the confusion over the goal, people are essentially saying that we want to move more toward a living resource response-based goal versus a strict numerical or percentage reduction-based goal," said Rich Batiuk, associate director for science with the EPA's Bay Program Office.

"We may need to take additional reductions to move us toward what we want, which is the restoration of the habitat."

Next year, work on an improved water quality model-to work in conjunction with the Watershed Model-will be completed. With it, officials say they can take a new look at how anticipated nutrient reductions will affect the Bay, as well as grass beds, bottom-dwelling benthic organisms and other resources.

"It may very well be that after we go through that, we will need to modify, refine, increase-and possibly in some areas decrease-our goals consistent with the responses we're getting," Matuszeski said.

But if further reductions are needed, that will raise more issues. Should the goal be revised now or later?

If the goal were changed now, Batiuk said, it could help begin planning future efforts. On the other hand, he said, those who have been striving toward the number set in 1992 could be left feeling as though someone moved the goal posts just as they neared the end-zone.

"It's something that we have to look at and handle delicately in some respects," agreed Alan Pollock, director of the Virginia Department of Environmental Quality's Chesapeake Bay Office. "We don't want the result to be that people feel they are getting the rug pulled out from under them after they committed to-and cooperated in-doing something."

For example, local governments have already committed millions of dollars for sewage treatment plant upgrades and other nutrient reduction efforts.

"These are major construction projects, and you don't do them and get a couple of years down the road and say, 'Oops, we did some modeling and really you've got to do more,'" Pollock said. "That doesn't go over too well, and that's pretty poor overall environmental management."

Pollock agreed that goals should be set on the needs of the Bay, but said the question is whether the goal needs to be reached in one big step, or a series of smaller steps over time. Nutrient levels are dropping, he noted, and will continue to drop for at least the next several years. "We think there are a lot of positive messages here," he said.