When Capt. John Smith arrived in Virginia nearly 400 years ago, he was awed by the abundance of its waters. He wrote of once seeing enough striped bass near Jamestown to fill a 100-ton ship. Another time he reported seeing “more sturgeon than could be drowned by dog or men.”

Today, the rivers in Virginia appear far different. They are cloudy with sediment, while in some areas the oxygen level is often too low to support most aquatic species. Grasses occupy only a fraction of their historic habitat. And in some places, there are concerns about the potential for outbreaks of fish-killing pfiesteria.

What will they look like in the future?

Most likely, something between those images. Exactly what will be sorted out in the next few months.

The lower Virginia tributaries — those south of the Potomac and those on the Eastern Shore — are the first in the Bay watershed to undergo an evaluation where nutrient reduction goals will be based on what “living resources” need.

Ultimately, other Bay tributaries will be doing the same thing. Last year, the Chesapeake Executive Council — the governors of the Bay states, the EPA administrator, the District of Columbia mayor and the chairman of the Chesapeake Bay Commission — said that by its 1999 meeting, the Bay Program must determine whether nutrient reduction goals set in other rivers will provide water quality adequate “to support the living resources of the Bay and its tributaries.” If not, new reduction goals are to be set by 2001.

The James, Rappahannock and York are leading the way because, unlike other rivers from the Potomac north which had a 40 percent reduction goal, they never had a final nutrient goal.

That’s because the 40 percent goal was set to clean up the Bay. The lower tributaries, located closer to the mouth of the Chesapeake, have little impact on the Bay’s overall water quality. Yet they do contain large amounts of habitat — and potential habitat — for fish, crabs and other species.

So in 1992, when other rivers were assigned specific nutrient reduction goals, the lower tributaries were given only “interim” targets until “final” goals could be set to benefit habitats within each waterway.

Now, that time has come.

By living resources, though, officials are not talking — at this point — about John Smith’s striped bass and sturgeon. Instead, they are talking about underwater grasses and bottom-dwelling benthic organisms — worms and clams and so forth.

That’s because no one knows what, for example, a 50-pound reduction in nitrogen and a 10-pound reduction in phosphorus at a farm means for fish. But computer models can help predict what that would mean for grasses, because nutrients fuel algae blooms, which block critical sunlight for underwater plants. The grasses, in turn, are important habitat for juvenile blue crabs and many types of fish. More grasses, presumably, would ultimately mean more crabs and fish.

The same is true for benthics. When nutrients create more algae than can be consumed, the excess falls to the bottom and is decomposed by bacteria in a process that depletes the water of oxygen. Oxygen is critical for most aquatic creatures, and those that can swim or crawl will move away from oxygen-poor areas, though the remaining habitat may be greatly reduced, adding stress to the creatures. Predators and prey, for example, may be squeezed together.

Benthics, though, can’t move when things get bad. So healthy benthic populations — communities with large numbers of many species — are an indicator of good, sustained, water quality that also benefits other creatures.

This summer, Virginia released initial nutrient reduction strategies for the York, Rappahannock and James rivers. The strategies indicate that each river has areas with decent water quality, but that each also has poor conditions in large areas that prevent the establishment of healthy grass and benthic communities.

The strategies review water quality trends, where nutrients come from, nutrient reductions achieved so far, and the potential for future reductions.

The Bay Program has been busy developing and running elaborate computer models that will try to predict what magnitude of nitrogen, phosphorus and sediment reductions it will take to bring back grasses and make benthics happy.

Results are still coming in, but officials say it is unlikely the models will give a definitive answer to the key question: How much nutrient reduction — and perhaps sediment reduction — is enough? In all likelihood, it will be a matter that the more nutrient reductions, the better the water quality.

Of course, that also means more expense.

“The answer has to be something that is doable as opposed to fantasy,” said Rich Batiuk, associate director for science with EPA’s Bay Program Office.

“It’s all going to come down to some judgment,” said Alan Pollock, director of the Virginia Department of Environmental Quality’s Chesapeake Bay Office. “We know there are going to be a lot of different viewpoints on it.”

Indeed, there is concern over how much municipalities will have to spend on wastewater treatment plant upgrades, and farmers on runoff control to restore grasses or healthy benthics. On Virginia’s portion of the Potomac River, it has been estimated that state and local governments will spend about $450 million to meet their nutrient reduction goals.

The Hampton Roads Planning District Commission approved a “statement of principles” emphasizing that nutrient goals be based on “sound science” and take costs into account — particularly when it comes to setting any deadline.

At the same time, the Chesapeake Bay Foundation says the state is already dragging its feet in meeting interim nutrient reduction goals. “CBF sees little reason why Virginia should continue to delay developing plans based on agreed-upon interim goals when there is ample evidence the rivers and living resources would benefit now,” it said in a statement.

To set the goal, assessment teams for each river, which represent local governments, citizens and others, will review the modeling work. The teams are already starting to develop options — and costs — for different levels of nutrient reductions that may be sought.

In the Virginia tributaries, strategies may also have the extra element of needing sediment reduction goals. Monitoring shows the tributaries are more clouded with dirt than northern tributaries — in part because of soil differences — which blocks sunlight to grass beds.

Final strategies, with goals, are due Jan. 1. It’s unclear what the implementation deadline will be.

The computer models will help to show what type of nutrient and sediment reductions are needed to meet Bay Program objectives for dissolved oxygen, underwater grasses and other resources.

But officials caution that achieving those reductions — which may be greater than the present interim 40 percent goal — may not be technologically possible at present, or may be prohibitively expensive. In that case, the models will help to identify reductions that will improve key areas, if not achieve the total objective.

For example, grass beds could be restored in the upper James where they would improve local fisheries, and in the lower James where they would provide important shelter for juvenile crabs.

Poor oxygen conditions in the lower York and lower Rappahannock may be improved enough to expand habitat for fish and crabs to use previously uninhabitable areas and to restore grass beds.

“That gives us the beginning of what we are happy with,” Batiuk said. “We may not get all the way there.”

Pollock agreed it’s possible that the nutrient reduction goal set this year may not be a “final” goal, but the first step toward getting to clearer water, rather than trying to accomplish it all in one giant leap. That, he said, would allow scientists to assess progress — and the effectiveness of actions — as they go along. There’s more uncertainty involved in predicting results for giant reductions than for small ones, Pollock said, and presenting an overly ambitious, costly, plan could lose public support.

“We know the Bay is nutrient enriched,” Pollock said. “The thing to do is start reducing the input of nutrients. How far along we have to go to get the Bay and its rivers back to a more balanced situation is the question.”

Such an approach would, in effect, mirror the Bay Program, he said.

In 1987, the Bay Program started with the assumption that a 40 percent nutrient reduction would solve the Chesapeake’s water quality problem. By 1992, officials realized not only that the 40 percent reduction goal wouldn’t do what they thought — eliminate low oxygen conditions at the bottom of the Bay — but they would have difficulty achieving the itself.

Nonetheless, they saw that water quality would improve with nutrient reduction efforts, and proceeded to set goals that kept cleanup efforts moving ahead.

Pollock said the approach for the Virginia tributary strategies will probably take a similar approach — setting goals that keep the process moving.

It may not make all of the living resources happy in all of the places at all times, Batiuk and Pollock said. But more of them may have something to smile about than they do now.