Every new person who enters the Bay watershed produces about 8 pounds of nitrogen and nearly 1 pound of phosphorus every year.

Every 1,000 additional chickens produces about 72 pounds of nitrogen and 32 pounds of phosphorus before they make it to the dinner table.

The millions of more people and chickens on the way — not to mention hogs, houses, parking lots and other nutrient sources — could add up to a big nutrient control headache in coming years.

To head that off, the Bay states are supposed to be able to hold the line on all additional nutrients associated with growth in people, animals and development when the clock strikes midnight on Dec. 31, 2000.

That’s because Jan. 1, 2001 begins what might be called, “the age of the cap.”

In 1992, the Chesapeake Executive Council agreed that when they achieved their nutrient reduction goals, they would “cap” the amount of nutrients entering the Bay at those reduced levels.

“Our commitment is to have no net increase in nutrient pollution in Chesapeake Bay from 2000 — forever,” said Tom Simpson, coordinator of Chesapeake Bay agricultural programs for the Maryland Department of Agriculture and the University of Maryland’s College of Agriculture and Natural Resources. “That’s a heck of a goal. If we can actually do that, it will be quite an accomplishment.”

Simpson chaired a Bay Program workgroup that has produced a report to guide the development of strategies by each Bay state — due by the end of next year — to successfully “cap” nutrient growth.

The watershed’s population is expected to grow from 15 million to about 18 million people by 2020, and continue upward. They will consume more food, require more developed land, more cars — actions that ultimately translate into more nutrients produced. The report says maintaining the cap in the face of such growth will be a daunting task that “will require changes in individual behavior.”

“Choices by homeowners, car owners and all consumers impact nutrient pollution,” the report said. “Ultimately, we we will need to measure quality of life by something other than the level of resource consumption.”

No matter how hard it is to maintain a cap, Bay jurisdictions in all likelihood will ultimately have to do more than just tread water in the nutrient arena. It’s expected they will have to reduce nutrients far more to restore healthy aquatic conditions in the Bay, then maintain that cap.

Until those new goals are set, Bill Matuszeski, director of the EPA’s Bay Program Office, said it was critical to hold the line on nutrient “loads” to the Bay to keep from losing ground in the cleanup effort. “The cap strategy is absolutely essential for the credibility of the program and the overall cleanup effort,” he said.

The implications of a cap are great. It means that every pound of nutrient growth from sewage treatment plant expansion, industry, agriculture, subdivision or any other source has to be eliminated through new technology, or offset by reductions somewhere else.

“I think people are struggling with the hope that there is something other than an offset out there, but I don’t think there is,” Matuszeski said. “The fact of the matter is that we are going to have to learn to love offsets.”

For the most part, the details of handling nutrient growth have not been dealt with. Strategies developed by the states to reduce nutrients never addressed ways to maintain those reductions.

The new report said that a credible cap strategy will require states to carefully track activities that add, or decrease, nutrient loads. The report suggests that “substantial” new nutrient sources be required to offset their increase.

That could happen through the use of new technologies, land use conversions — returning land to wetlands or forests — paying for reductions elsewhere, the establishment of nutrient trading programs or “banks” that buy and sell nutrient “credits,” or by other means. The Bay Program has already established a special workgroup to explore nutrient trading issues.

“I don’t see how you make this work without an offset program,” Simpson said. Exactly how offset programs work would be up to each jurisdiction. They could free up room for new activities and development under their cap by requiring further controls on existing activities. Or, they could require large new nutrient sources to pay for reductions elsewhere to offset the new nutrient sources.

“But that means when you’ve got new industries, sewage plant expansion, large-scale animal agriculture, you’re asking them to do one more thing,” Simpson said. “And that is certainly politically difficult.”

Other tough questions remain. While the cap applies to Bay Program members — Maryland, Pennsylvania, Virginia, the District of Columbia — it does not apply to portions of the watershed in West Virginia, Delaware and New York. Unless efforts are made to convince those areas to control nutrient growth — or the Bay states work to offset nutrients from their neighbors — the amount of nitrogen and phosphorus could increase despite the cap.

“Our recommendation for the future is that it has to be a total cap to be meaningful,” Simpson said. “Why spend all that energy and money to restore water quality if you aren’t going to maintain it once you get there?”

Efforts to get participation from those states will likely be aided by the new effort to develop a Total Maximum Daily Load for the Bay, which would require nutrient reductions from all sources.

There are several areas of expected nutrient growth within the Bay watershed. The report says “substantial growth” in the poultry industry is expected in all three Bay states, as well as Delaware and West Virginia, with the most rapid growth occurring in West Virginia and Pennsylvania. More hog farming is expected in Pennsylvania and New York, and potentially in Maryland and Virginia as well.

Runoff from suburban areas is expected to increase as development sprawls across the landscape and more acres are covered with lawns, roads and driveways. A growing population will add to the amount of sewage going to wastewater treatment plants; the number of people using septic systems — which offer less nutrient removal than treatment plants — is also expected to grow.

Not all the news is bad. The amount of nitrogen entering from air pollution is expected to gradually decline over the next decade because of recent regulations. But some of the regulations that would provide the most benefits have been challenged in court.

The report makes several recommendations about what an effective cap policy should contain besides offset programs.

It said new developments need to be designed to minimize runoff through techniques such as clustering homes or buildings together to minimize land disturbance and reduce that amount of roads and pavement needed. Jurisdictions should also emphasize preserving open space and improve the management of where new growth takes place.

Another critical issue, the report said, is making sure that devices used to meet the current nutrient reduction goal are properly maintained. Some devices used to control stormwater or runoff from farms, or to confine animal wastes, can deteriorate over time, eroding their nutrient control benefits. “All cap strategies should contain a plan for maintenance and/or replacement of practices and structures,” the report said.

More difficult is tracking increases from “nominal” nutrient sources, such as new homes on septic systems or a slight expansion of a dairy farm, which — added together throughout a basin — can create significant amount of nutrients. Though small, such activities are widespread and may account for the largest total increase in nutrient growth, the report said. Jurisdictions need to find ways to ensure those loads are accounted for and offset.

In the long term, maintaining any cap could become more difficult as offsets and options gradually become exhausted unless new technologies are developed. Whether the cap ultimately is maintained, the report suggested, will depend on how people balance protecting the Bay and its tributaries with traditional views of growth.

“This will force us to rethink how we grow or expand and will ultimately only be accomplished through corporate political will and individual behavior change,” the report said. “It forces us to question growth as a measure of prosperity and sustainability and it raises the long-term issue of limits to growth in all sectors. Yet, if we do not accept this challenge, all of the gains that have been made in restoring the Bay will disappear in the face of growth.”

Copies of the report, “Maintaining Progress in Restoring the Chesapeake Bay; Holding the Line on Nutrient Pollution After 2000,” are available from the Bay Program at 1-800-YOUR-Bay, or on the internet at


Nutrient Growth

In 1985, about 342 million pounds of nitrogen and 25 million pounds of phosphorus are estimated to have entered the Bay from all sources. The Bay states have committed to reduce the amount of nitrogen by about 71 million pounds and phosphorus by 7 million pounds, then “cap” their “loads” to the Bay.

Here are some examples of how nutrient growth can take place:

  • Each person flushes more than 8 pounds of nitrogen and nearly 1 pound of phosphorus down the toilet each year. The population is projected to grow from about 15 million in 1995 to about 18 million in 2020.

  • Every 1,000 additional chickens produces about 72 pounds of nitrogen and 32 pounds of phosphorus before it reaches the dinner table. A typical new poultry house contains 28,000 chickens, and raises 5.5 generations of chickens a year.

  • The average acre of developed land generates about 11.2 pounds of nitrogen runoff and 0.66 acres of phosphorus runoff a year. Developed land is increasing rapidly in the watershed; Maryland alone projects more than 350,000 acres of development in the next two decades.