New agricultural cost-share policies and nutrient control practices are needed if the region is to achieve and maintain the nitrogen and phosphorus reductions required to clean up the Bay, says a new paper from a scientific panel.

The paper, noting that past agricultural nutrient reduction efforts were less effective than originally anticipated, called for stepped-up research and sharp policy shifts to help curb farm runoff, which is the largest single source of phosphorus and nitrogen to the Chesapeake.

The paper suggests major changes in current agricultural production systems—from the diets fed to farm animals to the types of crops grown on fields—to help balance the flow of nutrients in and out of individual farms and watersheds. More research is needed to find ways to achieve such a balance while keeping farms profitable, the paper said.

It also called for changing government cost-share programs to encourage performance-based programs, and said programs should be targeted to problem watersheds.

The paper stems from a two-day forum convened last May by the Bay Program’s Scientific and Technical Advisory Committee which brought together leading experts on various aspects of agricultural nutrient pollution control from the region to identify key policy and research issues.

The paper—which offers nearly 100 research and policy recommendations—summarizes their conclusions, and sets the stage for a follow-up workshop that will lay out a more detailed short– and long-term research strategy.

Traditionally, agricultural nutrient control efforts in the Bay watershed have emphasized voluntary programs which use various cost-share programs to encourage farmers to implement “best management practices” such as developing nutrient management plans, planting stream buffers, building manure storage pits or other actions intended to reduce runoff.

That approach has failed to achieve anticipated nutrient reductions in the past. In part, that’s because of shortcomings in the computer models used by the Bay Program to estimate nutrient reductions, and because the effectiveness of many BMPs have been overestimated.

The Bay Program last fall adjusted its assumptions about many BMP efficiencies, which reduced the amount of nutrient control progress that had been previously estimated. Further improvements are expected over the next two years as the Bay Program updates the model, which should correct some problems.

“It’s not just the model’s fault,” said Tom Simpson, of the University of Maryland’s College of Agriculture and Natural Resources who helped to organized the forum. “Our BMP efficiencies are largely from plot-based research, and we know it is difficult to apply that to a watershed scale.”

Still, the paper said more research is needed to better evaluate real-world nutrient reductions from various BMPs, and suggests that further revisions about their effectiveness will be needed in the future.

Even then, the paper stresses, the present focus on implementing BMPs will not achieve the region’s water quality goals. It calls traditional BMPs “tactical” devices to improve water quality which cannot address the large-scale “strategic” nutrient problems facing many of the region’s agricultural areas.

Many existing BMPs respond to obvious problems, such as changing tilling practices to control erosion or building a storage shed to protect animal waste stockpiles from storms. But those tactics cannot compensate for large nutrient imbalances—both at individual farms, and for entire regions—as more nutrients are imported in the form of fertilizer and feed than are exported in crops or animal products. “As regional animal and nutrient stocks increase, risks to regional water quality increase correspondingly,” the paper states.

To help achieve a nutrient balance, the paper calls for more research on fundamental parts of the farm production system. New and ongoing research on animal diets, for instance, may help to reduce the amount of nutrients in manure.

Changes in crop rotations also hold potential benefits. Right now, crop production is dominated by a corn-wheat-soybean production cycle, which can harm water quality, but is encouraged by current government crop subsidy programs.

The paper said changes in the production cycle, including alternative crops such as warm season grasses which have less nutrient runoff potential, need to be explored, and new incentive programs developed to encourage the production of crops with less harmful impacts on the environment. But it said more research is required to determine what crop rotations could meet both the financial needs of farmers and water quality goals.

Further, Simpson said support is needed for demonstration programs to help show whether ideas that looked promising in research can be transferred to large-scale agriculture. “We need enough research to demonstrate that is is not going to create a major economic problem,” he said.

The paper also calls for sharp changes in the way government conservation programs are administered. Existing programs provide cost-share funding to farmers who implement various BMPs, but the programs are voluntary and the practices that are implemented are generally up to the farmer.

Instead, the paper said cost-share programs should be prioritized to emphasize watersheds with impaired water quality, and funding should be steered to practices shown to have the greatest nutrient reduction value. It calls for adding performance-based incentives that would pay farmers to undertake more aggressive nutrient reduction efforts, possibly combined with stepped-up water quality monitoring.

Under such a system, Simpson said, farmers would get additional payments for taking extra actions, but those actions would have to be measurable in some way. “It means you agree to some guaranteed level of performance that is beyond the regular expectation,” Simpson said. “You structure your incentives so that people want to move to a higher level of management intensity.”

The paper also recommended that farms actively participating in nutrient balancing and water quality monitoring should be prioritized for research support and technical assistance, and should receive more flexibility in designing nutrient control programs.

The white paper, “Innovation in Agricultural Conservation for the Chesapeake Bay: Evaluating Progress & Addressing Future Challenges” is available on the internet at