The commentary, "Bay is quietly dying as polluters pile on the manure," (September 2008) is long on opinion and short on facts regarding poultry manure and how it is used in Delaware, Maryland and Virginia to help farmers stay in business and provide the open spaces enjoyed by so many people free of charge.

With all due respect, the author does not know what he is talking about when he inaccurately singles out poultry manure as the major culprit in the Bay's problems. Because the commentary was absent of facts, in large part because it relied on newspaper stories, editorials and headlines, please allow us to provide some.

Unlike residential and commercial development sites that have no state laws governing how many nutrients they can apply to their land, poultry growers in our three states must manage and land apply nutrients in compliance with rigorous state laws that were enacted more than eight years ago. And the poultry industry has a long record of promoting and implementing conservation measures, such as the use of the phosphorus- reducing enzyme, phytase, in poultry feed and investments in alternative uses for poultry manure.

But the bigger issue is the relative contributions of the poultry industry to Chesapeake Bay water quality problems.

More and more people and agencies have recognized that increases in human population in the Chesapeake Bay watershed will make it extremely difficult if not impossible to meet the 2010 water quality goals. There is a general consensus that developed land contributes more pollution to the Bay and its tributaries than farmland and that there is more developed land and less farmland each year.

The Chesapeake Bay Foundation has stated that agriculture is "important to the region's environment, because well-managed farmland provides crucial water filtering" and that we "cannot restore the health of the Chesapeake Bay without ensuring a healthy agricultural economy in the region." Groups like the Foundation and the Center for Conservation Incentives at Environmental Defense seem to have recognized that demonizing the poultry industry is no way to ensure a healthy agricultural economy and stem the tidal wave of development that poses a far greater threat to water quality.

Farmland helps to filter water. Impervious surfaces don't. There has been a significant increase in impervious surfaces in recent years throughout the watershed. In the 1990s, impervious surfaces increased by 41 percent while the human population grew by just 8 percent. In those same years, the percentage increase of poultry houses in our states trailed the overall increase in impervious surfaces.

Chesapeake Bay Program data in the Sept. 10, 2007 report, "Development Growth Outpacing Progress in Watershed Efforts to Restore the Chesapeake Bay," show that agriculture trails human-caused contributions of nitrogen and phosphorus to the Bay. Human-caused contributions include the Bay Program categories of wastewater, septic, mixed open, and urban runoff. Those four categories are larger than agriculture for nitrogen (44 percent for the human- caused activities versus 40 percent for agriculture) and phosphorus (52 percent for human-caused activities versus 45 percent for agriculture). Keep in mind that poultry manure is just one sector of agricultural nutrients.

The Bay Program reports that "The human population in the Chesapeake Bay watershed is now growing by more than 170,000 residents annually. Restoration efforts center on reforesting streamside buffers, developing watershed management plans and preserving open space. Partners appear to be on track with many of their watershed protection efforts and are two-thirds of the way toward meeting current program goals, but these efforts appear to be inadequate in stemming the decline in water quality associated with population growth."

Since 1985, there has been a negative 90 percent in achieving the 2010 nitrogen goal in urban/suburban areas and a negative 67 percent for phosphorus. Agricultural-only data show success in reaching the 2010 Bay Program goals. Clearly, agriculture is moving in the right direction and the pandemic of development is causing most of the problems.

Quoting a U.S. Geological Survey report, "Increasing human populations and the associated land-use changes continue to be the primary factors causing water quality and habitat degradation in the Bay and its watershed."

Thanks to the poultry industry, thousands of other farmers in our regions are able to stay in business by providing the poultry industry with corn and soybeans, the primary ingredients in the poultry diets. Without the poultry industry, hundreds of thousands of acres of less-polluting land would likely be converted to higher-polluting developed land.

Regarding the statement in the September Bay Journal that "polluters pile on the manure,' readers must understand that poultry manure is a valued product on farms and is not considered a waste product. Recent University of Delaware data show that the nutrient value of a ton of poultry manure exceeds $100.

Surely, farmers are not going to be wasting this valuable resource by "piling it on." In fact, in many areas of our states, manure is a hard-to-find commodity because many farmers are switching to it from more expensive commercial fertilizers. They're not going to just pile it on their land to get rid of it.

Unlike 20 years ago, poultry manure today is commonly land-applied at less than 120 pounds of phosphorus per acre, less than 150 pounds of nitrogen per acre-and in accordance with conservation practices.

Changes made in agricultural practices, including state-regulated applications of manure to farmland and numerous voluntary best management practices, may not show results for years or decades. According to the U.S. Geological Survey, the age of groundwater in shallow aquifers in the Chesapeake Bay watershed ranges from less than one year to more than 50 years, with a median age of 10 years, so water moves slowly underground.

Agriculture is making progress in water stewardship, but it will take time for the improvements to show up in the Bay. Despite our efforts, the Bay will not ever recover without commensurate efforts to address pollution from population increases and development.

In fact, noted environmental author Tom Horton, in a new study titled "Growing! Growing! Gone! The Chesapeake Bay and the Myth of Endless Growth," writes: "So why do we persist in ignoring a widely acknowledged root cause of pollution like population growth, in light of our failure to clean up the Chesapeake Bay (and many other national environmental messes)?" He continues: "Human numbers and an economy built on their constant expansion is the missing link. Continuing to ignore growth renders most environmental progress in all other areas temporary."

We did not get where we are on Bay water quality issues overnight, and the improvements being made by the poultry industry will not appear overnight, but rest assured that the poultry industry in Delaware, Maryland and Virginia is working hard to minimize our contributions to water quality problems.