At six weeks of age, the average chicken produces about 5 ounces of waste each day. That may not seem like much, but multiply it by 80,000, which is how many birds may be found in a single commercial chicken house, and it's ankle-deep in short order.
For most farmers this has been regarded as a prized asset, not a problem. Poultry litter is periodically spread on fields to fertilize crops and spare farmers the expense of buying expensive commercial fertilizers. It's the proverbial cycle of life.
But the nutrients that are so helpful in growing plants can be deadly to the Chesapeake Bay and its tributaries. When found in excess, they promote the growth of algae blooms that absorb oxygen in the water as they decompose, literally suffocating aquatic life.
A recently-released study underscores this mounting problem. Farmland around the watershed is overloaded with phosphorus, according to the report produced by the Environmental Working Group, usually above and beyond what's needed to grow crops.
Animal waste is clearly the chief source. Within Maryland, the highest concentrations of phosphorus in the soil were found in the lower Eastern Shore, ground zero for the poultry industry — although dairy-rich southeast Pennsylvania and Virginia's Shenandoah Valley had high levels of the troublesome nutrient as well.
The obvious solution is to reconfigure what is known as the phosphorus "site index," the calculation that determines how much waste farmers should be allowed to spread on the fields without doing harm to the environment. That formula considers a number of factors, from the proximity of waterways to the composition of the soil.
Maryland has already pledged to reevaluate the formula, and other states have shown at least a modicum of interest in doing the same as part of their long-term regulatory plans recently submitted to the U.S. Environmental Protection Agency. That's good news. Local environmental groups say they are cautiously optimistic that tougher phosphorus standards will be revised to reflect this new understanding of the situation.
But the challenge lies in the economics of farming. What will farmers do with so many tons of manure if not spread it on their fields?
For about a decade, Perdue Farms has voluntarily been operating a recycling plant where poultry litter is dried, pelletized and sold as fertilizer — often outside the watershed. But there's little compensation to farmers aside from cleaning out their poultry houses for free. Elsewhere, animal waste is processed into fuel or composted into manure, but again, the profitability of these enterprises is suspect.
So the states are free to regulate (as they should), but they must do so with an understanding of the financial impact this could have on farmers. The profit margin for small dairy farms, for instance, is so slender that it might just drive them out of business. Turning farmland into shopping centers or townhouses could be even worse for water quality.
And while agriculture is regarded as the largest single source of phosphorus into the estuary, it isn't the only one. Run-off from streets and construction sites and wastewater treatment plants produces much of it as well. So farmers aren't the only ones that need to make changes.
Still, this is a problem that must be solved if Maryland and neighboring states are to be held accountable for the Chesapeake Bay and its degradation. The "greening" of Maryland agriculture might even be profitable if marketed correctly to consumers (although the global nature of the poultry market would pose a challenge). Agriculture may be an important economic asset to this state's economy, but so is the nation's largest estuary.