The Chesapeake Bay is the largest estuary in North America, home to more than 3,600 species of plants, fish and animals. Nearly 16 million people live in the Bay watershed.The basin that drains into the Bay covers nearly 44.5 million acres over six states and the District of Columbia. The Chesapeake Bay has the highest land to water ratio of any estuary in the U.S. Land based activities heavily influence the condition of the Bay. Major environmental challenges in the Chesapeake Bay region include landscape change, excess nutrients, sediments, toxic chemical contaminants, and air pollution (Chesapeake Bay Program, 2006). Conversion of land from agricultural to other uses creates a complex interaction among resource concerns, including increased runoff. Urban and suburban areas deliver the highest pollutant loads on a per acre basis and occupy over 5 million acres of the watershed. Agriculture is identified as another top contributor of non-point source pollutants because it occupies such a large share of the non-forested portion of the watershed, approximately 10 million acres.