A five year period of intensive research in the early eighties by the U. S. Environmental Protection Agency together with the states surrounding the Chesapeake Bay, determined that the health of the Chesapeake Bay was in jeopardy and that it was necessary to initiate a collaborative effort to restore this largest estuary of the country. It was further determined that while toxic pollutants were in fact causing detrimental impacts in certain localized areas of the Bay, the principle ubiquitous problem facing this estuary was dangerously low dissolved oxygen due to nutrient over enrichment. An overabundance of nutrients, or nitrogen and phosphorus, can adversely impact underwater living resources by causing algae blooms which decrease light penetration, and upon their decomposition, consume ambient quantities of essential dissolved oxygen. In a determined effort to address the problem, the U.S. Environmental Protection Agency (EPA), the Governors of Maryland, Virginia, Pennsylvania, the Mayor of the District of Columbia, and the Chair of a tri-state legislative body known as the Chesapeake Bay Commission signed the Chesapeake Bay Agreement in 1987, which among other things, stated that a 40% reduction of nutrients entering the Bay would be necessary to restore its health. This goal targeted a 40% reduction by the year 2000 of controllable nutrient loads from point and nonpoint sources in the entire 64,000 square mile Bay watershed from levels being discharged in 1985 , and that once achieved, this level would be maintained thereafter.